The correct answer is option (d) They allow the exchange of gases between cells in the leaf and the external environment.
Stomata are the tiny openings present in the epidermis (outer layer of cells) of the leaf. They have a pore which is guarded by the guard cells which controls the opening and closing of the stomata. Air enters and exits through the stomata.
The main funtion of stomata is to facilitate the gaseous exchange. The gas exchange that occurs when the stomata are open helps in the process of photosynthesis. During photosynthesis, carbon dioxide is taken in from the atmosphere and oxygen is released as a by-product of photosynthesis. The glucose produced is converted into the starch and stored in the leaves.
Also, water vapour diffuses through the stomata into the atmosphere by a process called the transpiration.
Thus, stomata are the structures that are mainly involved in the gaseous exchange between the cells of the leaf and the atmosphere.
Answer:
Option (4).
Explanation:
Cell membrane potential may be defined as the difference in the electric potential between inside and outside of the cell. This potential is important for the action potential.
The resting membrane potential of the cell is -70mV. This membrane potential is maintained by the potassium ions of the cell. The cell membrane are almost 40 times more permeable to potassium ions than sodium ions and makes the cell membrane potential negative.
Thus, the correct answer is option (4).
Answer:
It contains Uracil (U) instead of Thymine (T).
Reason for primer removal:
This is because of their uracil nucleotide which is absent in DNA. Instead of Uracil DNA contains Thymine nucleotide.
Explanation:
Primers:
Primers are a short sequence of RNA. These sequences attached to the 5' end are the requirement of DNA polymerase to start the process of replication.
Primer removal:
After replication, these short fragments of RNA are removed to replaced with DNA from the newly synthesized DNA strand.
Reason for primer removal:
This is because of their uracil nucleotide which is absent in DNA. Instead of Uracil DNA contains Thymine nucleotide.
Best Answer:
Because It contains Uracil (U) instead of Thymine (T).
<span> One reason farmers often choose GM crops over non-GM crops is because GM crops are able to produce more yield. When farmers use GM crops, there are many benefits that they could gain. It has been proven that GM crops are more resistant to pests, and other harmful substances, which also reduce the costs for pesticides and crop-maintenance. Since GM crops are more resistant to harmful substances, more of them can be used by farmers.</span>
