Suppose a population of crabs in a certain tidal ecosystem thrives. These male crabs have one large claw and one small claw, but variation exists in the size of the large claw. They wave the large claw to attract females to their burrow. Females are attracted to males with larger claws. Which crabs will be more likely to have more offspring in this environment?

The population having one large claw will have more offspring as compared to the ones having smaller claw.

Explanation:

A population of crabs has two types of crabs in it, one with larger claw and other with smaller claw. They will try to attract the female crab in order to mate.

The males having larger claw are more attractive to the females. Females choose to prefer larger claw over smaller claw because they will have a big burrow which will help her incubate her eggs and they are older (survivor)because the crustaceans grow majority of their life.

So, the crab with large claw is likely to have more offspring than other one.

1. Action potential reaches the axon terminal and depolarizes it.

2. Depolarization opens voltage-gated calcium channels, enabling influx of Ca into the neuron.

3. Calcium binds to specialized proteins on vesicles (containing pre-made acetylcholine) and triggers them to fuse with the neuron membrane at the synapse.

4. Exocytosis of acetylcholine into the synaptic cleft occurs.

5. Acetylcholine diffuses across the synapse and binds to nicotinic receptors on the end plate of the myocyte.

6. Activated nicotinic receptors, themselves ion channels, cause cation influx into the myocyte and generate an end plate potential. This eventually gives rise to the full depolarization within the myocyte that enables contraction.