Answer:
Q3:False, the oldest layers are found in the lower layers
Q2: A, a layer or a series of layers of rock in the ground
Q5: D
Q4: possibly D
Explanation:
Polymerase chain reaction to amplify the DNA would be the technique used in the blood lab.
Answer:
Friction make stuff go the opposite way sot the ball wound go to the left bc of fiction and the ball would go to the right for motion
Explanation:
Answer:
The membrane potential of a nerve cell will depolarize if there is an increase in the positive ions inside the cell.
Explanation:
When nerves are in resting potential it is -70mV. In this stage interior of the cell is negatively charged and outside is more positive. When depolarization occurs the inside cell becomes positive.
This is due to the rush of sodium ions into the cell by voltage-gated channels. Now the inside charge is more positive and the chloride ions move out of the cell. Thus outside becomes more negative.
After some time of depolarization stage, potassium ions move out of the cell making the nerve cell again negative. Now the depolarized stage becomes repolarized by the entry of potassium ions.
During depolarization, the potential of the cell is -55mV. When repolarization occurs, it is again -70mV. But the potassium channels are open and some of the potassium ions move out of the cell making the inside environment more negative. This is known as hyperpolarization condition.
This hyperpolarization remains for a short period where action potential can't occur. This period is called the refractory period. Again potassium ions enter into the cell. This results in the resting potential of the neuron again.
Answer:
Endonucleases
Explanation:
<em>Endonucleases are involved in DNA repair. The repair can be a base-excision repair, nucleotide excision repair or mismatch repair.</em>
Endonucleases are of different types and the type that will involve in DNA repaid depends on the type of repair that is required. It include deoxyribonuclease I and restriction endonuclease/restriction enzymes. The former cleaves DNA without taking note of the nucleotide sequence while the later is specific in the sequence of nucleotides it cuts.