Answer:
False
Explanation:
The papillary muscles of both right and left ventricles began to contract shortly before the other ventricular muscles (systole) so that they can take up the slack on the chordae tendineae as the full force of ventricular contractions sends blood against the atrioventricular (AV) valve flaps.
They prevent the backward flow of blood to atria from ventricles. So if they contract after the ventricle systole they would not be able to perform their job.
The structure is calcium ions.
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.
Answer:
Occurrence. In primary succession pioneer species like lichen, algae and fungi as well as other abiotic factors like wind and water start to "normalize" the habitat. Primary succession begins on rock formations, such as volcanoes or mountains, or in a place with no organisms or soil.
Explanation: