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:
1. Earth's ozone layer is responsible for absorbing infrared and ultraviolet rays from the sun.
2. Changes in the composition of the atmosphere have caused gradual changes in earth's climate, causing changes in plant and animal life that contributed to mass extinctions.
3. Chemical chlorofluorocarbons (CFCs) have been banned and replaced with hydrochlorofluorocarbons (HCFCs).
4. Naturally occurring volcanic eruptions can produce large amounts of gases which contain sulfur. These gases accumulate in the atmosphere in the same way as man-made sulphuroxides.
Sorry, but after that I don't know.
Explanation:
Answer:
Well the only organelle that produces ATP/cellular energy is the mitochondria so via process of elimination you would conclude mitochondria are most abundant in muscle cells.
Answer:
92.
Explanation:
92 chromatids are visible for humans at prophase stage because the replication of 46 chromosomes occur. When the replication of chromosomes occur, each chromosome is converted into two chromatids so when 46 chromosomes replication occur then it changed into 92 chromatids. So we can say that there is 92 chromatids in humans in the prophase stage of mitosis.
