Biology: Lecture 7: The Cardiovascular System; The Respiratory System

Front 1

The circulatory path of the blood

Back 1

Beginning with the left ventricle, blood is pumped, through the aorta. From the aorta --> smaller arteries --> arterioles --> capillaries --> venules --> veins --> superior and inferior vena cava --> right atrium --> right ventricle --> pulmonary arteries --> arterioles --> capillaries of lungs --> venules --> veins --> pulmonary veins --> left atrium --> left ventricle

Front 2

Systole

Back 2

Occurs when ventricles contract

Front 3

Diastole

Back 3

Occurs during relaxation of entire heart, and then contraction of the atria.

Front 4

Sinoatrial Node (SA Node)

Back 4

-The heart contracts automatically, paced by a group of specialized cardiac cells called SA nodes, located in the right atrium.
-The SA Node is autorhythmic, spreading its contractions to the surrounding cardiac muscles via electrical synapses made from gap junctions.

Front 5

Vagus Nerve

Back 5

-Parasympathetic vagus nerve innervates the SA node, slowing contractions.

Front 6

Atrioventricular Node (AV Node)

Back 6

-The action potential generated by the SA node spreads around both atria causing them to contract, and, at the same time, spreads to the AV node, located in the interatrial septa. It is slower to contract.

Front 7

Bundle of His

Back 7

-From the AV node, the action potential moves down these conductive fibers. Located in the wall separating the ventricles.

Front 8

Purkinje Fibers

Back 8

-The action potential branches out through the ventricular walls via these conductive fibers. They allow for a more unified, stronger connection.

Front 9

Arteries

Back 9

-Wrapped in smooth muscle that is innervated by sympathetic nervous system (epinephrine = powerful vasoconstrictor)

Front 10

Arterioles

Back 10

-Wrapped in smooth muscle. Constriction and dilation of arterioles can be used to regulate blood pressure as well as rerouting blood.

Front 11

Capillaries

Back 11

-Nutrient and gas exchange with any tissue other than vascular tissue takes place across these walls. There are four methods for capillary movement: 1) pinocytosis 2) diffusion or transport through capillary cell membranes 3) movement through pores in the cells called fenestrations 4) movement through the space between cells

Front 12

As blood flows into a capillary:

Back 12

hydrostatic pressure is greater than osmotic pressure, and net fluid flow is out of capillary, and into the interstitium.

Front 13

Venules and Veins

Back 13

-Lumen larger than ones on arteries, contain more volume of blood

Front 14

T or F: The cross-sectional area of capillaries is far less than the are of arteries or veins

Back 14

F: much greater

Front 15

Relationship between blood velocity w/ cross-sectional area

Back 15

blood velocity is inversely proportional to cross-sectional area

Front 16

Blood pressure ___________ near the heart and __________ to the _________ near the capillaries

Back 16

increases, decreases, lowest

Front 17

Inspiration

Back 17

Occurs when the medulla oblongata of the midbrain signals the diaphragm to contract.

Front 18

Diaphragm

Back 18

Skeletal muscle, and innervated by the phrenic nerve. When relaxed, it is dome-shaped, flattens upon contraction (creating negative gauge pressure)

Front 19

Nasal Cavity

Back 19

Filters, moistens, and warms incoming air. Also, coarse hair at the front traps large dust particles. Mucus secreted by goblet cells traps smaller dust particles and moistens the air, and cilia moves mucus and dust back toward pharynx, so it can be removed by spitting/swallowing.

Front 20

Pharynx

Back 20

(Throat) - Functions as a passageway for food and air.

Front 21

Larynx

Back 21

(Voice Box) - Sits behind the epiglottis, contains vocal cords. Also, when nongaseous materials enter the larynx, a coughing reflex is triggered.

Front 22

Trachea

Back 22

(Wind Pipe) - Lies in front of esophagus, composed of ringed cartilage covered by ciliated mucous cells. Splits into right and left bronchi before entering lungs.

Front 23

Alveoli

Back 23

From each alveolus, oxygen diffuses into a capillary where it is picked up by RBC's. These release CO2, which diffuses into the alveolus, and is expelled upon exhalation.

Front 24

What might result from a problem in microtubule production?

Back 24

A problem in breathing (or fertility or circulation of cerebrospinal fluid)

Front 25

As O2 pressure increases, the O2 saturation of hemoglobin:

Back 25

increases sigmoidally

Front 26

What does the oxygen saturation of hemoglobin depend upon?

Back 26

CO2 pressure, pH, and temp of blood.

Front 27

The oxygen dissociation curve is shifted to the right by what?

Back 27

An increase in CO2 pressure, hydrogen ion conc, or temperature (indicates a lowering of hgb's affinity for oxygen).

Front 28

What does carbon monoxide do?

Back 28

Has more than 200 times affinity for hgb than does oxygen but shifts the oxygen dissociation curve to the LEFT.

Front 29

Carbon dioxide is carried by the blood in three forms:

Back 29

1) in physical solution
2) as bicarbonate ion (the most)
3) in carbamino compounds (combined with hgb + other proteins)

Front 30

Carbonic Anhydrase

Back 30

-The bicarbonate ion formation is governed by this enzyme in the reversible reaction:


When CO2 is absorbed in in the lungs, bicarbonate ion diffuses into the cell. To balance, Cl moves out of cell (chloride shift).

