Free Biology 30 Tutoring In Alberta

  0

0 Tutors Online Right Now

  0

Go Ahead - Ask A Question

* You can add tags to identify the topic of your post. Tags will autofill if they have been used before.
Displaying 1-10 of 190 results.

What effect does increasing GnRh have on: 

a) fsh

b) LH

Posted 3 years ago by Jasmine101 in Biology 30 | 4 answers
#female reproduction 

Which of the following choices correctly describes the sensory pathway?
Select one:
a. Sensory neuron → brain → motor neuron
b. Sensory receptors → sensory pathway → parietal lobe → motor pathway → muscles
c. Sensory neuron → spinal cord → motor neuron
d. Sensory receptors → sensory pathway → spinal cord → motor pathway → muscles
 

All of the following statements correctly describe a polarized membrane EXCEPT which?

Select one:
a. An RMP of –60 mV indicates that there are more positive ions inside the axon than an RMP of –70 mV.
b. There is a difference in the charges found on the inside of the membrane to the outside.
c. A resting membrane potential (RMP) of –90 mV indicates the there are more positive ions inside the axon than an RMP of –70 mV.
d. There is a separation of the charge by a membrane, resulting in its ability to do work.
 
 

Events in Visual Perception 

Potassium channels opens, allowing potassium ions to move out. Some sodium channels open in the dendrite. All ion channels close and the Na+/K+ exchange pump starts working. Sodium ions diffuse toward the first node of Ranvier in the axon Lights hit the retina. The threshold level is reached at the first node of Ranvier in the axon Sodium channels open in the neural membrane of the axon, allowing the remaining sodium ions to move in.

List, in order, the events in visual perception that must occur for a person to see an object: AnswerAnswerAnswerAnswerAnswerAnswer, and Answer.

Posted 2 years ago by aliya in Biology 30 | 0 answers
#brain #neuron #and sensory pathways #polarized 

The nerve impulses always travel in one direction from dendrites to axon terminals. What prevents an action potential from travelling backward?

Select one:
a. Hyperpolarization of the neuron makes the membrane more positive and prevents another action potential.
b. After repolarization, the reversal of ions prevents another action potential as there would not be enough sodium ions outside the cell to rush in.
c. After repolarization, the refractory period occurs, where the sodium ions are found outside the cell.
d. The refractory period prevents another action potential by lowering the threshold potential. My answer is B but not sure if its correct or not. 
 

When a single photon from a source of light hits the retina in the eye, it triggers a signal that travels along the optic nerve to the occipital lobe of the brain. 

The interaction of a photon with the photoreceptors in the retina first causes the movement of sodium ions into a sensory neuron. What happens after the movement of sodium ions?

Select one:
a. Sodium ions move out of a sensory neuron.
b. Potassium ions move into an interneuron.
c. Potassium ions move out of a sensory neuron.
d. Sodium ions move into an interneuron. 
my answer is c but not sure if its correct or not 
 
 
 
 

 

A neuron was isolated from structure number 3 in the diagram above. 

When comparing the velocity of action potentials, structure numbered 3 is much slower than that of structure numbered 4. 

Which of the following explains why this is?

Select one:
a. Structure number 3 has a larger diameter than structure number 4.
b. Structure number 4 does not have myelin sheaths.
c. Structure number 3 does not have myelin sheaths.
d. Structure number 4 has a larger diameter than structure number 2. I put C for this but again not sure if my answer is correct. 

Posted 2 years ago by aliya in Biology 30 | 0 answers
#brain #neuron #action potential #repolarized #depolarization #membrane