bio exam 3 - chap 44 first few slides + HW/quizses

arise from receptors located throughout the body (temperature, pressure, touch, vibration, pain, awareness of body positions)

somatic sensations

arise from receptors restricted to specific areas of the body (taste, smell, hearing, balance, vision)

special senses

respond to distortion caused by pressure. → Force stretches the membrane & cytoskeleton, which pulls on and opens stretch sensitive ion channels to start an action potential in sensory neuron.

-Found in joints, muscles, and tendons

mechanoreceptors

detect changes in temperatures → Proteins in which the structure changes shape under different levels of energy. different channels will open in response to specific temperature ranges creating very short action potentials. Found near the skin or organ surface.

thermoreceptors

detect specific molecules

chemoreceptors

detect electric fields

electroreceptors

detect magnetic fields

magnetoreceptors

respond to particular wavelengths of light

photoreceptors

mechanoreceptors that monitor muscle length

muscle spindles

Thermoreceptor that opens allowing Ca+ into the cell in response to heat or certain chemicals. → Thermoreceptor that opens allowing Ca+ into the cell in response to heat or certain chemicals.

VRL-1 (TRPV1)

what is the functional unit of the kidney

nephron

what would happen if the glomerulus became clogged

a) potassium levels would decrease (hypokalemia) as distal flow increases and promotes K+ secretion

b) oliguria (low urine output)

c) the kidney would shift filtration toward the distal tubule, keeping overall filtration normal

d) blood pressure would drop due to enhanced sodium and water excretion

B

what protein drives the first step in tubular reabsorption by creating an ion gradient?

sodium potassium pump

what metabolic process produce nitrogenous waster, which occurs when an amino group is removed from an amino acid

deamination

predict what would happen to the resting potential of an axon if facilitative potassium channels were blocked

a) the resting potential would be much less negative because K+ could no longer leak out of the cell
b) the resting potential would not change because it is maintained solely by the sodium potassium pump

c) the resting potential would be more negative because K+ could no longer leak out of the cell

d) the resting potential would shift closer to the potassium equilibrium potential

A

at resting potential, where is sodium concentration higher

outside the cell

what role does calcium play in transmitting a signal across a synapse?

a) depolarizes the postsynaptic cell

b) changes the structure of retinal protein in eye neurons, which opens nearby sodium channels

c) cause the release of packets of neurotransmitters across the synapse
d) hyperpolarizes the postsynaptic cell and prevent signal transmission

c

low glutamate levels control some forms of depression, what would be the mechanism behind this disorder?

a) glutamate release from presynaptic neurons causes neuronal damage

b) loss of GABAergic inhibition

c) fewer action potentials being generated
d) excessive dopamine synthesis secondary to glutamate dopamine pathway stimulation

c

Which of the following is not one of the 3 main types of plastids found in plants

a) chloroplasts

b) chromoplasts
c) cytoplasts

d) leucoplasts

c

when did a permanent primary endosymbiosis of a cyanobacteria occur in the ancestor of land plants, thereby giving rise to plastids?

1.6 Ga

plastids that synthesize and store starch

amyloplasts

green plastids that perform photosynthesis

chloroplasts

plastids that synthesize and store proteins

proteinoplasts

plastids that synthesize and store lipids

elaioplasts

Predict how the thickness of the cuticle and the number of stomata differ in plants from wet habitats versus dry habitats.

a) Plants from dry habitats should have thinner cuticle and more stomata.

b) Plants from wet habitats should have thinner cuticle and more stomata.

c) Plants from dry habitats should have thicker cuticle and more stomata.

d) Plants from wet habitats should have thinner cuticle and fewer stomata.

e) Plants from wet habitats should have thicker cuticle and fewer stomata. 

b

Consider a tree that is 50m tall and is transpiring roughly 80 liters of water each day. The specific heat capacity of water is 4.2 joules per gram per Celsius degree or 1 calorie per gram per degree Celsius. 

a) ~ 580 calories per gram of water

b) ~3,260 calories
c) ~46,000 food Calories per day
d) 0

d

Biologists have been able to produce mice that lack functioning genes for aquaporins. How would the urine of these mice compare to that of mice with normal aquaporins?

a) lower volume and lower osmolarity

b) lower volume and higher osmolarity
c) higher volume and lower osmolarity
d) higher volume and higher osmolarity

c