Answer: Substances that are protein based cannot cross the lipid cell membrane, but can exert their effect by binding to the proteins based receptors present on the lipid bilayer.
Explanation:
Hormones such as calcitonin , Parathyroid hormone and pituatry horomones are proteins and water soluble.They cannot cross lipid bilayer but can bind to ligand binding protein receptors.
These receptors are protein macromolecules that are specific in nature for specific hormones.
After binding to the receptors, these hormone-recpetor complexes activate second messengers and regulate the downstream effects.
Answer:
D
Explanation:
I got it wrong and it showed the answer :))) hope it helps
The answer is B
Here is a small experiment you can do to test this.
<span>
Put a pot of water on the stove and bring it to a boil. Take a dry lid and cover it for a minute, and lift the lid up. What happens?
What should happen is that the water droplets run down the lid and fall back into the pot.</span>
Answer:
C
Explanation:
The damage to DNA usually occurs where there are two consecutive thymine nucleotides on a DNA strand. The energy from the UV light causes the two dimers to form a cyclobutane pyrimidine structure. Proofreading and repair mechanism of DNA find it difficult to repair this kind of damage on DNA. During replication, therefore, DNA polymerase is unable to replicate this region hence leading to a mutation on the replicated strand at this local point.
