Question

Imagine if you could tinker with any component of the signal transduction pathway involved in vision...

Imagine if you could tinker with any component of the signal transduction pathway involved in vision in vertebrates. In this problem, you will predict the effect of a change in the activity of a single component of the signal transduction pathway in vision. The rod cell secretes the neurotransmitter glutamate onto the bipolar cell as a function of its membrane potential – the more depolarized, the more it secretes; the more hyperpolarized, the less it secretes. The bipolar cell in this case (ON bipolar) has glutamate receptors that cause closure of cation channels, hyperpolarizing their membrane. They synapse with ON ganglion cells and secrete acetylcholine into the synapse at a rate that increases with increased depolarization of the bipolar cell membrane. The ON ganglions have acetylcholine receptors that are ligand-gated ion channels. The ganglion cell responds by sending a train of action potentials to the brain; the frequency of these action potentials is a function of the amount of acetylcholine that they sense. In your experiment, you will expose the rod cells to a controlled light pulse (same length and intensity every time) and measure the output of the ON ganglion cells to which they are connected. Then you will repeat this in each perturbed system.

- The acetylcholine receptor binds acetylcholine, causing it to

a. pump k+ ion out on the cell

b. change into the open conformation allowing Na+ ion to inter the cell

c. change into the closed conformation, stopping the leak of Na+ ions into the cell

Homework Answers

Answer #1

Answers

b. change into the open conformation allowing Na+ ion to enter the cell

Explanation: The binding of acetylcholine to the acetylcholine receptor opens the sodium ion channels and allowing more sodium inside the cell. This leads to the depolarization of the membrane potential, which results in more glutamate secretion by bipolar cell and hence more acetylcholine secretion. This will keep signal ON.

Explanation for wrong answers

a. The role of K+ channel is not reported in the literature for the acetylcholine signaling response. At synapse, more Na+ ion channels are present than K+

c. acetylcholine plays a role in the propagation of signal. If the channel will be closed, then hyperpolarization of the membrane takes place. This leads to less acetylcholine production and hence signal will turn OFF.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
1.Which one of the following is INCORRECT about kidney function? Select one: a. Angiotensin II can...
1.Which one of the following is INCORRECT about kidney function? Select one: a. Angiotensin II can directly constrict blood vessels b. Aldosterone has a major role in water reabsorption c. Antidiuretic hormone acts in the collecting ducts to increase water reabsorption d. A small quantity of filtrate is reabsorbed in the renal pelvis e. There is major reabsorption of sodium ions in the proximal tubule 2.Which one of the following is correct? Select one: a. Angiotensin II is a potent...
7.)In G proteins, which form of the guanyl nucleotide is bound in the unactivated state? a.)...
7.)In G proteins, which form of the guanyl nucleotide is bound in the unactivated state? a.) GTP b.) GDP c.) GMP d.) dGTP e.) None of above 8.)which of the following amino acids can be phophorylated? a.) tyrosine, serine, theronine b.) tyrosine, serine, tryptophan c.) serine, threonine, asparagine d.) histidine, serine, phenylalanine e.) tyrosine, methionine, typrtophan 9.) most signal molecules: a.)easily diffuse through the membrane and bind to a receptor in the cytoplasm b.) bind to membrane receptors and transmit...
1. Which sentence best defines signal transduction in a biochemical context? a. Alteration of cell functions...
1. Which sentence best defines signal transduction in a biochemical context? a. Alteration of cell functions in response to the environment b. Generation of a chemical change in response to information c. Induction of cell death upon nutrient starvation d. Responses to stimuli 2. Which statement is correct? a. G protein-coupled receptors produce second messengers indirectly while receptor enzymes catalyse second messenger generation b. Second messengers stimulate the activity of G protein-coupled receptors. c. Receptor enzymes produce second messengers through...
7. Which of the following ion(s) is in highest concentration outside the neuron cell membrane in...
7. Which of the following ion(s) is in highest concentration outside the neuron cell membrane in a resting state? a. Chloride (Cl) and potassium (K) b. Potassium (K) only c. Magnesium (Mg2) d. Chloride (Cl) and sodium (Na) e. Nitric oxide (NO) 8. A neurotransmitter may be described as “excitatory” (leads to depolarization) or “inhibitory” (no change or hyperpolarization). Which of the following determines the action of the neurotransmitter? a. The type of charges (or¨)on the neurotransmitter b. The type...
QUESTION 10 Which of the following proteins are active during anaerobic fermentation? myokinase protease acetylcholinesterase phosphatse...
QUESTION 10 Which of the following proteins are active during anaerobic fermentation? myokinase protease acetylcholinesterase phosphatse 2 points    QUESTION 11 _____________ has the greatest influence on resting membrane potential. Sodium Chloride Magnesium Potassium 2 points    QUESTION 12 Ribosomes are in the ___________________. soma axon hillock dendrite axon 2 points    QUESTION 13 A mixed nerve has only efferent neurons. True False 2 points    QUESTION 14 Myoglobin is a protein that binds oxygen. True False 2 points   ...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT