A, b, and c are all correct.
take for example finches off of the galapagos islands. they vary from island to island, yet are still the same bird. on one island they have bigger, more durable and stronger beaks, because that island has many nuts to crack open and eat. on another island, they have thin ling beaks, ideal for pecking at insects in the grass on tree bark. evolution is literally survival of the ifttest, where those equipped best will live and those without means to fight for life will die off, leaving those most capable of reproduction and passing down genes.
Communication refers to a state when one animal conducts information to another animal making a certain type of modification in the animal, which acquires the information. Animals generally communicate using signals that may involve visual, auditory or sound based; chemicals involving pheromones, and others.
A pheromone refers to a discharged chemical signal used to stimulate a reaction in another individual of the similar species. Pheromones are generally common among social insects, like bees and ants. It is used to fascinate the opposite sex, mark a food trail, raise an alarm, or to stimulate other composite behaviors.
This kind of communication plays an essential role in natural selection. It helps in obtaining mates, establishing defending or dominance territory.
Answer:
Total 40 sister chromatids
Explanation:
A cell cycle comprises of various phases that includes G1 phase, S phase, G2 phase, Mitosis and cytokinesis.
- During G1 phase the cell grow in size and almost all of the content of cell is duplicated except the DNA. The cell contains chromosome with a single copy of DNA.
- During S phase the the the DNA is duplicated and each cell have chromosome with two sister chromatids.
- G2 phase came after the DNA duplication and recheck the DNA duplication for errors.
As G2 phase occur after DNA duplication so each chromosome in this phase contains two sister chromatids that's why the corn plant with 20 chromosomes would contain 40 sister chromatids in G2 phase.
