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271 Cards in this Set
- Front
- Back
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cellular respiration
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chemical energy in "food" molecules is captured and stored as energy in ATP molecules
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There are three different primary pathways of cellular respiration that release energy from food molecules. What do all three start with?
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Glycolysis
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Anaerobic Pathways
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don't use oxygen. oxygen kills most anaerobic organisms
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Alcohol fermentation
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starts and end with glycolsis ocures in cytoplasm.
1. does not require oxygen 2. produces only 2 ATP molecules 3. produces CO2 and ethanol 4. fungi alled yeast use this pathway to fermet beer and bread |
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Lactate fermentation
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starts & ends with glycolysis. Occurs in cytoplasm
1. does not require oxygen 2. produces only 2 ATP molecules 3. produces lactate or lactic acid 4. bacertia called lactobacilius use this pathway to break down glucose in milk to make cheeses, yogurt & other dairy. |
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Aerobic Pathway
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using oxygen in cellular respiration
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basic chemical equation for Aerobic Respiration
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C6H12O6 --> 6Co2 + 6H2O + 36 ATP
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Mitochondria
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maternally inherited only. mutations may be in some cells but not in others
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Where do fats and proteins enter cellular respiration?
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At different stages, often after glycolysis
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How does cyanide kill you?
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blocks cytochrome oxidase. stops electron transfer chain
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Why does cancer cause people to lose weight?
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Cancer cells grow so fast they often lack sufficient oxygen. They are limited to glycolysis. Glycolysis is inefficient and cells don't get enough energy.
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Compare the light reactions of photosynthesis and the electron transport chain of Aerobic respiration.
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Similar: both involve a bacterial endosymbiont. many of the same molecules (ATP synthase, cytochrome) H+ gradient used to make ATP
Different: Hydrogen ions move in opposite directions. Different final electron acceptor |
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Cardiovascular (Circulatory) System
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system of tubes & pumps that circulate fluids throughout the body
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Blood
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-contains blood plasma & blood cells
-about 1-1.5 gallons; -blood never leaves the blood vessels -considered a body tissue |
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Interstitial fluid
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watery fluid around cells (tissue fluid) moves in and out of blood vessels (about 3 gallons)
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Where does interstitial fluid drain?
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into the lymphatic system (part of the immune system)
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what drives the movement of interstitial fluid in and out of blood vessels?
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pressure differences between the inside & outside of the blood vessel
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Hemolymph
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mixture of blood & interstitial fluid
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open circulatory system
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hemolymph not contained in vessels; they do have hearts
a. can't control flow b. works only for small animals c. body movements increase circlation |
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closed circulatory system
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blood never leaves vessels
a. blood travels faster in vessels b. control blood flow by controling vessel diameter c. allows higher metabolic rates & activity |
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Respiratory pigments
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proteins in blood cells that carry gases. Allow blood to carry lot more oxygen than simple diffusion alone.
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what is your respiratory pigment?
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Hemoglobin
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What is the most common blood disorder?
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Anemia; blood carries too little oxygen. Anemia is a roblem with blood quality not quantity.
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3 Important characteristics of blood vessels
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a. elastic walls
b. muscles to control the diameter c. valves to prevent backflow |
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Vasoconstriction
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vessel gets smaller, blood pressure goes up.
