Mcat Biology Lecture 7

Front 1

group of specialized cardiac muscle cells which allows the heart to contract automatically (located in RA)

Back 1

sinoatrial node (SA node)

Front 2

SA node spreads its contractions to the surrounding cardiac muscles via _______________ made from gap junctions

Back 2

electrical synapses

Front 3

slows the rate of heart contractions and increases digestive activity in the intestines

Back 3

vagus nerve (parasympathetic)-innervates the heart and digestive system

Front 4

slower contracting node, causes a delay which allows the atria to finish their contraction, and to squeeze their contents into the ventricles before the ventricles begin to contract

Back 4

atrioventricular (AV) node

Front 5

From the AV node, the AP moves down conductive fibers called the ______________ which is located in the wall separating the ventricles. The AP branches out through the ventricular walls via conductive fibers called ____________, which allow for a more unified, and stronger, contraction of the ventricles.

Back 5

bundle of His
Purkinje fibers

Front 6

blood flows through these away from the heart; they are elastic, and they stretch as they fill with blood. They are wrapped in smooth muscle that is usually innervated by the sympathetic nervous system

Back 6

arteries

Front 7

smaller than arteries, wrapped with smooth muscle

Back 7

arterioles

Front 8

microscopic blood vessels with walls only one cell thick; function in nutrient and gas exchange

Back 8

capillaries

Front 9

contain a far greater volume of blood than arterioles and arteries, also have larger cross sectional area. carries blood toward the heart

Back 9

vein (and venules)

Front 10

carry the most deoxygenated blood in the body

Back 10

pulmonary arteries

Front 11

What is the relationship between cross sectional area vs velocity as blood flows through the body?

Back 11

Front 12

BP is lowest at the ___________

Back 12

capillaries

Front 13

Hypovolemic shock represents a set of symptoms that occur when a patient's blood volume falls abruptly. Hypovolemic shock is most likely to occur during ______

Back 13

arterial bleeding (high blood pressure)

Front 14

skeletal muscle innervated by the phrenic nerve

dome shaped while relaxed, flattens upon contraction, expanding the chest cavity and creating negative gauge pressure

Back 14

diaphragm

Front 15

job is to deliver oxygen to the blood and expel carbon dioxide

Back 15

respiratory system

Front 16

functions of this system are to prepare the air by warming, moistening, and cleaning

Back 16

respiratory tract

Front 17

Microtubules are found in cilia. Ciliated cells are found in the respiratory tract and where else?

Back 17

Fallopian tubes and ependymal cells of the spinal cord. Thus, a problem in microtubule production might result in a problem breathing; or fertility or circulation of cerebrospinal fluid

Front 18

space inside the nose which filters, moistens, and warms incoming air

Back 18

nasal cavity

Front 19

this is at the front of the nasal cavity and it traps large dust particles

Back 19

course hair

Front 20

secreted by goblet cells, traps smaller dust particles and moistens air

Back 20

mucus

Front 21

moves the mucus and dust in the nasal cavity back toward the pharynx, so that it may be removed by spitting or swallowing

Back 21

cilia

Front 22

functions as a passageway for food and air

Back 22

pharynx

Front 23

voice box

Back 23

larynx

Front 24

larynx sits behind the _____________, which is the cartilaginous member that prevents food from entering the trachea during swallowing

Back 24

epiglottis

Front 25

lies in front of the epophagus. composed of ringed cartilage covered by ciliated mucous cells

Back 25

trachea

Front 26

trachea splits into this before entering the lungs

Back 26

right and left bronchi, whch branch many more times to become tiny bronchioles

Front 27

terminate grape-like clusters composed of tiny alveoli

Back 27

branchioles

Front 28

oxygen diffuses from these into a capillary where it is picked up by red blood cells

Back 28

alveoli

Front 29

98% of the oxygen in the blood binds rapidly and reversibly with the protein ___________ inside the erythrocytes forming ______________.

Back 29

hemoglobin-4 subunits, each with a single heme cofactor (organic molecule with an atom of iron at its center)
oxyhemoglobin

Front 30

oxygen dissociation curve shifts right with an _____________ in Co2 pressure, hydrogen ion concentration, or temperature.

Back 30

increase

a shift to the right indicates a lowering of hemoglobin's affinity for Oxygen

Front 31

in the case of acidosis (too much acid in the blood), the body compensates by _________ the breathing rate thereby expelling carbon dioxide and raising the pH of the blood.

