The story between the two pairs of scientists, Watson and Crick, who discovered just one of "the most important molecule in the history" is a series of ups and downs. They are an unlikely pair and they had difficulty in unraveling the molecule because neither are that much knowledgeable on structural chemistry.
Protoplasm is the organic substance making up the cell of all living things
Answer:
All of these choices are correct.
Explanation:
Cell cycle is the process of growth and division of cell. It comprises of interphase and mitosis. In interphase the cell grows, replicates its genomic content and prepares itself for division. In mitosis the division occurs.
Cell cycle is controlled by a group of kinases called as Cyclin dependent Kinases (CDKs). They act by phosphorylating their substrates. They are of various types like Cdk1, Cdk2, Cdk4 etc. They become active when they bind to a regulatory protein called cyclin. They are also of various types like Cyclin A, Cyclin B, Cyclin C etc. Level of cyclin and corresponding CDK increases and decreases according to the stage of cell cycle. For example in S phase of cell cycle concentration of cyclin A and E shoots up. CDK2 is able to bind to these cyclin molecules and hence it becomes active.
Cell cycle has major checkpoints where the condition of cell is analysed before it proceeds to the next stage of cycle. If any abnormality is detected, repair mechanism is activated or the cell is killed. Checkpoints do not allow cell cycle to proceed in damaged cells.
p53 is a tumor suppressor protein which can halt cell cycle when it detects some abnormality in cell. It usually acts in G1/S checkpoint (before the DNA replication starts in cell) and G2/M checkpoint (before the cell division begins). Hence, all of the above statements are true.
As their contents are used for energy during weight loss, fat cells get smaller in size, but their overall number doesn't change.
<h3>Where Does Fat Go When Weight Is Lost?</h3>
- Fats are liberated from fat cells and transferred to the mitochondria, the energy-producing organelles in your body's cells, by sustaining a steady calorie deficit. Here, a number of procedures break down the fat to create energy.
- These same cells may become smaller when you lose fat, yet they continue to exist in roughly the same numbers. Therefore, fewer fat cells, not more, are the main cause of changes in body form.
- Also implied by this is that even when you lose weight, fat cells are still present and can readily regain their original size if efforts are not made to keep the weight off.
To learn more about Weight loss refer to:
brainly.com/question/12688339
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