Answer: a). AA
Explanation: Every trait is controlled by at least a pair of gene. Genes have different forms known as alleles. Alleles can be dominant or recessive. A dominant allele expresses itself in the presence of a recessive allele and masks the effect of a recessive allele. A recessive allele cannot express itself in the presence of a dominant allele and it's effect is masked by a dominant allele. Dominant alleles are usually written in upper cases such as A, T, while recessive alleles are usually written in lower cases such as a, t. The two alleles that determines a trait is called a genotype. A genotype can be homozygous if the two alleles are identical such as in AA or aa
and can be heterozygous if the two alleles are not identical such as in Aa, Tt.
Essentially the answer is in the names. Active transport requires energy to facilitate to movement of the materials while passive transport is something like osmosis which is when the material moves based on concentration in an effort to create equality between the two sides. Basically passive is when the materials move under the own power.
Answer:
Base substitution mutation
Explanation:
Mutation is the alteration or change that occurs to the sequence of a gene caused by a mutagen (chemicals) or spontaneously-induced. Depending on how the mutation occurs, it is of different types. The mutation shown in this question is as follows:
ATCGGCTTAACG to ATCGGCTAAACG
This type of mutation is called SUBSTITUTION MUTATION. Substitution mutation is a type of mutation that involves the replacement of one or more nucleotide base by another. In this original sequence; ATCGGCTTAACG, the eight base T was replaced by base A in the sequence, hence, it is a substitution mutation.
Answer:
Option (e).
Explanation:
Meiosis may be defined as the process of cell division in which a single parent cell divides into four daughter cells. The chromosome number reduces to half in meiosis.
Crossing over is the process of exchange of genetic material between the homologous chromosomes of the non-sister chromatids. Crossing over will bring variation in the gametes. Hence, the absence of crossing over results in the formation of gametes with less genetic variation.
Thus, the correct answer is option (e).
The reason for why celery stalk firms in water is because of its hypotonic environment and the salt content transfers into the celery stalk which makes the cell firm and significantly bigger.