Causes: anti-histamines, amphetamines, cocain, psiilocybin, eye drops |
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Hemophilia
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too little fibrin protein produced; trouble forming blood clots (caused by genetics or liver problems)
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Vasodilation
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vessel gets bigger; blood pressure goes down
-causes: histamines, lactic acid, too much CO2, ethanol, THC, lack of noise, lack of light, hot temps |
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Coronary Artery
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supplies the heart w/ blood
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coronary bypass
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blood vessel taken from another part of the body to bypass clogged coronary artery
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atherosclerosis
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hardened flat deposits inside arteries
*chloesterol: HDL = Good LDL=Bad |
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Arteriosclerosis
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hardening of artery walls. lose elasticity
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thrombus
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blood clot inside a blood vessel
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embolism
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when a thrombus or plaque breaks free and travels to another part of the body
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Angioplasty
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procedures to deal with plaques
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laser angioplasty
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blast plaque with laser
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balloon angioplasty
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inflate small balloon to open vessel, take the balloon out
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stent
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insert small, hollow tube to hold vessel open; leave inside
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Aneurysm
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balloon-like bulge of a blood vessel; can burst
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Stroke
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disturbance in the blood supply to the brain; can be caused by thrombus, embolism, or ruptured aneurysm
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HypOtension
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chronic low blood pressure
caused by anything that reduces blood volume: accidents, injuries, diuretics, diet pills |
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HypERtension
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chronic high blood pressure
caused by heart attacks, strokes, & aneurysms caused by anything that increases blood volume, genetics, aging, lack of sleep, too much salt |
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Myocardial infarction
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heart attack; irreversible damage to lack of oxygen
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Myocardial Ischemia
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heart attack; reversible damage to heart if oxygen supply can be restored quickly
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ischemia
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a problem with blood quantity not quality
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How many muscles are in the human body?
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about 600
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Muscle is made form two kinds of filaments
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actin (thin filaments): a protein
myosin (thick filament): a motor protein |
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MUSCLE CONTRACTION
A nerve impulse is sent to a muscle and casues the release of___________. This causes _______ filaments to grab the ________ filaments. |
calcium ions; myosin; actin
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MUSCLE CONTRATION
___________ is used to bend the myosin filament heads inward. This pulls the actin filaments closer together and _________ the muscle. |
ATP energy; shortens
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MUSCLE CONTRACTION
More___________ is used to separate the Actin and Myosin filaments and the whole process repeats over and over again until the muscle is fully contracted. ___________ is then used to reabsorb the calcium, which prevents Actin and myosin from binding and allows the muscle to relax. |
ATP Energy; ATP Energy
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Rigor Mortis
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No ATP is available to pump calcium away so Actin and Myosin filaments remain stuck together and muscles become rigid and stiff. Occurs for a short time after death
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Muscle cramps
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imbalances in blood ions cause the involuntary release of calcium ions
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muscle burn
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accumulation of lactic acid after anaerobic respiration.
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what causes muscles fatigue?
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calcium channels become leaky, muscles have trouble contracting and relaxing
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Muscle fiber types
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differ in their concentration of Myosin
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Fast-twitch
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white fibers, explosive speed, no endurance. Few mitochondria. Rely on anaerobic respiration so lactic acid builds up
ex. cheetah & rabbit |
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slow-twitch
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red fiber, good endurance, slower speed. Many mitochondria. Rely on aerobic respiration so lasts a long time
ex. wolf |
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Phoshagen System
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Phosphate for ATP formation is stored in molecules of creatine phoshate. lasts for about 10 seconds, anaerobic (Sprinter)
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Glycolytic System
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use glycolysis & lactate fermentation. lasts for 1-2 mins, (Swimmer)
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Aerobic Respiration
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slowest way to make ATP but lasts the longest. up to several hours (marathon runner)
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Genetic Control of Musculature
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myostatin gene inhibits muscular development mutations in myostatin cause excessive muscle development
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Exercise Physiology
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exercise doesn't make more muscle. fibers get bigger and more resistant to fatigue
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endurance training
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increases number of mitochondria in muscles and the number of capillaries serving them
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strength training
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makes muscle fibers thicker and promotes the synthesis of enzymes used in glycolysis.
Creates bulging muscles that tire quickly |
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Muscles burn fuel in this order:
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sugars --> fats --> proteins
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Endurance training
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light weights, many repititions. Increases the number of mitochonddria and capillaries serving the muscle
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Skeleton
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rigid body support with muscles attached
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Hydrostatic skeleton
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fluid or air held under pressure in a closed body compartment
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Exoskeleton
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a hard skeleton on the outside of the body; made form the protein chitin
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endoskeleton
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a hard skeleton on the inside of the body
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What is cartilage made from?
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collagen (protein) fibers
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What are bones made from?
