Develop from a single fertilized egg and have identical genes.
Answer:
a) DNA fragments associated with histone proteins are all multiple in length (i.e., 260 bp, 520 bp, 780 bp, etc), thereby suggesting the presence of a pattern of organization in the chromatin
b) it suggests that each unit of organization (ie, each nucleosome) consists of 260 bp associated with chromatin proteins
Explanation:
The nucleosome is considered as the basic unit of chromatin. A nucleosome consists of approximately two turns of DNA wrapped around a core of eight histone proteins (i.e., a histone octamer). The histone octamer consists of two copies of each of the histones H2A, H2B, H3, and H4. Moreover, the nucleosomes are connected together by linker DNA sequences which vary between 10 and 100 bp in length.
The answer is diffusion.
The most important mechanism that enables oxygen and carbon dioxide (but as well other small molecules such as glucose, amino acids, wastes) across capillary walls is diffusion. Diffusion is a net movement of molecules through some barrier from an area of high concentration to the area of low concentration. When blood rich in oxygen reaches capillaries close to the cell, now there <span>is </span>more oxygen in the capillaries than in the cells and by diffusion, oxygen will pass capillary walls and enter the cell. Since blood in capillaries lacks in carbon dioxide, it will easily leave the cells and enter the blood. It should be taken into consideration that capillary walls may be fenestrated, continuous, and discontinuous which can affect movement through them.
