It is useful for an ecologist to identify the keystone species in an ecosystem because the keystone species is important to maintaining the stability of an ecosystem, and any changes in the keystone species population shows that there is changes in ecosystem health.
Answer:
In all different levels of the food webs and food chains, it is seen that damaged members of the prey have become easy food for the predators.
Explanation:
Preys can identify the other members of their species are injured or wounded or fed by the predators by their body fluid in as if a predator eats the prey the blood or other body fluid releases. These fluids or blood help individual prey species to be aware of the predator as they recognize that their species member is wounded or consumed by there olfactory receptors.
There are several other chemicals cue that is species specif that are released by the prey to alarm the other species member by injured or dead members.
Thus, the correct answer is - In all different levels of the food webs and food chains it is seen that damaged members of the prey have become easy food for the predators.
Answer;
-Large polar molecule are list likely to cross the phospholipid bilayer.
Explanation;
-A large polar molecule would be the least likely to passively diffuse through a plasma membrane without the help of a transport protein. Both its size and the hydrophobic interior of the membrane would restrict it.
-Only small uncharged molecules can diffuse freely through phospholipid bilayers. Small nonpolar molecules, such as O2 and CO2, are soluble in the lipid bilayer and therefore can readily cross cell membranes.
-Ions and large polar molecules cannot pass through the lipid bilayer. But more specifically, whether a molecule can pass through the membrane depends on its size and its electrical nature.
Answer: B - People with two copies of the mutated gene have sickle-cell anemia. People with one copy of the mutated gene have both healthy and misshapen red blood cells and are carriers of the disease.
Explanation:
Co-dominance is when both the alleles of a gene in a heterozygote show. In the case of sickle cell anemia (since it is a co-dominant trait) even if the person only has one sickle cell allele, symptoms of sickle cell will still show up in that person. That's why the person in this example has both misshapen and healthy red blood cells.
