Elk are members of the deer family. These herbivores move in herds from the high mountain pastures to the lower valleys and wooded areas throughout the seasons. Their fur color ranges from gray to dark brown which allows them to blend into the dense wooded areas. Natural enemies of the elk include bears, cougars, wolves, and coyotes. The graph below shows how the number of elk in an area has changed over time. Based on the data, one student concludes that an elk predator was introduced into the area during this time period. Which of the following is a likely alternate explanation for the change in the elk population? A. Elk prey increased in the area.

B. The temperature of the area remained constant

C. Elk parasites decreased in the area.

D. The amount of plants in the area decreased.

answer: wheres the options

explanation:

endo:

regulates body hormones, aldosterone, vasopressin

neural:

signal, regulates body using electric signals, reflex

endo has to do with hormones; aldosterone and vasopressin are both hormones. i also had this question and got it right : d

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!