Answer:
2.Bees and the butterflies take nutrients away from the flowering plants.
4.Bees and butterflies pollinate the flowers by flying from one to another without any harm to themselves.
Explanation:
Answer:
Yes, the answer is wood.
Explanation:
Wood is a natural material and is subject to variations in composition and moisture content. Therefore the energy from burning it or gasifying it would likewise be variable.
not sure what the purpose of this question was, but here's the explanation anyway! have a nice day.
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:
1. Leads to mixing of genetic materials hence variation within species
2. Leads to offspring with hybrid viguor that tend to show high and adaptability to environmental conditions.
3. Variations due to sexual reproduction leads to improvement of species hence evolutionary changes that may bring about specialisation