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collagen strengthened by calcium phosphate
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How many bones are in a human infant?
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about 300
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how many bones are in a human adult?
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about 200-210
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What happens to the other bones?
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many of our bones fuse together as we grow
ex. skull |
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Do men and women have different numbers of rib bones?
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No, most adults have 12 pairs
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Four Functions of Bones
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a. movement
b. protect internal organs c. store calcium & phosphorus d. produce red & white blood cells (in bone marrow) |
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Osteoclasts
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cells that secrete acids and constantly remove bone
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Osteoblasts
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cells that constantly rebuild bone
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Until about age 24
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you add bone mass; osteoblasts work faster than osteoclasts
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What causes osteoporosis?
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Osteoclasts work faster than osteoblasts
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What is the function of bone marrow?
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produces red & white blood cells and stores fat
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Tendons
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muscle to bone connection
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Ligaments
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bone to bone connection
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Osteoarthritis
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cartilage shock absorbers between the bones wear away.
Usually, the fingers, knees, hips, and back are the most affected. Bones rub together |
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Scoliosis
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Unnatural curvature of the spine, side to side or front to back, or rotation. Pain, uneven arms or breasts. Thought to be controlled by genetics.
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Rickets
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softening of bones due to vitamin D deficiency. most common childhood disease i many developing countries
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Spina Bifida
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incompletely formed spinal cord and vertebrae so spinal cord sticks out of back. One of the most common birth defects. May be caused by Trisomy 18. Incidence reduced 70% by taking folic acid (vitamin B9 in leaft vegetables)
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Respiration
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the exchange of gases between an organism and surrounding environment
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Ventilation
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Increasing the flow of water or air over the respiratory surfaces
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Four important points about the diffusion of gases
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a. gases must pass through liquids to get to cells
b. the greater the surface area for gas exchange, the more gas can diffuse c. diffusion depends on gas concentration & gas pressure d. oxygen diffuses about 8,000 times faster in air than in water |
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What tyep of water holds the most dissolved oxygen?
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cold, fresh
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What type of water holds the least dissolved oxygen?
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Warm, Salt
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How much oxygen does water hold compared to air? Why?
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Air holds 20 times as much dissolved oxygen as water.
O2 is non-polar, H2O is polar. They don't want to mix |
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What forces drive gas into water anyway?
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Pressure, we use hemoglobin to help us carry alot more
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Gills
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Outfoldings of the body surface that are suspended in the water for gas exchange. The surface area is often much greater than the surface area of the rest of the body.
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Insects: Spiracles
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portholes on the outside of an insect's body for gas exchange
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what do spiracles connect to?
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a tracheal system; a system of air tubes throught the insect's body
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Does the open circulatory system of insects transport oxygen and carbon dioxide?
Explain |
No. Because the tracheal system touches all cells in the body
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Amphibians: Positive pressure
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air ushed into lungs and then sucked out
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Metamorphosis
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many amphibians use gills asjuveniles (tadpoles or newts) adn then use lungs as adults
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Pulmocutaneous Respiration
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respiration through the skin
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Birds: Air Sacs
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Birds have lungs & air sac system; air sacs attached to lungs
Most efficient respiratory system |
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Functions of the air sac system in birds
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a. one-way air flow
b. prevents mixing of old and new air c. reduces weight |
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Mammals: Negative pressure
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air sucked in then pushed out
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What kind of ventilation do mammals have?
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Tidal ventilation; in & out like the tides
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How do mammals ventilate?
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With a diaphragm, dome shaped muscle below the lungs
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How does the diaphragm work?
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Diaphragm down-air into lungs
Diaphragm up-air out of lungs |
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What is the name of the windpipe?
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Trachea
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What is the voicebox called?
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Larynx
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What does the trachea branch into?
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Bronchi
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What do the bronchi branch into?
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Bronchioles
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What do the Bronchioles branch into?
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Alveoli
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How many alveoli does the average human have?
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about 300 million
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Where does gas exchange tke place?
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Alveoli
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Does your brain tell you to breathe?
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Yes (unlike your heartbeat)
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How do we know when to breathe more?