Front 31

The greater the pressure of CO2, the greater the:

Back 31

blood content of CO2

Front 32

When hgb becomes saturated w/ oxygen, its capacity to hold CO2 is ________.

Back 32

reduced (Haldane effect)

Front 33

Acidosis (too much acid in blood)

Back 33

The body compensates for this by increasing the breathing rate thereby expelling CO2 and raising the pH of the blood.

Front 34

The Rate of Breathing

Back 34

-Affected by the central chemoreceptors located in the medulla, and peripheral chemoreceptors located in the carotid arteries and aorta (central and peripheral chemoreceptors monitor CO2 conc in blood and increase breathing when levels get too high).

Front 35

The Bends (decompression sickness)

Back 35

Caused by, among other things, when divers go too deep, nitrogen diffuses into the blood; when they come back up (if they dont allow enough time) bubbles form, which may block vessels causing decompression sickness.

Front 36

The Lymphatic System

Back 36

Collects excess interstitial fluid and returns it to the blood. Proteins and large particles that cannot be taken up by the capillaries, are removed by the lymph system.

Front 37

T or F: The lymph system recycles the interstitial fluid and monitors the blood for infection

Back 37

True

Front 38

T or F: The lymph system reroutes high soluble fat digestates around the small veins of the intestine into the larger capillaries of the neck.

Back 38

False: The lymph system reroutes LOW soluble fat digestates around the small CAPILLARIES of the intestine into the larger VEINS of the neck.

Front 39

The lymph system is an _________ system.

Back 39

OPEN (fluid enters at one end and leaves at the other)

Front 40

Factors that affect interstitial pressure:

Back 40

1) blood pressure
2) plasma osmotic pressure
3) interstitial osmotic pressure
4) permeability of capillaries

Front 41

Lymph Flow

Back 41

Intermittent valves allow fluid to flow in only one direction, and it is propelled through valves in two ways: 1) smooth muscle in the walls of larger lymph vessels contract when stretched 2) lymph vessels may be squeezed by adjacent skeletal muscles, body movements, etc

Front 42

Draining of the Lymph System

Back 42

The lymph system empties into larger veins at the thoracic duct and the right lymphatic duct. Lymph from the right arm and head enter the blood through the right lymphatic duct. The rest of the body is drained by the thoracic duct.

Front 43

What kind of tissue is the blood?

Back 43

Connective Tissue

Front 44

When a blood sample is placed in a centrifuge, it separates into 3 parts:

Back 44

1) plasma
2) buffy coat (WBC's)
3) RBC's

Front 45

Hematocrit

Back 45

The percentage by volume of RBC's (usually 35-50% and greater in men than women)

Front 46

Plasma

Back 46

contains the matrix of the blood, which includes water, ions, urea, ammonia, proteins (albumin, immunoglobulins, clotting factors), and other organic and inorganic compounds

Front 47

Albumin

Back 47

Transports fatty acids and steroids, as well as acting to regulate the osmotic pressure of the blood.

Front 48

Serum

Back 48

Plasma in which the clotting protein fibrinogen has been removed.

Front 49

Where are albumin, fibrinogen, and most other plasma proteins formed? What function?

Back 49

In the liver. They act as a source of amino acids for tissue protein replacement.

Front 50

Erythrocytes (RBC's)

Back 50

-No organelles or nucleus, so don't do mitosis
-Transport O2 and CO2

Front 51

Leukocytes (WBC's)

Back 51

-No organelles
-Function to protect the body from foreign invaders)

Front 52

Stem Cells

Back 52

-Precursor cell that resides in bone marrow, from which all blood cells differentiate from

Front 53

Granulocytes

Back 53

-Type of leukocyte that live a short time, cuz multiply quickly against any infection, and then die once it's gone

Front 54

Agranular Leukocytes

Back 54

-Type of leukocyte that live a long time, work against specific agents of infection

Front 55

Platelets

Back 55

-Small portions of membrane-bound cytoplasm torn from megakaryocytes (from bone marrow)
-No nucleus, have actin and myosin
-Membrane designed to not adhere to healthy endothelium, but adhere to injured endothelium

Front 56

Coagulation (3 steps)

Back 56

1) Many coagulation factors form a complex called prothrombin activator 2) This catalyzes the conversion of prothrombin into thrombin 3) Thrombin is an enzyme that governs polymerization of fibrinogen to fibrin threads that attach to platelets to form tight plug.

Front 57

Which leukocyte is most abundant in blood?

Back 57

Neutrophils (62%)

Front 58

Which leukocyte is least abundant in blood?

Back 58

Basophils (0.4%)

Front 59

The human body protects itself from infectious microbes and toxins in two ways:

Back 59

1) Innate immunity
2) Acquired immunity

Front 60

Innate Immunity

Back 60

Involves a generalized protection from most intruding organisms and toxins.

Front 61

Acquired Immunity

Back 61

Protection against specific organisms or toxins. Develops after the body is FIRST attacked.

Front 62

Inflammation

Back 62

-Results from injury to tissue. Blood vessels dilate, capillaries increase permeability, tissue cells swell, and granulocytes and macrophages migrate to inflamed area.
-Walls off effected tissue, impeding spread of infection