Test 4

Question 1

list the types of cellular communication in order of fastest to slowest

Answer 1

direct, synaptic, paracrine/autocrine, endocrine

Question 2

direct cellular communication

Answer 2

• chemical signals: ions, small solutes, lipid-soluble materials
• exchange between adjacent cells through gap junction

Question 3

synaptic cellular communication

Answer 3

• chemical signals: neurotransmitters
• exchange across synapse
• found in specific areas, target cell must have appropriate receptors

Question 4

paracrine cell communication

Answer 4

• chemical signals: paracrine factors

- exchange through ECF (extracellular fluid) to cells that have specific receptors

Question 5

autocrine cell communication

Answer 5

• similar to paracrine but factors are sent back to the receptors on the same cell

Question 6

endocrine cell communication

Answer 6

• chemical signals: hormones

- exchange between distant tissues/organs via the bloodstream (circulatory system)

Question 7

pineal gland

Answer 7

secretes melatonin (circadian rhythms and reproduction)

Question 8

adrenal glands

Answer 8

secretes hormones for stress, mineral balance, metabolic control

Question 9

thyroid gland

Answer 9

thyroid hormone, metabolism

Question 10

Water soluble hormones are associated with ___. Activation of ___ can … ?

Answer 10

• receptors associated with G proteins the regulate secondary messengers
• activation of G protein can either:
  1) increase cAMP production, activating enzymes
  2) increase cAMP breakdown, inhibiting enzymes
  3) release stored Ca2+/open Ca2+ channels, activating enzymes

Question 11

steroid hormones

Answer 11

• lipid soluble

- hormone-receptor complex binds to DNA, altering rate of transcription, translation of proteins

Question 12

thyroid hormones

Answer 12

• lipid soluble
• bind to mitochondria
• alter gene activity
• can increase ATP production, affects metabolism

Question 13

Different functions of the regulatory, neural and autonomic centres of the hypothalamus

Answer 13

• regulatory hormones released to anterior pituitary through hypophyseal portal system
• neural: secrete ADH and OXT through posterior pituitary
• autonomic: direct neural control over adrenal gland, release of epinephrine and norepinephrine

Question 14

TSH

Answer 14

• thyroid stimulating hormone

- targets thyroid gland

Question 15

ACTH

Answer 15

• adrenocorticotropic hormone

- targets adrenal gland

Question 16

FSH

Answer 16

• follicle stimulating hormone

- targets ovaries

Question 17

LH

Answer 17

• luteinizing hormone

- targets testes

Question 18

GH

Answer 18

• growth hormone

- targets musculo-skeletal system

Question 19

PRL

Answer 19

• prolactin

- targets mammary gland

Question 20

MSH

Answer 20

• melanocyte stimulating hormone

Question 21

list the components of whole blood

Answer 21

• plasma (plasma proteins, other solutes, water)

- formed elements (platelets, white blood cells, red blood cells)

Question 22

RBC formation

Answer 22

• Day 1: proerythroblast
• Day 2: basophilic erythroblast
• Day 3: polychromatophilic erythroblast
• Day 4: normoblast (nucleus ejected)
• reticulocyte (matures after 24 hrs into RBC)

Question 23

Where are macrophages found and what do they do ?

Answer 23

• found in bone marrow, spleen, liver

- recycle Fe2+ and Heme

Question 24

Which surface antigens and antibodies are present in each blood type (A, B, AB, O) ?

Answer 24

• Type A: surface antigen A, anti-B antibodies
• Type B: surface antigen B, anti-A antibodies
• Type AB: both A and B surface antigens, no antibodies (universal acceptor)
• Type O: no surface antigens, both anti-A and anti-B antibodies (universal donor)

Question 25

pulmonary vs systemic circuit

Answer 25

- pulmonary circuit: carries blood to and from gas exchange areas of the lungs - systemic circuit: transports blood to and from the rest of the body

Question 26

describe the pathway that blood takes starting from systemic circuit (systemic veins)

Answer 26

- systemic circuit (veins) - right atrium - right ventricle - pulmonary circuit (pulmonary arteries, capillaries in the lungs, pulmonary veins) - left atrium - left ventricle - systemic circuit (systemic arteries, capillaries of body, systemic veins)

Question 27

Why do arteries have a thicker tunica media than veins ?

Answer 27

- since arteries carry blood directly from the heart, it must withstand higher pressures

Question 28

capillaries lack a ___ ___ and a ___ ___

Answer 28

they lack a tunica externa and tunica media

Question 29

continuous vs fenestrated capillaries

Answer 29

- continuous capillaries: endothelium is complete lining | - fenestrated capillaries: endothelium is also complete lining but has pores for larger solutes

Question 30

challenges of the venous system and how they are compensated

Answer 30

- large volume of blood needs to be supported and transported against gravity - compensated by thicker compliant tunica externa and vasoconstriction

Question 31

What happens to the venous valves when muscles contract ?

Answer 31

- valves superior to the contracting muscle open | - valves inferior to the contracting muscle close

Question 32

How is vessel length related to friction ?

Answer 32

- 2x length = 2x resistance = 1/2x flow

Question 33

How is vessel diameter related to friction ?

Answer 33

- 1/2x diameter = 16x resistance

Question 34

velocity of blood flow from highest to lowest of the different vessel types

Answer 34

- highest: aorta - elastic arteries/venae cavae - muscular artery/veins - arterioles/venules - lowest: capillaries

Question 35

blood pressure is written as:

Answer 35

peak systolic pressure / peak diastolic pressure

Question 36

tricuspid valve

Answer 36

from RA to RV

Question 37

pulmonary arteries are ___ and pulmonary veins are ___

Answer 37

- pulmonary arteries are deoxygenated | - pulmonary veins are oxygenated

Question 38

bicuspid valve

Answer 38

from LA to LV

Question 39

list the 8 steps of the cardiac cycle

Answer 39

1) all chambers relaxes and ventricles partially filled 2) atrial systole: atria contract, AV valves open and fill ventricles with blood 3) atrial diastole 4) ventricular systole (1st phase): isovolumetric contraction (AV valves are closed) 5) ventricular systole (2nd phase): semilunar valves open and blood forced out of ventricles (ventricular ejection) 6) ventricular diastole (early): SL valves close 7) isovolumetric relaxation: blood flow into relaxed atria but AV valves still closed 8) ventricular diastole (late): all chambers relaxed

Question 40

stroke volume (SV)

Answer 40

- amount of blood pumped out of ventricles in a single heartbeat - SV = EDV – ESV

Question 41

cardiac output (CO)

Answer 41

- amount of blood pumped by left ventricle to aorta each minute - CO = HR x SV

Question 42

What do the following centres of the medulla oblongata do ? | respiratory, cardioacceleratory, cardioinhibitory, vasomotor

Answer 42

- respiratory centre: increase respiratory rate - cardioacceleratory and cardioinhibitory: increase cardiac output (CO) and blood pressure (BP) - vasomotor: vasoconstriction (= increase CO and BP) - all these together increase pH and O2, decreasing CO2

Question 43

What do epinephrine and thyroxine do ?

Answer 43

increase heart rate

Question 44

central regulation (neural and endocrine)

Answer 44

- endocrine mechanisms: long term increases in BV and BP - neural mechanisms: activation of cardiovascular centre in medulla oblongata to cause short term increase in BP by stimulation of heart and vasoconstriction

Question 45

erythropoiesis

Answer 45

process that produces red blood cells

Question 46

transferrin

Answer 46

plasma protein that binds and transports Fe2+