Answer:
D. as an arrangement of four chemical bases
Explanation:
Our DNA is made up of 4 chemical bases (adenine, thymine, guanine, cytosine).
Answer:
O silicon (Si)
Explanation:
-Valence electrons are electrons of the outermost shell which can participate in chemical bonding. ... -As in silicon, four electrons are present in the outermost shell, so silicon has Four valence electrons.
Answer:
sympathetic stimulation
Explanation:
Under stress or emergency conditions, the preganglionic neurons of the sympathetic division release acetylcholine. Acetylcholine stimulates secretion and release of epinephrine and norepinephrine from the adrenal medulla. These hormones enhance the effects of the sympathetic division of the autonomic nervous system (ANS) during stress. Epinephrine and norepinephrine augment the fight-or-flight response as they increase the heart rate and force of contraction, the output of the heart, and blood pressure. They also increase blood supply to the heart, liver, and adipose tissue. The airways to lungs become dilated and there are increase blood levels of glucose and fatty acids.
Answer:
Lysosomes
Explanation:
Salivary glands are secretory cells. Therefore, they have a very well-developed secretory system.
Lysosomes store secretory proteins and are important for keeping them sequestered from the rest of the cell, and eventually delivering them outside the cell.
<h3><em><u>C.</u></em><em><u> </u></em><em><u>This cell has no nucleus.</u></em></h3>
Because bacterial cell do not have a well-defined nuclear membrane. The coiled DNA particles lie naked in the cytoplasm. This is called nucleoid. While in animal cells the nucleus is surrounded by a well-defined nuclear membrane.