The pair of characteristics that one must use to classify a fish is the presence of jaw and skeleton type. Agnatha fishes are also called jawless fishes and they lack bony skeletons. Cartilaginous fishes are composed of cartilage skeletons. Bony fishes have bony skeleton structures.
Answer:
1) B - protein channel
2) D - to assist in the movement of substances across the membrane by facilitated diffusion or active transport
Explanation:
1) B is the answer because the proteins would travel through the protein channel to enter or leave the cell.
2) D is the answer because the channel allows protein molecules to pass through a selectively permeable cell membrane through active transport and facilitated diffusion.
Hope this helps!
Answer:
The correct answer is - D. natural selection.
Explanation:
Sexual selection takes place due to competition between individuals of the intraspecies same-sex and of mate choice which driving the evolution of reproductive traits.
Sexual selection is a mode of natural selection as it leads to the evolution of specific traits. Other examples or options are not related to sexual selection directly and are not affected by sexual selection.
There are three populations
you= 1 population
dog= 1 population
Cat= 1 population
total =3 populations.
Tigers are a very important part of the food chain, but sadly they are going extinct. Their habitats are being destroyed, forcing the tigers to kill farmers livestock. In some countries tigers are still used for medicinal purposes, so they are often hunted for their teeth and pelts. Tigers may not seem important but they play a very important part on the food chain. Without these tigers the population of boars and other prey would sky-rocket and that would not be good for the environment.
