Answer:
Action potentials travel along the axon.
Explanation:
Action potential produces in four steps:
(1) Depolarization to the threshold.
(2) Activation of the Na+ channel and rapid depolarization.
(3) Inactivation of Na+ channel and activation of the K+ channel.
(4) Return to normal permeability.
The action potential travels by an unmyelinated axon. Their only 1 segment of the axon affects by the action potential. Then a local current helps to depolarize another segment to the threshold and again cycle repeats.
Another is an action potential travel by a myelinated axon. In this, the current is generated by the action potential and jumps from the node of Ranvier to the next segment.
Answer:
A. Cholecalciferol, or vitamin D3, is necessary for the normal absorption of calcium and phosphate ions. Vitamin D3 is made by cells in the epidermis due to exposure to sunlight. Without enough exposure to sunlight, the body won't produce enough vitamin D3
Explanation:
Hydroxyapetite is the organic mineral in the bone that maintain the mechanical strengthening of the bone, by interacting with collagen fibres. Calcium and Phosphate ions are the two major components of this bone materials. Generally 90%of bone is calcium , while 80% is phosphate. Phosphate stimulate growth of Oesteocytes. And the latter is important for bone mineralization. Together they maintain bone mineralization and maintenance,thereby preventing bone resorption.
Absorption of Ca and P. into the blood stream to reach the bones cells is conducted by Vit D. Dietary supply is not the only route through which Vit D get to the blood stream. Exposure of the skin to UVB rays of the early morning sunlight is another route.
Vitamin D plays major role in absorption of Ca and P in the body.
Vit. D is naturally synthesized in humans when the skin is exposed to early morning sunlight (UVB). It is usually produce in inactive forms,and undergoes hydroxylation( i.e addition of hydroxyl group -OH) in the liver to be biologically active .
Its active forms acts on the epithelial cells of the intestinal wall to facilitate calcium absorption into the blood stream to reach the bone cells .it also stimulate absorption of Phosphate.
Since these two minerals ensures, mechanical strength, prevention of bone resorption, there availability in the bone must be maintained by Vit, D supply from exposure to sunlight.
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Answer:
B. Mitochondrion
Explanation:
The Krebs Cycle occurs in the mitochondria during the processes of cellular respiration.
Specifically, it occurs in the matrix of the mitochondria.
Answer:The question is incomplete because the options are not given. Here are the options.
a. The level of energy available in the ecosystem would increase, which would cause the population of autotrophs to increase.
b. The level of available nutrients in the soil would decrease, which would cause the population of producers to decrease
C. The population of primary consumers would increase because of increased production by autotrophs.
d. The population of primary consumers would increase because of decreased competition from decomposers.
The current answer is option B.
The level of available nutrients in the soil would decrease, which would cause the population of producers to decrease.
Explanation:
This is because when the soil is acidic it will reduce the availability of plants nutrients in the soil and it will result in accumulation of toxic chemicals which can affect the growth of plants.
If nutrients are not available for plants growth which is primary producer, it will result in poor growth, low photosynthesis and hence the production of glucose will be reduced because nutrients is essential for plants growth.
