Answer: Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).
By the end of meiosis, the resulting reproductive cells, or gametes, each have 23 genetically unique chromosomes. The overall process of meiosis produces four daughter cells from one single parent cell.
Explanation:
During meiosis, homologous chromosomes (1 from each parent) pair along their lengths. The chromosomes cross over at points called chiasma. At each chiasma, the chromosomes break and rejoin, trading some of their genes. This recombination results in genetic variation.
The propositions are:
a.alkylating agents
b.antimetabolites
c.topisomerase inhibitors
d.nucleoside analogs
e.<span>AZT
The right answer is A,
An alkylating agent is a compound capable of adding alkyl groups to various electronegative groups under conditions present within the cells.
Antimetabolites are an anticancer drug but act differently than the alkylating agent. (interfere with folic acid)
Topoisomerase inhibitor acts by inhibiting isomerase, used in antibiotherapy (like quinolones).
Nucleoside analogs are analogs as their name says, it does not alkylate nucleotides.
AZT (</span><span>Zidovudine) is an antiretroviral drug that inhibits reverse transcriptase.</span>
Yes because plant cell is eukaryotic and it is also in animal cell too.
The answers are A, B, & C. Steroid hormones have a
longer half-life than peptide hormones because steroid hormones ride on carrier
proteins in the blood. In other words, they
are bound to protein carriers that transport molecules across the membrane. They can also be stored temporarily in the adipose
tissue. And also, steroid hormones are sent to the nucleus where it regulates transcription
while peptides don’t require this process. This is the reason why the effects of
steroid hormones are exerted more slowly than peptides.
Answer:
0.1% of energy
Explanation:
Energy flow: From the whole quantity of energy that reaches the earth's surface, autotroph organisms or producers absorb only 0.1 or 1%.
From the input of solar energy begins a unidirectional energy flow through all the organisms in the ecosystem, from autotrophs to heterotrophs, until it is dissipated in the environment.
At each trophic level occurs an energy transfer to the next, with only 10% being usable in each of them. This assessment is called "The 10% rule". As a general rule, only about 10% of the energy stored as biomass at one trophic level, per unit time, ends up as biomass at the next trophic level, in the same unit of time.
If wheat transferred 10% of the energy to mice, and of that 10% mice transferred 10% of the energy to hawk, then the percentage of energy transferred from the first trophic level to the third equals 0.1%.
10% (1st TL-2nd TL) / 10% (2nd TL - 3rd TL) = 0.1% (1stTL - 3rd TL)
<em>TL = Trophic level </em>
