Answer:
many alveoli are present in the lungs with a shape that further increases surface area. Thin walls - alveolar walls are one cell thick providing gases with a short diffusion distance. Moist walls - gases dissolve in the moisture helping them to pass across the gas exchange surface.
Explanation:
An immunoglobulin molecule of any class with regions symbolized as C or V, H or L, has a light chain made up of one C region and one V region.
The glycoproteins known as immunoglobulins (Ig), often known as antibodies, are created by plasma cells. A number of immunogens, including bacterial proteins, promote B cells' conversion to plasma cells. These cells, which make proteins, are involved in humoral immune reactions to bacteria, viruses, fungi, parasites, cellular antigens, chemicals, and synthetic compounds. Using a B-cell receptor, the immunogen or antigen adheres to the B cells' cell surface (BCR).
As a result, a signal is generated that directs the activation of transcription factors, leading to the manufacture of highly specific antibodies for the immunogen that initially activated the B cell. Furthermore, one B cell clone produces immunoglobulin (specificity). Two light chains and two heavy chains that alternate in a light-heavy-heavy-light pattern make up antibodies, also known as immunoglobulins. Therefore, choice A is the right response.
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Answer:
Index fossils
Explanation:
The index fossils are the fossils that come in very handy for the geologists when it comes to identifying or dating rock samples or other fossils. The reason for this is that the index fossils have already been dated. They are fossils that are very commonly found, wide dispersed, are easy to be identified, and are limited to only a certain geological period. These characteristics make them an excellent indicator for the dating of the rock layers in which they are found, or the fossils found in the same layers with them, without conducting further examinations.
The answer is C) selective breeding. This means that humans are deciding what to breed which means this is not a natural selection, but rather an artificial selection.