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When CO2 levels in our blood get too high
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Asthma
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Bronchioles have smooth muscle to control the flow of air. This condition involves the involuntary contraction of the muscles and constriction of the airway; often caued by allergies or sudden temperature changes
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Emphysema
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Irreversible degenerative disease. Loss of elasticity in the small airways (alveoli) the result is that the small airways collapse during exhalation
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COPD
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Chronic Obstructive Pulmonary Disease.
A combination of Emphysema and Chronic bronchitis (inflammation of bronchioles) Airways beocme narrowed making ti difficult to breathe |
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Apnea
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Ventilation to the lungs is stopped for short periods (Sometimes hundreds of times per night) Can be caused by brain's inability to regulate respiration, by obstruction, or by an overdoes of depressants that relax muscles
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SIDS
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Sudden Infant Death Syndrome. Brain has trouble reading CO2 levels properly and doesn't tell infant to breathe.
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Pneumonia
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An inflammation of the lungs that leads to an accumulation of fluid and impairs lung function. Can be caued by bacteria, protists, viruses, and fungi. One type is called Legionnaire's disease. Another bacterial infection causes Tuberculosis.
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SARS
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Severe Acute Respiratory Syndrome. Caused by coronavirus. Very contagious, but the mortality rate is only about 5% for healthy adults; much greater for the elderly, very young or those with a compromised immune system
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Nutrition
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the study of what foods & how uch to eat in order to stay alive and healthy
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One calorie
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Amoutn of energy needed to raise the temperature of 1 kilogram of water 1 degree celsius
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Malnourished
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wrong types of food or wrong proportions
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Undernourished
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not enough food/calories
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Basal Metabolic Rate
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the energy cost of living; determined by hormones, temp, gender, fasting
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Soluble fiber
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fermented in the large intestine by bacteria to produce short-chain fatty acids ex. pectin
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Why is soluble fiber good?
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Removes cholesterol from blood, stabilizes blood sugar, helps immune system
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Insoluble Fiber
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called roughage, attracts water
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What is bran?
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The hard outer layer of cereal grains
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Why is bran good?
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Promotes faster movement of material through intestines. May reduce the risk of colon cancer
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Proteins
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most people who starve to death die because they lack protein not energy
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What are essential amino acids?
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8 Amino acids your body can't make
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What is Kwashiorkor?
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Severe protein starvation
stomach muscles consumed & weakened retain water, appear bloated |
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Vitamins
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organic compounds needed in small amounts for normal growth and metabolism
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Fat-Soluble Vitamins
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A,D,E, K; stored in fat tissue; too much can make you sick; need fat in teh diet to absorb these
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water-soluble vitamins
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C & B vitamins
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Minerals
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Inorganic elements required for the body to function
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Approximately how many minerals do we need for an active, healthy body?
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80
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Leptin
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Produced by fat cells, when fat cells shrink, liptin production decreases and you feel hungry
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Cholecystokinin(CCK)
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made by small intestine when you eat. Tells your brian you are full
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Ghrelin
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stomach & hypothalamus gland make it when you lose weight. Prevents you from burining stored body fat
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Weight control
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Energy In = Energy Out
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Problems with dieting
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a. Initial weight loss is high due to the water loss, but quickly slows
b. Body responds by going into starvation mode, lowers metabolic rate to conserve energy c. Gherlin production stimulates appetite and makes you want to go out and get food |
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Problems with diet pills
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a. Interfere with normal hormonal balance
b. speeds up metabolism, more oxygen radicals c. many kinds dehydrate you, giving you headaches and sometimes kidney stones |
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Exercise
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good for your brain muscles, heart, lungs, immune system & others
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How many calories does the averge person need per day?
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1500-2500 calories per day
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How many calories does the average runner burn per mile?
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100 calories per mile
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How much does a cheeseburger cost?
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About 5 miles
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How much does a 6-pack of beer cost?
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about 8 miles
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Most exercise physiologists recommend exercising for how long? Why?
