Answer:
D
Explanation:
Hormones are bigger than the cell pores hence cannot pass through the cell membrane to influence biochemical processes. Therefore, hormones (such as glucagon and insulin) bind onto receptors on the cell membrane, then transmembrane proteins, such as the G-protein, change conformation activating the secondary messengers inside of the cell. Cyclic- AMP is a major secondary messenger significant in activating protein kinases.
Answer:
Genetic diversity is important because it allows organisms to adapt to changes around it, thereby preventing extinction- <u><em>True</em></u>
Explanation:
Genetic diversity is one of the main reasons that brings about the survival of an organism in an ecosystem. As alleles of a gene assort independently during gamete formation, this phenomenon brings about genetic diversity. The genetic diversity allows organisms with better traits to survive and hence, they become better adapted to live in a habitat. As the organisms with better traits survive, extinction of species becomes lesser through this phenomenon.
<span>The head of the sperm contains the necessary enzymes to help it penetrate the oocyte. The sperm cell is anatomically structured to have four parts which are the head, neck, midpiece, and a tail. Inside the head of the sperm are densely coiled chromatin fibers that contain the nucleus for helping the sperm penetrate the female fertilized egg necessary for reproduction.</span>
Answer:
If a DNA strand has the base sequence TTCCGGAA the complementary strand has the sequence AAGGCCTT.
Explanation:
A DNA molecule is constructed from sequences of its four nitrogenous bases: adenine, thymine, guanine and cytosine. Since DNA is made up of two strands, the sequence of nitrogenous bases of one strand is complementary to the other
.
The complementarity of the bases is a characteristic of the nitrogenous bases in the nucleic acids to combine with their complementary base, which is the same as saying that purines complement with pyramidines.
- <em>Adenine is combined with Thymine A=T
</em>
- <em>Cytosine is complemented with Guanina C≡G
</em>
In this way, given a sequence on a DNA strand
:
<em> T-T-C-C-G-G-A-A</em>
The complementary strand will have this sequence:
<em> A-A-G-G-C-C-T-T</em>
