4. which of the following statements correctly describes the role of white blood cells in the human immune system?

a. neutrophils gather at sites of infection and release histamine, while macrophages ingest antigens before they enter the bloodstream.
b. monocytes gather at sites of infection and release histamine, while basophils ingest antigens before they enter the bloodstream.
c. neutrophils gather at sites of infection and release histamine, while monocytes ingest antigens before they enter the bloodstream.
d. basophils gather at sites of infection and release histamine, while macrophages ingest antigens before they enter the bloodstream.

A. Neutrophils gather at the site of infection and release histamin, while macrophages ingest antigens before they enter the bloodstream.

Explanation:

Neutrophils are specialized white blood cells which are capable of fighting against the infections. Neutrophils are required at the site of injury and produces histamin to fight against inflamation. Whereas the macrophages are type of monocytes that ingest foreign antigens or bodies like bacteria and virus which could enter the bloodstream and cause disease oriented symptoms.

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure

check for the pregnancy rating of drug. if its class c or d see if other alternatives