At the end of the pleistocene, there are a series of extinctions in which the majority of large mammals go extinct. why of these is a hypothesized cause of the extinction?
a. meteor impact
b. increased volcanism
c. glacial-interglacial cycles
d. human induced climate change
e. all of the above are hypothesized causes

The correct option is: c. glacial-interglacial cycles

Explanation:

Pleistocene, also known as the Ice Age, is a geological epoch that is dated about 2.588 million to 11,700 years before present.

At the end of Pleistocene, the last glacial period ended and it also corresponds to the extinction of large mammals.

The cause of the extinction during Pleistocene is considered to be a combination of many factors such as human predation, climate change, interspecific competition, and unstable population dynamics.

answer; ///(b) it is composed of four protein chains and four heme groups;

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!