I think the answer is b as in boy.
Answer:
The correct answer would be the virus envelope.
Viral envelope is a protective covering present around the capsid proteins in some viruses.
It is usually derived from the cell membrane of the host and thus it is composed of lipid and viral proteins.
It provides stability to the viral particle, helps in protecting the viral genome, and aids in the fusion of the virus with the membrane of the host.
Examples of viruses in which envelope is present: herpesviruses, poxviruses, flavivirus, hepatitis D et cetera.
Examples of viruses in which envelope is absent: adenoviridae
, papillomaviridae
, picornaviridae
, caliciviridae et cetera.
Answer:
chromosomes is the answer
Answer:
DNA polymerases
Explanation:
The formation of a phosphodiester bond between adjacent nucleotides is catalyzed by the DNA polymerases. They do this efficiently only if the incoming base on the incoming nucleoside triphosphate is complementary to the base on the template strand and can bind efficiently.
Answer:
Blood Brain Barrier(BBB)
Explanation:
This is a biological interface of special endothelial cells of astrocytes, pericytes , capillaries, neurons and other structures, acting as a physical barrier or gate separating the Central Nervous system from the peripheral blood circulations. Thus it formed a tight junction serving as a physical barrier to selectively regulate the entrance of substances from the cerebral blood flow into the brain, therefore maintaining homeostasis of the brain.
From above any substances absorbed into the blood stream irrespective of the mode of entry are transported through the BBB, and are selectively regulated to enter the brain cells by the BBB's interactions with the blood vessels, hormones etc.
Basically it allows the passage of nutrients, a few drug, hormones and resists certain toxins and pathogens for the brain homeostasis.
