Test 4 Flashcards
list the types of cellular communication in order of fastest to slowest
direct, synaptic, paracrine/autocrine, endocrine
direct cellular communication
- chemical signals: ions, small solutes, lipid-soluble materials
- exchange between adjacent cells through gap junction
synaptic cellular communication
- chemical signals: neurotransmitters
- exchange across synapse
- found in specific areas, target cell must have appropriate receptors
paracrine cell communication
- chemical signals: paracrine factors
- exchange through ECF (extracellular fluid) to cells that have specific receptors
autocrine cell communication
- similar to paracrine but factors are sent back to the receptors on the same cell
endocrine cell communication
- chemical signals: hormones
- exchange between distant tissues/organs via the bloodstream (circulatory system)
pineal gland
secretes melatonin (circadian rhythms and reproduction)
adrenal glands
secretes hormones for stress, mineral balance, metabolic control
thyroid gland
thyroid hormone, metabolism
Water soluble hormones are associated with ___. Activation of ___ can … ?
- 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
steroid hormones
- lipid soluble
- hormone-receptor complex binds to DNA, altering rate of transcription, translation of proteins
thyroid hormones
- lipid soluble
- bind to mitochondria
- alter gene activity
- can increase ATP production, affects metabolism
Different functions of the regulatory, neural and autonomic centres of the hypothalamus
- 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
TSH
- thyroid stimulating hormone
- targets thyroid gland
ACTH
- adrenocorticotropic hormone
- targets adrenal gland
FSH
- follicle stimulating hormone
- targets ovaries
LH
- luteinizing hormone
- targets testes
GH
- growth hormone
- targets musculo-skeletal system
PRL
- prolactin
- targets mammary gland
MSH
- melanocyte stimulating hormone
list the components of whole blood
- plasma (plasma proteins, other solutes, water)
- formed elements (platelets, white blood cells, red blood cells)
RBC formation
- Day 1: proerythroblast
- Day 2: basophilic erythroblast
- Day 3: polychromatophilic erythroblast
- Day 4: normoblast (nucleus ejected)
- reticulocyte (matures after 24 hrs into RBC)
Where are macrophages found and what do they do ?
- found in bone marrow, spleen, liver
- recycle Fe2+ and Heme
Which surface antigens and antibodies are present in each blood type (A, B, AB, O) ?
- 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)
pulmonary vs systemic circuit
- 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
describe the pathway that blood takes starting from systemic circuit (systemic veins)
- 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)
Why do arteries have a thicker tunica media than veins ?
- since arteries carry blood directly from the heart, it must withstand higher pressures
capillaries lack a ___ ___ and a ___ ___
they lack a tunica externa and tunica media
continuous vs fenestrated capillaries
- continuous capillaries: endothelium is complete lining
- fenestrated capillaries: endothelium is also complete lining but has pores for larger solutes
challenges of the venous system and how they are compensated
- large volume of blood needs to be supported and transported against gravity
- compensated by thicker compliant tunica externa and vasoconstriction
What happens to the venous valves when muscles contract ?
- valves superior to the contracting muscle open
- valves inferior to the contracting muscle close
How is vessel length related to friction ?
- 2x length = 2x resistance = 1/2x flow
How is vessel diameter related to friction ?
- 1/2x diameter = 16x resistance
velocity of blood flow from highest to lowest of the different vessel types
- highest: aorta
- elastic arteries/venae cavae
- muscular artery/veins
- arterioles/venules
- lowest: capillaries
blood pressure is written as:
peak systolic pressure / peak diastolic pressure
tricuspid valve
from RA to RV
pulmonary arteries are ___ and pulmonary veins are ___
- pulmonary arteries are deoxygenated
- pulmonary veins are oxygenated
bicuspid valve
from LA to LV
list the 8 steps of the cardiac cycle
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
stroke volume (SV)
- amount of blood pumped out of ventricles in a single heartbeat
- SV = EDV – ESV
cardiac output (CO)
- amount of blood pumped by left ventricle to aorta each minute
- CO = HR x SV
What do the following centres of the medulla oblongata do ?
respiratory, cardioacceleratory, cardioinhibitory, vasomotor
- 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
What do epinephrine and thyroxine do ?
increase heart rate
central regulation (neural and endocrine)
- 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
erythropoiesis
process that produces red blood cells
transferrin
plasma protein that binds and transports Fe2+
