Answer:
Three Domains of Life
The scheme most often used currently divides all living organisms into five kingdoms: Monera (bacteria), Protista, Fungi, Plantae, and Animalia.
Explanation:
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.
Incomplete Dominance
Explanation:
Incomplete dominance is an example of a non-mendelian trait (doesn't follow the genetic rules established by Gregor Mendel). When two parents mate and produce offspring, the offspring is a blend of the two parents. So, a red flower and a white flower would make a pink flower.
Answer:
The main difference is the presence of a nucleus.
Explanation:
One of the biggest differences is the presence of a nucleus with an envelope. This is very important because in eukaryotes it is present, but in prokaryotes, the genetic material is in the cytosol, although it's not exactly dispersed, it's slightly grouped. Also, the DNA in prokaryotes is organized in circular chromosomes while in eukaryotes it's organized in linear chromosomes arranged in an X shape. There are many more differences, but these two are the more important ones.