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At least 20 minutes; Because for th efirst 20 mins. you are burning sugars that are in your bloodstream and cells. you have to burn through them first before you start to burn fat.
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Foregut fermentation (includes cows, shee, buffalo)
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multi-chambered stomach is where bacteria help digest food; very efficient system
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Hindgut Fermentation
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fermentation chamber is the caecum (appendix) located aftter the stomach. not as efficient
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Coprophagy
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common among small hindgut fermenters. send their plant diet through the digestive system twice. They have an inefficient digestive system
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What is the deadliest infectious disease in the world?
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acute respiratory infections
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Of the eight deadliest infectious disease how many are caused by bacteria or viruses?
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7 out of 8
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Pathogen
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an infectious disease causing organism
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Infection
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a pathogen invades a cell or multi-celled organism
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Epidemic
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a disease spreads through part of a population
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Pandemic
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epidemic spreads thruogh many populations at the same time
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Why don't pathogens kill us all?
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a. we evolved with them. our immune system can kill most of them
b. they kill each other |
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Where do antibiotics come from?
Why? |
From bacteria & fungi; because they are competing for resources and benefit by killing each other
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Prudent parasites
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parasites shold not kill their hosts or else they can't be spread
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binary fission
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asexual; produces two identical cells; can be very fast
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conjugation
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direct exchange of DNA through conjugation tube or sex pili
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transformation
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uptake of DNA directly form the environment
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transduction
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transfer of DNA from one bacterium to another by a virus
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Endospores
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bacterial spore that can survive harsh conditions (heat radiation, drying)
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Rhizobium
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Symbiosis between bacteria and plant roots that helps plants get nitrogen out of the soil. Associated with legumes--alfalfa, clover, peas, beans etc.
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Viruses
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a. 1000-10,000 times smaller than bacteria
b. DNA or RNA in a protein coat c. cannot reproduce itself can only reproduce using a host cell |
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Viroids
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a. circles of RNA with no protein coat & no protein coding genes
b. pathogens of plants & crop species c. Resemble Introns (non-coding regions of eukaryotic DNA) |
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Prions
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a. misfolded protein that cause other proteins to misfold and accumulate in brain tissue
b. resistant to boiling, baking, radiation & disinfectants |
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Protists
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single-celled eukaryotes placed in their own kingdom
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What are dinoflagellates?
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single-celled protiosts; cause algal bonds
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What are algae?
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Colonial protists
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Golden Algae
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Diatoms. Give off as much oxygen every year as all land plants
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Brown Algae
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important structure in marine ecosystems
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Red Algae
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source of agar used in jellies and cosmetics & eatn as food
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What important role do fungi play in ecosystems?
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Decomposers in the ecosystem
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What is the main component of the fungal cell wall?
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Chitin
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What are hyphae?
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A Chain of connected cells
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what is a mycelium?
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an interwoven mat of hyphae that forms the body of the fungus
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What type of nutrition do fungi have?
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Absorptive nutrition. Fungal cells secrete powerful exoenzymes that digest food outside the body.
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Saprobic fungi
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consumer dead organisms; they are the decomposers
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Parasitic fungi
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feed on living organisms
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Haustoria
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specialized parasitic hypae that invade living cells and secrete digestive enzymes
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A mold
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rapidly growing asexually reproducing fungus
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Yeasts
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unicellular fungi that live in damp places and can reproduce by budding
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Lichen
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a symbiotic relationship between a fungus and a cyanobacterial cell or a green algae
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mycorrhizae
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a symbiontic relationship between plant roots and fungi that helps plants absorb nutrients from soil, particularly phosphorus
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leaf cutter ants
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fungi farmers
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Nervous system
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specialized cells sense environment & allows rapid, long-distance communication between cells
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central nervous system
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Brain & spinal cord
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peripheral nervous system
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all the nerves connected to the brain & spinal
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Neuron(Nerve Cell)
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cell specialized for conducting electrical charges
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Sensory neuron
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directly senses the environment. send signals to CNS
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Nociceptor
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send pain signlas to the brain. detect potential damage to the body
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motor neuron
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directly contact muscles & glands & make them work. Receive signals form CNS
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Amyotrophic lateral sclerosis
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a progressive, usually fatal, neurodegenerative disease caused by the degeneration of motor neurons
Lou Gherig's Disease |
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Mirror neuron
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a neuron that fires when an animal acts & when it sees another animal perform the same action (monkey see, monkey do)
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What is a reflex arc?
