Answer:
B. Many members of a key species, and the ecosystem will no longer be stable.
Explanation:
An ecosystem that contains a high degree of biodiversity will have numerous organisms of different species. According to the question, sharks are stated to feed on a wide variety of prey. This means that sharks can feed on any other species of organisms at lower trophic levels.
In a situation whereby an ecosystem contains a low degree of biodiversity i.e. low variety of species, the sharks will have to consume a large numbers of a key species, which will cause the ecosystem to lose stability.
<span>The cell that dominates the deep cortical region of a lymph node is the T cell.</span>
Answer:
Adenine= 22%
Guanine= 28%
Cytosine = 28%
Explanation:
According to Chargaff rule, the amount of adenine in a double-stranded DNA is equal to the amount of thymine. This is due to the fact that adenine and thymine bases are complementary and form base pairs.
Likewise, the amount of guanine in a double-stranded DNA is equal to the amount of cytosine since guanine pairs with cytosine.
Given that percentage of thymine in a DNA sample = 22%
Percentage of adenine = 22%
Total percentage of adenine and thymine = 22+ 22 = 44%
Percentage total of guanine and cytosine bases = 100-44 = 56%
Percentage of guanine base in the DNA = 56 /2 = 28%
Percentage of cytosine base in the DNA = 28%
Answer:
b. phospholipid bilayer of membrane
Explanation:
The phospholipid bilayer evidently has in its structure mainly phospholipids, alcohol compounds and fatty acids.
Each molecule in the membrane phospholipid bilayer has two heads and a tail, both heads being hydrophilic (having affinity for water) and the tail being hydrophobic (having no affinity for water, and therefore repelling it).
This structure, with the heads, which are hydrophilic facing the intracellular and extracellular environments of cells, thus prevents the passage of polar compounds.
