Answer:
The environmental factor that could lead to a decrease in genetic variation in a tuna population is an increase in pollution (second option).
Explanation:
There is a correlation between genetic variability and environmental pollution, the latter being a factor that impacts negatively on the variability of a specific population.
The concept of pollution stress not only implies a low rate of reproduction, but it is also a factor that prevents genetic exchange with other populations, which is a factor that makes the genetic variability decrease in a population.
For these reasons an increase in pollution implies a decrease in genetic variability in a tuna population.
- <em>Other options, such as </em><u><em>an increase in food availability</em></u><em>, a</em><u><em> decrease in tuna fishing
</em></u><em> or </em><u><em>a decrease in tuna predators</em></u><em>, are environmental factors that contribute to increased genetic variability.</em>
Answer:
The number of primary consumers will increase
Explanation:
If all the secondary consumers disappear, the primary consumers will continue to reproduce causing the population to increase
The right answer is The cells are damaged.
Take the example of skin cells.
The skin consists of two tissues:
* the outermost, the epidermis, resting on a vascularized connective tissue,
* the dermis.
In the epidermis, which includes several layers of cells, the outer layer is formed of dead cells that are desquamating and are constantly being replaced from proliferating basal cell cells. So, in normal conditions, the epidermis is in constant renewal.
On the other hand, when accidentally, the upper parts of the epidermis are damaged, for example, a slight abrasion or of a burn, the destroyed portion is regenerated (replaced) thanks to an accelerated proliferation of basal epidermal cells .
Answer:
1. The difference between the normal hemoglobin protein DNA sequence and the sickle cell hemoglobin DNA sequence is a base to base shift, in this case adenine (GAG) to thymine (GTG).
2. The difference affects the amino acid sequence of the protein by replacing glutamic acid (Glu) with valine (Val).
Explanation:
In sickle cell anemia, a change in the DNA nucleotide sequence is observed, where adenine is substituted by thymine, whose expression is the change in the amino acid sequence of globine β, incorporating valine instead of glutamic acid. This represents a molecular mutation - point mutation - by subtitution, which corresponds to missense mutation.
<u>Normal hemoglobin protein in a RBC</u>
DNA CTG ACT CCT GAG GAG AAG TCT
Amino acids Leu Thr Pro Glu Glu Lys Ser
<u>Sickle cell hemoglobin protein in a RBC</u>
DNA CTG ACT CCT <em>GTG</em> GAG AAG TCT
Amino acids Leu Thr Pro <em>Val</em> Glu Lys Ser
When GAG is transcribed to mRNA, the CUC codon is obtained, which codes for glutamic acid. Thymine substitution causes the DNA sequence to change to GTG, which is transcribed as CAC, the codon that encodes the amino acid valine. The <u>change from glutamic acid to valine in β-globin causes an altered hemoglobin, giving the abnormal erythrocytes observed in sickle cell disease</u>.
The best description about the brain stem is: it is the most important organ of our body's survival. It connects the brain and the spinal cord, controls the vital organs like the lungs and heart and it also coordinates the many essential body reflexes.