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involuntary response to an external stimulus. A direct connection between sensory & motor neuron without a connection to the brain
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Cell Body
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main part of a cell with nucleus & other cell organelles
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Dendrite
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bring information to the cell body
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Axon
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carry information away from cell body
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myelin sheath
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lipid-rich insulation around the axon
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what are the two primary functions of the Myeline sheath?
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insulatiion; make nerve impuls travel faster
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Synapse
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tiny spaces between different nerve cells, or between nerve and muscle or glad cells
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Membrane potential
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the resting difference in charge between the insdie and outside of a nerve cell
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At res the inside of a nerve cell is _____________ charge. Why?
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Negatively; DNA and most proteins have a negative charge
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At rest, the outside of the cell is ____________ charged. Why?
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Positively; there are alot of sodium ions outside the cell
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Action Potential
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Temporary reversal of charge between inside & outside of nerve cell
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Sodium (Na+) Channel
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A protein channel in nerve cell membrane that controls flow of sodium ions into cell
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Potassium (K+) channel
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a protein channel in nerve cell membrane that controls flow of potassium out of cell
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sodium-potassium (NA+/K+) Pump
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uses ATp energy to pump sodium ions back out of nerve cell & pump potassium ions back in.
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How does an Action Potential move along an axon? Step 1
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Sodium channel open, NA+ ions flow into cell. Reverses charge inside & ourside of cell
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How does an action potential move along an axon? Step 2
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Step 1 causes next sodium channel to open. NA+ flows into cell. Action potential moves along axon away from cell body
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How does an action potential move along an axon? Step 3
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Potassium (K+) chnnels open right after sodium channels Potassium flows out of cell & restores negative charge inside and positive charge outside
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How does an action potential move along an axon? Step 4
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Sodium-Potassium pump usues ATP energy to pump NA+ out of cell & K+ back in membrane potential is resotred
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How fast do nerve impules travel in vertebrates?
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Fastest are about 400 ft/sec or 272 mph
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Invertebrates lack the myelin sheath. How fast do their nerve impulses travel?
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6.6 ft/sec or 4.5 mph
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Neurotransmitters
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hormones secreted into the synapes between nerve cells or btween nerve & muscle cells (more than 50 different kinds)
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where are neurotransmitters stored?
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in small vesicles at the tips of axons
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what causes the release of neurotransmitters into the synaptic space?
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calcium ions (CA2+)flow into the nerve cell & cause the release of the neurotransmitter
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After neurotransmitters are used, what happens to them?
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They are either reabsorbed & re-used by nerve cells or are destroyed by enzymes
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Depression
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in humans, low levels of norepinephrine and/or serotonin have been linked to clincal depression
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Addiction (Cocaine)
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cocaine blocks re-absorption of dpamine; bodry produces enzymes to destroy extra dopamine. Need more cocaine to get the same "high" when not using, body keeps destroying dopamine & you can't feel good unless you use coke
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neurotoxins
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many block ion channels fom opening or closing
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alcohol
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at high doese, can block potassium channels opena nd make them leaky even at rest. This lowers the membrane potential and causes slower reactions, stumbling and slurred speech
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Neurons and reproduction
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some neurons release gaes
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In certain male mammals, neurons release _______________ into the erectile tissue of the penis. In response the muscles in the blood vessel walls of the erectile tissue _____________ and allow the erectile tissue to fill with blood producing and erection.
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nitric oxide gas; vasodilate
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The erection is maintained because the veins in the erectile tissue are _______________. The result is that blood can get into the penis easily, but has a hard time getting out. An erect penis holds ___________ as much blood as one that is not erect.
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Vasoconstricted; 10 times
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How does viagra work?
