Answer:
Biology is a branch of science that deals with living organisms and their vital processes. Biology encompasses diverse fields, including botany, conservation, ecology, evolution, genetics, marine biology, medicine, microbiology, molecular biology, physiology, and zoology.
I believe it is nervous tissue
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.
Ok so I would start by saying that light has a maximum speed, then explain that because space is so big we measure it's distance in light years and which means how light travels in a year at 186,282 miles per second Put that in perspective my saying If you could travel at the speed of light, you could go around the Earth 7.5 times in one second. Tell them Sunlight takes about 8 minutes 19 seconds to reach the Earth and that it can take millions or more light years for more distance stars light to reach our telescopes .
Answer:
They are semi-permeable, which means that some molecules can diffuse across the lipid bilayer but others cannot. Small hydrophobic molecules and gases like oxygen and carbon dioxide cross membranes rapidly.
Explanation:
