Answer:
A plant cell contains a large, singular vacuole that is used for storage and maintaining the shape of the cell. In contrast, animal cells have many, smaller vacuoles. Plant cells have a cell wall, as well as a cell membrane. In plants, the cell wall surrounds the cell membrane.
Explanation:
Foods that contain substantial amounts of vitamin A include beef liver, spinach, broccoli and liver oil.
<h3>What is vitamin A?</h3>
Vitamin A is a fundamental micronutrient that must be ingested in the diet in suitable amounts.
Leafy green vegetables (such as spinach) or orange vegetables (such as carrots) contain many vitamin A.
Vitamin A benefits include:
- supports the immunity
- reduces ac_ne
- supports bones
Learn more about vitamin A here:
brainly.com/question/9179407
Answer:
The correct option is D. Amino acids (and thus proteins) also have nitrogen atoms; thus, the radioactivity would not distinguish between DNA and proteins.
Explanation:
Nitrogen is an active constituent of amino acids which make up proteins. Nitrogen is also an active constituent of the nitrogenous bases which make up an organism's DNA.
Phosphorus is actively present in the DNA but amino acids lack phosphorus.
Our body is actively made up of DNA and proteins. If the nitrogen was radioactively labelled, the experimental results would be wrong as proteins also have nitrogen in them.
Answer:
Spontaneous repair of peripheral nerves is made possible by Schwann cells, which surround the nerve fibers with an insulating layer, myelin. This fatty layer protects the nerves and increases the speed of transmission of nerve impulses.
Explanation:
Schwann cells are small elements that are created in order to form a layer around the axon of the nerves of the peripheral system. These cells surround the axon by an extensive layer of myelin that is discontinued by the presence of Ranvier's node. Myelin is a single cell organelle, a modified extension of the plasma membrane of the Schwann cell in the peripheral nerve. Its elaboration depends on the regulated expression of a set of genes in the myelinating glia, for which the Schwann cells require axonal contact, as well as to maintain the expression of these genes. Myelin acts as an electrical insulator that facilitates the conduction of the nerve impulse, it helps when the axons must regenerate, that is, when there is some injury or disease that prevents cell transmission. The goal is to help the nerve regenerate and grow again to reach the target tissues. Once the nerve is repaired, the cell regains its ability to produce myelin to cover the nerve with the insulating layer and allow the correct transmission of nerve impulses.
<span>Flowering plants (angiosperms) have a more reliable method of pollination than gymnosperms. Flowering plants use animals and insects while gymnosperms rely on wind for pollination. </span>
