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.
A. Twelve cells with 16 chromosomes each
Answer:
The plateau region has endemic population of species and the change in the ecology impacts the climate and wildlife of the area.
Explanation:
- The Edwards plateau is located in the south, central and western taxes. It bounded by faults and uplands. It has a base made of limestone.
- The plateau is home to various diverse species of plants and animals. The plateau region consists of 41 counties in geographic regions. Currently, about 2.26% of the land area is under protection as this region has experienced habitat loss of 5.3%.
A phobia is an intense fear of something that, in reality, poses little or no actual danger. Common phobias and fears include closed-in places, heights, highway driving, flying insects, snakes, and needles. However, you can develop phobias of virtually anything.
OR
A Phobia is an irrational fear of something that's unlikely to cause harm. The word itself comes from the Greek word“phobos,” which means “fear” or “horror.” Hydrophobia, for example, literally translates to fear of water. When someone has a phobia, they experience intense fear of a certain object or situation.