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blocks an enzyme that blocks nitric oxide & allows Nitric oxide to work
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Blood-Brain Barrier
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cellular structure prevents bacteria and large molecules from entering nerous tissue; viruses can get through. water oxygen and glucose go through
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Tight-Junctions
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the spaces between the endothelial cells that surround nervous tissue. The spaces are full of proteins that make the spaces smaller so large molecules and bacteria cannot get through
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brain infections
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very hard to treat because most antibodies are too large to cross BBB. BBB also prevents the delivery of drugs like antibiotics to nervous tissue
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Alzehemier's Disease
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disruption in BBB allows blood plasma containg Beta Amyloid molecules to enter brain where it sticks to tight junctions forming Amyloid plaques that disrupt brain function (memory first)
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Seizures
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rapid simultaneous firing of neurons in the brain
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Epilepsy
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-episodic abnormal electrical activity in the brain;
-1-5% of people in the U.S -linked to weakening of the BBB |
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Tonic-clonic seizure
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most serious. accompanied by violent convulsions. can cause brain damage if too long
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absence seizure
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"mild" seizure. short duraction. stare into space or move around aimlessly. not remember it
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Cerebrospinal Fluid (CSF)
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fluid made by brain acts as interstitial fluid for nerve & brain cells
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Functions of CSF
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a. mechanical protection for brain & neurons
b. transport molecules around nervous system |
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Where does the CSF drain?
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into the lymphatic system
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CSF Pressure
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varies due to coughing or internal compression of Jugular veins in neck. holding a sneeze can increase this pressure
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CSF Pressure (Too High)
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can be fatal. can prevent oxygen, glucose, water from moving into the brain
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CSF Pressure (Too Low)
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Headaches when standing. blurred vision, hearing loss
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Meningitis
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can be caused by bacteria, fungi, viruses or protists that produce an infection in the CSF. The infection leads to inflammation of the protective membranes around the brain and spinal cord (called meninges) This inflammation can disrupy BBB and make it more accessible to pathogens
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brainstem
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survival functions (breathing, heart rate,etc) being alert and wawak. conducts information to higher brain centers
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medulla
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controls heart and blood vessel activity, swallowing, vomitting, and digestion
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pons
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regulates breathing in the medulla
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Midbrain
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coordinates vision and hearing. Visual reflexes in mammals. Rest of vision is coordinated in the cerebrum in mammals
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Limbic system
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ring of structures around the brainstem that play a large part in producing and interpreting emotions (other's emotions)
Learning and memory processes build a history of sensing and motor actions that successfullly obtain warmth and food |
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cerebellum
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coordinates movement, muscles, balance, and the position of the body in space. Hand-eye coordination
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Diencephalon
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deep-seated "pure" emotions (thirst,hunger anger, sex-drive) and circadian rhythms. Disorders such as OCD, depression affect this part of the brain
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Sleep
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active area of research. slee may help consolidate learning and memory
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Dreams (oneirology)
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About 2 hours each night. Replay events that happened or thought about
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Cerebrum
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memory, abstract thought, sensory perception, thinking language
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Does the leftside of your brain control the right side of your body?
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yes
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left side
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speech, language, logic, right side of your body
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right side
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artistic ability, music, left side of the body
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Memory/learning
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made up of neural pathways that differ in length, intensity and which types and amounts of neurotransmitters are used
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Short-term memory
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Hippocampus part of brain (limbic system)
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Long-term memory
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Frontal Lobes (cerebrum)
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What happens to irrelevant memories?
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they are forgotten
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How does alcohol abues affect memory
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impairs ability to form new, long-term memories = extreme for is blackout
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how does marijuana abuse affect memory
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impairs brains ability for form short-term memories
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What factors can affect the transfer of information from short-term to long-term memory
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a. practice
b. positive or negative emotional state associated with memory c. if new data can be associated w/ something previously learned d. repeated testing; practice like you play |
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Why did people evolve to have dark skin?
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block out the sun and protect folate reserves
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Why did people evolve to have light skin?
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take in the sun and produce Vitamin D during winter months
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