What is the most difficult part of a controlled experiment?

1.) testing only one variable

2.) testing two variables

3.) testing multiple variables

4.) testing zero variables

How many pairs of chromosomes exist in each of your cells?

He three d's for group-living primates are:

Often the growth cycle of one population has an effect on the cycle of another. As moose populations increase, wolf populations also increase.

Under what conditions might the morphological species concept be used instead of the biological species concept? a. It is clear that one species evolved into another, based on fossils. b.

Reasearch is done only after a hypothesis is written

What activity will decrease body temperature? Sweating Exercising Adding clothing Shivering

Organisms with true radial symmetry A. tend to be highly mobile. B. do not have a distinct head region and tend to be sedentary or passive drifters. C. can be divided into two matching halves along only one plane. D.

1. The Earth's carbon cycle consists of the flow, cycling, and recycling of all of the carbon on the Earth. Every living organism's composition includes the element carbon. How does carbon become part of living organisms?

Which of these is used to find the precise age of a rock? Index fossils Radioactive dating Relative dating Stratified rock layers

Mi ola designs swimsuits for women who are athletic in the water, and the swimsuits have design features that allow them to stay on during physical activity. this indicates that mi ola has a. check all that apply.