Answer:
Mutation
Explanation:
In genetics, any heritable change of the base-pair sequence of genetic material is referred to as MUTATION.
SIV (Simian Immunodeficiency Virus) must have undergone mutation, which is the basis of genetic variation or evolution
Answer: The SA node
Answer choices are:
<span>A. </span>The AV node
<span>B. </span>The SA node
<span>C. </span>The purkinje fibers
<span>D. </span>The AV bundle
The SA node<span> is the heart's natural pacemaker consisting of a cluster of cells located in the upper part of the wall of the right atrium. (the right upper chamber of the heart). The electrical impulses are produced and sent out from there to regulate heartbeat. This is also called the sinus code. </span>
Answer:
B !
Explanation:
I'm basing this off of a lesson I took two years ago, but the answer is B! The interior of Earth is rumored to be filled with magma as a way to have convection currents in itself, and to move the tectonic plates/ create the tectonic plates, if I remember correctly.
If i'm wrong I can still prove why it's not the other choices.
It's not A becuase when rock gets hotter, it rises, and when it cools, it sinks.
it's not C becuase it said "interior of the planet", which it may be referencing somewhere having to do to below the crust. as well, you need to cool rocks as to make it solid, not heated up rocks. but even then, mountains are made by the plates.
it's not D becuase glaciers are affected by climate change and occurrences the biosphere, not the interior of the planet.
Answer: the insertion of a nucleotide into DNA
Explanation:
1) I think letter a, indicates the systolic pressure which is at the peak of changes in blood pressure. Systolic pressure refers to the amount of pressure in the arteries during contraction of the heart muscles. If the measurement reads 120 systolic and 80 diastolic, one would say "120 over 80" or write "120/80 mmHg which is the normal pressure.
2) i think letter b, represents diastolic pressure; where there is a dip in the changes in blood pressure. Diastolic blood pressure measures the pressure in blood vessels when the heart rests between beats. It therefore, refers to the blood pressure when the heart muscle is between beats.
3) I believe letter d, indicates arteries, When blood enters the arteries from the aorta, both pressure and velocity begin to fall. As blood leaves the arteries and flows through the arterioles, both pressure and velocity drop rapidly. Arteries deliver oxygen rich blood from the heart to the tissues of the body. Each artery is a muscular tube lined by smooth tissue and are made of three layers.
4) I think the letter that indicates the venules is g, Cappillaries to venules to veins to venacava and to the heart. Venules are small blood vessels in the microcirculation that allows blood to return from the capillary beds to drain into the larger blood vessels veins.
5) I believe letter i indicates vessels in which blood pressure is the lowest; Cross section increases thus causing a decrease in velocity thus reducing the blood pressure. Blood pressure is lowest in the veins as the blood is returning to the heart.
6) i believe letter f indicates the vessel in which blood travels the most slowly. Velocity of the blood is the lowest in the capillaries approximately 500 times more slowly than the Aorta. Capillaries are the smallest blood vessels. They serve to distribute oxygenated blood from arteries to the tissues of the body and to feed deoxygenated blood from the tissues back into veins.
7) I think letter h, indicates the vessels in which blood velocity is increasing the most. The velocity of blood increases the most from the capillary to the veins. Blood pressure is highest in the aorta as blood is ejected from the left ventricle. Blood pressure gradually decreases from the aorta to the large arteries to arterioles, to capillaries, then finally lowest in the veins before returning to the heart.
