Midterm Definitions Physiology

Front 1

Action potential

Back 1

A large transient depolarization event, including polarity reversal, that is conducted along the membrane of a muscle cell or a nerve fiber.

Front 2

Epiphysis

Back 2

The end of a long bone attached to a shaft

Front 3

Haversian Canal

Core of each osteon

Back 3

The canal in the center of each osteon that contains minute blood vessels and nerve fibers that serve the need of the osteocytes.

Front 4

Lamella

Back 4

A layer in the bone matrix in an osteon of compact bone.

Front 5

Osteoclasts

Back 5

Large cells that resorb or break down bone matrix

Front 6

Osteoblasts

Back 6

Bone forming cells
Form bone

Front 7

Bone remodeling

Back 7

Process involving bone formation and destruction (eating) in response to hormonal and mechanical factors.

Front 8

Osteoid

Back 8

Unmineralized bone matrix
Ground substance and collagen fibers which is made and secreted by osteoblasts.

Front 9

Epiphyseal plate

Back 9

Plate of hyaline cartilage at the junction of the diaphysis and epipysis that provides for growth in length of a long bone.

Front 10

diaphysis

Back 10

Elongated shaft of a long bone.

Front 11

Lacunae

Osteocyctes (Mature bone cells) Live here

Back 11

A small space, cavity, or depression;lacunae in bone or cartilage are filled with cells- Bone osteons in lacunae

Front 12

Canaliculus

connect lacunae to eachother and to the central canal

Back 12

Extremely small tubular passage or channel in which nutrients reach the osteocytes of spongy bone by diffusing through the canliculi from capillaries in the endosteum surrounding the trabeculae.

Front 13

Spongy bone

Back 13

Made of Trabeculae
No osteons present here

Front 14

Compact bone

Back 14

Structural unit of compact bone is called the osteon or Haversian system. Bone salts and collagen fibers.

Front 15

Cells responsible for bone growth as part of reabsorption are called

Back 15

Osteoclasts

Front 16

Calcitonin

Back 16

Hormone released by the thyroid that promotes a decrease in calcium levels in the blood.

Front 17

Osteon

Back 17

System of interconnecting canals in the structure of adult compact bone, unit of bone;also called Haversian system.

Front 18

Osteogenesis

Back 18

The process of bone formation; also called ossification.

Front 19

Adrenergic

Back 19

Nerve fibers that release norepinephrine.

Front 20

Cholergenic

Back 20

Nerve endings that upon stimulation release acetylcholine

Front 21

acetycholine (ACh)

Nicotinic

Back 21

Chemical transmitter substance released by some nerve endings.

Front 22

Nicotinic receptors

Back 22

Acetylcholine binding receptors of all autonomic ganglionic neurons and skeletal muscle neuromuscular junctions; named for activation by nicotine.

Front 23

Muscarinic Receptors

Reciprical Inhibition

Back 23

Acetylcholine-binding receptors of the autonomuc nervous system's target organs. Named for activation by the mushroom poison muscarine.

Front 24

Norepinephrine (NE)

Activates sympathetic nervous system

Back 24

A catecholamine neuroransmitter and adrenal medullary hormone, associated with sympathetic nervous system activation

Front 25

Sympathetic Division of the Autonomic nervous system

Uses endocrine system of secreting hormones

Back 25

Prepares the body for activity or to cope with some stressor (danger excitement, etc.) the Fight, fright, and flight subdivision

Front 26

Parasympathetic Divison of the Autonomic Nervous system

Uses endocrine system of internal organs that secrete the hormones for sympathetic system

Back 26

Oversees digesiton, elimination, and glandular function; the resting and digesting subdivision

Front 27

Reticular activating system (RAS)

Back 27

Diffuse brain stem neural network that receives a wide variety of sensory input and maintains wakefuleness of the cerebral cortex.

Front 28

Rapid eye movement (REM) sleep

Back 28

Stage of sleep in which rapid eye movements, and alert EEG (Graphic record of the electrical activity of nerve cells in the brain) pattern, and dreaming occur.

Front 29

Muscle twitch

Back 29

The response of a muscle to a single brief threshold stimulus.

Front 30

Muscle Tone

Back 30

Low levels of contractile activity in relaxed muscle; keeps the muscle health and ready to act.

Front 31

Isometric contrzaction

Back 31

contraction in which the muscle does not shorten (the load is too heavy) but its internal tension increases.

Front 32

Isotonic contraction

Back 32

contraction in which muscle tension remains costant at a given joint angle and load, and the muscle shortens.

Front 33

Creatine phosphate (CP)

Sprinter uses this type of energy. 100 meter dash
Intermediate fatigue

Back 33

Serves as an alternate energy source for muscle tissue.
First 10 seconds.

Oxygen use: NOne
1 ATP per CP, creatine

Front 34

Glycolysis

Waiting for oxygen
30-40 seconds

Short-term bursts of energy
hitting a baseball
Fast glycolic Fibers- Fast fatigue

Back 34

Breakdown of glucose to pyruvic acid- and anaerobic process.

Oxygen use: None
2 ATP per glucose

Front 35

Aerobic respiration

Marathon runner
Muscles have a high percentage of SLOW oxidative fibers 80%
Slow fatigue

Back 35

Energy source: Glucose, pyruvic acid, fatty acids, amino acids.

Oxygen use: Required
38 ATP pre glucose, CO2 H2O

Front 36

Muscle fatigue

Peripheral mechanism.

Back 36

Physiological inability to contract even though the muscle still may be receiveing stimuli. Different from central fatigue in which flesh is still able to perforn but we feel tired.

Front 37

Temporal Summation (time)
Synapse is stimulated a second time BEFORE the initial EPSP dies away= temporal summation = The axon's threshold is reached= tis causes an Action Potential

Back 37

One or more presynaptic neurons transmit impulses in rapid fire order and bursts of neurotransmitter are released in a quick succession. Triggers over and over quickly.

Front 38

Chemical Gated Channels
also called ligand-gated channels

Back 38

Open when the appropriate chemical(usually neurotransmitter)binds.
ex. Neurotransmitter chemical attaches to receptor opens the Sodium/ Potassium Ion channel.

Front 39

Voltage gated ion channel

Back 39

Open in response to changes in the membrane potential.
ex. in depolarization membrane potential becomes less negative as AP moves down membrane (happens in waves).

Front 40

Mechanically gated channels

Back 40

Open in response to to physical deformation of the receptor.
ex. Sensory receptors for touch and pressure.

Front 41

Blood-brain-barrier
Ependymal cells: Make a permeable barrier btwn cerebrospinal fluid and spinal cord.

Back 41

Mechanism that inhibits passage of materials from the blood into brain tissues, reflects relative impermeability of brain capillaries.

Front 42

Accesory nerve cells

Back 42

Considered an accessory part of the vagus nerve, this nerve was formerly called the spinal accessorty nerve.

Front 43

Regulation of temperature
Hypothalimus initiates cooling(sweating) or heat generating mechanisms(shivering)as needed to maintain a relatively constant body temperature.

Back 43

Function of the hypothalimus. Hypothalamic neurons monitor blood temperature and receive impute from other thermoreceptors in the brain and body periphery.

Front 44

Respiration Control
Rate
Depth
Rythm

Back 44

Medulla Oblongata
Respiratory Centers- control the rate and depth of breathing and (with the pons centers) maintain respiratory rhythm.

Front 45

Concussion

Back 45

DEF: Alteration in brain function; usually temporary, following a blow to the head. May cause dizziness, or loss of consciousness. More serious concussions can cause bruising of the brain and permanent neurological damage, called a contusion.