Answer:
Adaptive immune defense system consists of lymphocytes like B-lymphocytes and T- lymphocytes. B-lymphocytes provides humoral immunity while T- lymphocytes provide cell-mediated immunity to the body.
99% of lymphocytes circulate freely in the blood and lymph. B lymphocytes differentiate into plasma B cells and B memory cells when interact with antigen presented by T helper cells.
Then plasma cells secrete antibodies in the circulation which binds to extracellular antigens through antigen-binding site. Then the bounded antigen is recognized by receptors present on phagocytic cells. This receptor binds the Fc region of antigen bounded antibody and destroy the antigen by phagocytosis.
Answer;
-Stratosphere
The Stratosphere is responsible for absorbing the most UV radiation.
Explanation;
-The stratosphere is the second layer of the atmosphere as you go upward lying between the troposphere and the mesosphere.
-The stratosphere layer also called the ozonic atmospheric envelope, is important to human's life as it contains the ozone layer which absorbs the harmful ultraviolet radiations which emitted from the Sun , and also it is convenient for flying of the planes .
I think the answer is B,A,E
Answer:
prokaryotic are unicellular organisms
eukaryotic are multicellular
Prokaryotic need only one parent to reproduce
Eukaryotic need 2 parents to reproduce
Explanation:
<span>The scientific view's order of Earth's first living things to the most recent is described by choice C. cyanobacteria, hagfish, crocodilians, giant ground sloths. Cyanobacteria have lived on the Earth since the Precambrian supereon. Actually, they first appeared in the Archean eon (4-2.5 billion years ago). Hagfish, as other jawless fish, appeared in the Paleozoic era (541-252 million years ago). Crocodilians appeared in the Cretaceous period (145-66 million years ago). Giant ground sloths, also known as megatherium, appeared in the Pliocene epoch (5.33-2.58 million years ago).</span>