Back 31

increasing

Front 32

the greater to pressure of CO2, the ________ the blood content of C02, however when hemoglobin becomes saturated with O2, it's capacity to hold CO2 is __________

Back 32

greater
reduced

Front 33

Nitrogen is stable bc of it's ___________, but doesn't react with the chemicals in the blood. As pressure increases with depth, what happens to the nitrogen concentration in the blood? When the diver comes back up?

Back 33

strong triple bonds

more N2 diffuses into the blood, when the divers come back up the pressure decreases and the gas volume increases (if they come up too fast the N2 won't have time to diffuse out of the blood and into the lungs, and bubbles can form=the bends)

Front 34

What type of system is the lymph system?

Back 34

open: fluid enters at one end and leaves at another end

Front 35

In the lymphatic system, fluid returns to the blood at the _____________ and the ______________.

Back 35

right lymphatic duct
thoracic

Front 36

small portions of membrane-bound cytoplasm torn from megakaryocytes, which contain actin and myosin. They are capable of making protoglandins and some important enzymes

Back 36

platelets

Front 37

what type of tissue is blood?

Back 37

connective

Front 38

what are the important proteins located in the blood plasma?

Back 38

albumin, immunoglobins, and clotting factors

Front 39

transport fatty acids and steroids, also regulate the osmotic pressure in the blood

Back 39

albumin

Front 40

plasm in which the clotting protein __________ has been removed is called ________

Back 40

fibrinogen
serum

Front 41

connective tissue contains what 2 things?

Back 41

cells and a matrix

Front 42

what is the job of the erythrocytes?

Back 42

deliver oxygen and remove carbon dioxide

they do not contain organelles

Front 43

blood cells which contain organelles, but not hemoglobin. What is the function of these cells?

Back 43

leukocytes; protect the body from foreign invaders

Front 44

blood cells differentiate from a common precursor called?

Back 44

stem cell (resides in bone marrow0

Front 45

leukocytes which live a very short time bc they function non-specifically against all infective agents

Back 45

granulocytes

Front 46

leukocytes which live for a long time because they work against specific agents of infection

Back 46

agranulocytes

Front 47

process which involves many factors starting with platelets and also including the plasma proteins prothrombin and fibrin

Back 47

coagulation

Front 48

occurs when an injury to tissue takes place. Causes dilation of blood vessels, increased permeability of capillaries, swelling of tissue cells, and migration of granulocytes and macrophages to the inflamed area

Back 48

inflammation

Front 49

what are the 2 types of acquired immunity?

Back 49

humoral (Beta cell immunity) and cell-mediated (T-cell immunity)

Front 50

each B lymphocyte is capable of making a single type of __________ which it displays on its membrane

Back 50

antibody (or immunoglobulin)

Front 51

foreign body which an antibody recognizes

Back 51

antigen

Front 52

If the B lymphocyte antibody contacts a matching antigen, the B lymphocyte, assisted by a ___________, differentiates into plamsa cells and _____________.

Back 52

helper T cells
memory B cells

Front 53

first time the immune system is exposed to an antigen is known as _______________

Back 53

primary response (requires 20 days to reach its full potential)

next time, effect is faster acting and more potent (secondary response)

Front 54

cell-mediated immunity involves ______, which mature in the thymus

Back 54

T-lymphocytes (never make free antibodies)

Front 55

T lymphocytes that are not destroyed differentiate into ___________ (4).

Back 55

helper T cells, memory T cells, suppressor T cells, killer T cells

Front 56

T-lymphocyte cell which plays a negative feedback role in the immune system

Back 56

Suppressor T cells

Front 57

helper T cells assist in activating ____________ (3)

Back 57

B lymphocytes, killer and suppressor T cells

Front 58

T-lymphocyte cell which binds to the antigen-carrying cell and release perforin. The cells reponsible for fighting some forms of cancer, and for attacking transplanted tissue

Back 58

killer T cells

Front 59

organ which destroys old, worn out red blood cells

Back 59

spleen

Front 60

lymphatic vessels absorb fluid from the interstitial spaces and carry it to the ___________

Back 60

lymphatic ducts, which return it to circulation

Front 61

Type B negative blood will make antibodies that attack ________ antigens but not ___________ antigens

Back 61

type A
type B

Front 62

An individual exposed to a pathogen for the first time will exhibit an innate immune response involving:

Back 62

granulocytes (innate immune system does not involve humoral or cell mediated immunity, it responds to any and every foreign invader)