Amoeba acquires it food by endocytosis, that is, a small region in the plasma membrane which ultimately forms a intra-cellular membrane-bound vescicle. It engulfs it food using its pseudopodia (temporary protrusion of the surface of the amoeboid cell used for feeding and movement) and forms a vacuole around it. When the food is already trapped inside, it releases a digestive enzyme to digest it. Intake of liquid particles is pinocytosis (cell drinking) while intake of solid particles is phagocytosis (cell eating).
Answer:
(1) roots, (2) stems, (3) leaves, and (4) flowers
Explanation:
Answer:
The fewer number of T cells a person has, the more chances to be affected by an opportunistic infection. When the number of T cells reaches 200 cells/µl, the person is at risk of being infected by other infections.
Explanation:
The whole immune system of a person who is infected with HIV infection seems to be severely affected. When the person is not treated or the disease is in a very advanced stage, the depletion of the T- cells turns to be very sharped, especially CD4+ T cells. At this point, the immune system can not resist the attack of other microorganisms. The <em>lower is the number of CD4+ T Cells, the higher possibility the person has to be attacked by opportunistic infections. </em>
Classically, it has been suggested that opportunistic infections appear after the CD4 + T lymphocytes reach very low levels, such as 200 cells/µl. The number of circulating T cells can be used as an indicator and a measure of global "immune competence", and the previously mentioned amount of CD4 + T cells is an accepted universal reference used to predict the risk of having one of these opportunistic infections.
Answer:
A. The tails do not interact with the DNA
Explanation:
The acetylation refers to the transfer of the acetyl group from Acetyl-CoA to the N-terminal of the histone protein.
Lysine residues (positively charged amino acid) are present at the end of the N-terminal of the histone protein which is neutralized by the acetyl group.
This loses the compaction between the positively charged histone and the negatively charged DNA and the DNA becomes more relaxed. This relaxed state allows the transcription factors to easily bind the DNA and therefore the DNA becomes transcriptionally active.
Thus, Option-A is correct
A federal government is the type of government that combines aspects of both unitary and confederal government. The United States has a federal government.
