What are chromosomes?
a. the alleles that cause certain traits
b. any organism that contains dna
c. strands of dna wrapped around proteins
d. a form of virus that infects cells

Identify the various levels of atmosphere. troposphere mesosphere exosphere stratosphere thermosphere

Grasses--> mice--> cats--> coyotes suppose 10,000 units of energy are available at the level of the grasses. what is the total number of energy units lost by the time energy reaches the coyote?

Substances that can pass through cell membranes by diffusion include a. na ions. b. proteins c. glucose. d. oxygen.