Answer:
The process whereby organisms better adapted to their environment tend to survive and produce more offspring. The theory of its action was first fully expounded by Charles Darwin, and it is now regarded as be the main process that brings about evolution.
Four conditions are needed for natural selection to occur: reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population. If they are met, natural selection automatically results.
Answer:
1. Iterative homology: e.g. antenna and leg of fiddler crab
2. Ontogenetic homology: e.g. radular teeth of veliger, feathers of chicken and hen
3. Di-polymorphic homology: e.g. white and brown feathers of hen races, chelae of male and female of fiddler crabs
4. Supraspecific: e.g. chelae of fiddler crab, chelae of lobster, feathers of hen and pheasant
Explanation:
One of the primary functions of rna molecules is to function in the synthesis of proteins.
Answer:
these statements are true
B) Insertions or deletions of single base-pairs within a protein coding sequence probably change the amino acid sequence
D) Missense mutations always change the amino acid sequence encoded by a gene
E) Nucleotide substitutions outside of the coding sequence can affect the expression of a gene.
Explanation:
B) insertion or deletion of nucleotide in coding region of DNA can change the amino acid sequence encoded.
D) missense mutation means that the change in nucleotide sequence resulting in change in amino acid sequence encoded by gene.
E) A mutation may alter the promoter of a gene, thereby affecting the rate of transcription.