Which type of immune response involves direct contact t cells and antigens?

Identifying and destroying harmful substances

Explanation:

The three phases of immunity titled are: recognition, attack, and memory. A helpful mnemonic, for this will be to RAM, the pathogen out of the body. The initial step of recognition signals to the body is a foreign pathogen, stimulating an immune response.

sexual reproduction produces offspring with novel combinations of genes. species that reproduce sexually must maintain two different types of individuals, males and females, which can limit the ability to colonize new habitats as both sexes must be present.

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