Answer:
DNA is made of chains of four smaller molecules called "Nucleotides".
Explanation:
A molecule consisting of a nitrogen-containing base (adenine, guanine, thymine, or cytosine) in DNA is known as a nucleotides.
Trisomy 21, as illustrated by the karyotype, is caused by nondisjunction. This occurs when chromosomes do not separate properly during meiosis.
Answer is D) nondisjunction
Answer: They help control what enters and leaves the cell.
Explanation: carbohydrates also help the immune system identify if the cell is foreign or not.
Answer:
The correct answer is option a, that is, sympatric speciation.
Explanation:
Speciation, which takes place when two groups of similar species live in a similar geographical location, however, they evolve distinctly unless and until they no longer interbreed and are regarded as different species is termed as sympatric speciation.
Sympatric speciation is not similar to other kinds of speciation, in which the formation of a new species takes place when a population gets differentiated into two groups because of migration or geographic barrier. The sympatric speciation can be witnessed in various distinct kinds of species. Thus, the given case of monkeys is an illustration of sympatric speciation.
Correct answer: B). The phagocytotic barrier, which is a part of innate immunity
The scenario represents the phagocytosis, which is a type of endocytosis by which the cell engulfs microbial pathogens. The main cells of the immune system that are involved in phagocytosis include macrophages, neutrophils, and dendric cells.
It is a mechanism which is used by the immune system to kill and processing of antigen that play an important role in innate immune response.
Hence, the correct answer would be option B.