Answer:
The membrane potential of a nerve cell will depolarize if there is an increase in the positive ions inside the cell.
Explanation:
When nerves are in resting potential it is -70mV. In this stage interior of the cell is negatively charged and outside is more positive. When depolarization occurs the inside cell becomes positive.
This is due to the rush of sodium ions into the cell by voltage-gated channels. Now the inside charge is more positive and the chloride ions move out of the cell. Thus outside becomes more negative.
After some time of depolarization stage, potassium ions move out of the cell making the nerve cell again negative. Now the depolarized stage becomes repolarized by the entry of potassium ions.
During depolarization, the potential of the cell is -55mV. When repolarization occurs, it is again -70mV. But the potassium channels are open and some of the potassium ions move out of the cell making the inside environment more negative. This is known as hyperpolarization condition.
This hyperpolarization remains for a short period where action potential can't occur. This period is called the refractory period. Again potassium ions enter into the cell. This results in the resting potential of the neuron again.
The theory that a drug attaches itself to specialized cells in the body because of its size, shape, electrical charge, and chemical properties is called receptor site theory.
c.
Answer:
The food chain that is described in the question is called Grazing food chain.
Explanation:
Grazing food chain is a type of food chain that contain producers at the lowest tropic level.The producers can manufacture their own food by photosynthesis process. Here grass act as producers.
The second topic level of grazing food chain contain primary consumers which consume producer. Here grasshopper eat grass,as a result grasshopper act as primary consumers or herbivores
The third tropic level of grazing food chain contain secondary consumers that feed on primary consumers. Here snake eats grasshopper,as a result snake act as secondary consumers or primary carnivores.
The highest tropic level of grazing food chain contain tertiary consumers or secondary carnivores.Hawk eats snake,as a result hawk act as Tertiary consumers or secondary carnivores.
<span>The
answer is a fecal occult blood test (FOBT) that checks for hidden (occult)
blood in the stool (feces) by use of a microscope. The major disadvantage is that it is not very
accurate because it is not a 100% reliable as an indicator of colorectal
cancer. Sigmoidoscopy is often undertaken following a positive FOBT</span>
Answer: Fibrous Protein is the correct answer
Explanation:
