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.
Answer:
Option 1, a charged end and a noncharged end
Explanation:
Complete question
If a small droplet of ordinary fat is suspended in water, the fat molecules form a "ball of spaghetti" with no particular orientation. But if a droplet of phospholipid molecules is put in water, all the molecules point outward, toward the water. Phospholipids are forced into this orientation because phospholipids have _____
- a charged end and a noncharged end
- three fatty acid molecules, all pointing in different directions
- two fatty acid molecules pointing in different directions
- both a saturated fatty acid and an unsaturated fatty acid
- two charged ends
Solution
The structure of phospholipids consists of the following groups and molecules –
a) A glycerol molecule
b) Fatty acids (2 in numbers) – It is hydrophobic as it is uncharged and non polar in nature
c) Phosphate group (with alcohol) – It is hydrophilic as it is negatively charged and polar in nature.
When the phospholipids are placed in water, the molecule rearranges itself in a way that the hydrophobic head face inside and the hydrophilic head face outside thereby forming micelles.
Hence, option 1 is correct
The barnacles are only able to attach them selfs to surfaces in the water. Since the surface is limited, barnacles are attaching themselves to the other barnacles, crowding the rock. The muscles were not able to grow or attach themselves off the surface of the rock. Same thing with the mussels that are growing on the rock. So not only barnacles are crowding the rock, but Mussels as well are crowding the rock.
Answer:
Benedict's Reagent: A Test for Reducing Sugars In lab, we used Benedict's reagent to test for one particular reducing sugar: glucose.
Explanation:
Answer:
Amino acids
Explanation:
Nitrogen is a major part of amino acids. Which are the building blocks of proteins and nucleic acids.
