Answer:B) homologous chromosomes trade pieces of dna
Explanation:
Crossing over occurs between two homologous chromosome of sisters chromatid. Crossing over leads to exchange of genetic material between the two sister chromatids leading to recombination.
Answer:
Genetic code
Explanation:
Genetic code refers to the set of rules by which the information encoded in the genetic material is translated into the proteins. The genetic code is present on the genes in the form of triplets of nucleotides called codons which specifies the specific amino acid.
The codon system of the genetic code rules allows the 4 different nucleotides to form specific amino acids by the combination of the four different nucleotide in the triplets.
Thus, Genetic code is the correct answer.
The earth's tilt. The tilt of the Earth on it's axis is what makes the sun heat up different parts of the Earth at different times, thus making wind, thus making different weather patterns. Depending on how much sun (heat) the area is getting, it changes the weather.
Answer: By Hormonal action and Nervous coordination
Explanation:
Hormones are substances produced by one tissue and conveyed by the bloodstream to another to effect physiological activity. Homeostasis is the maintenance of a stable internal environment in the body.
Body systems such as digestive, circulatory, excretory systems etc, all are coordinated to achieve a STABLE INTERNAL ENVIRONMENT by the aid of HORMONES AND/OR NERVOUS COORDINATION.
For Example: the vasodilation of blood vessels during hot weather, and the opposite action of vasoconstriction during cold weather are both controlled by Hormonal action and nervous coordination which leads to a stable body temperature preventing excess heat accumulation.
Also, Nervous system controls the body systems, such that the muscle contractions are joined to actions like sweating, breathing, respiration etc
So, to maintain homeostasis hormonal action and Nervous coordination is necessary.