Answer:
What can be noticed about the ligands and their receptor is that the configuration of both coincide, as a key would with its lock, which demonstrates the specificity of a receptor by its ligand.
Explanation:
A <u>ligand</u> corresponds to a molecule considered a signal or a messenger, while the <u>receptor</u> is a protein on the cell surface, with the capacity to accept a ligand.
Ligands and receptors constitute pairs that complement each other, so that <u>each receptor can bind to a specific ligand</u>, similar to what happens with a key and a lock.
Once the ligand-receptor complex is formed, changes occur inside the cell, which define a certain effect.
Answer:
a. 50%
Explanation:
<em>BRCA1 genes is a tumor supressor gene whose harmful mutation can cause hereditary breast ovarian cancer syndrome in both males and females. The BRCA actually stands for breast cancer.</em>
<em>Mutation in BRCA1 gene is heritable and every progeny of a carrier parent irrespective of the sex has a 50% chance of inheriting the trait from such parent, be it from the mother or the father.</em>
Hence, the correct option is a.
The skull is designed to protect the brain.
Answer:
c) repeat the cell cycle continuously
Explanation:
Cell division is a normal phenomenon for all cells as this is the way the cell reproduces and gets repaired in living organisms. However, some cells, due to mutation, keeps dividing and proliferating to form tumours. These cells are called CANCER cells. A normal cell undergoes cellular repair at certain checkpoints of the cell cycle. The checkpoints are necessary to determine a faulty cell and stop its division.
However, cancerous cells do not undergo any repair, which is why they do not enter the G0 phase as mentioned in the question. They keep on dividing out of control without death by repeating the cell cycle continuously.
Explanation:
The division comprises a tremendous diversity of plants among its four subgroups: psilopsids, leafless and rootless primitive forms commonly known as whisk ferns (though not true ferns); sphenopsids, feathery leaved plants commonly called horsetails; lycopsids, low-lying plants called club mosses; and pteropsids,