Answer is D cilia are absent in plant cells
Answer:
Explanation:
The switch from glutamic acid to valine in position 6 of hemoglobin (HB) forms the basis of sickle cell anemia disease pathology.
Valine is hydrophobic and it's chain is shorter than glutamic acid. The lack of the carboxylic acid and shortness of valine will result in loss of the ionic interactions formed between the glutamic acid's carboxylic group and other amino acids. A hydrophobic cavity will form in the beta sheet of HB due to the short and hydrophobic structure of valine. For these reasons, the HB molecule will be less stable and insoluble in water. The insolubility is thought to be caused by fibril formation between the valine interacting with hydrophobic pocket residues of the adjacent HB molecule. This would in turn affect binding of oxygen to HB.
Answer:
The answer is Spanish flu
Answer:
Changes in gene expression
Explanation:
This phenomenon is the result of changes in gene expression. That means, how the information in the DNA is used by the cell. The genes that are active in the cells of the brain will be very different from the genes that are active in the cells of the bone marrow.
These patterns of gene expression are different for each cell, and dictate the identity of that cell. Gene expression patterns are controlled by a variety of factors in the cell that allow tissue-specific expression, such a transcription factors.
This can also be facilitated by another layer of regulation called epigenetics, which literally means "on top of" genetics, and refers to modifications of DNA (and the proteins around it), that can reflect and influence the activity of the genes within.
Answer:
both options 4 and 3 is the answer..
