In order for cells in multicellular organisms to exchange gases, a circulatory system must be present.

a. true

b. false

Amino acids, sugars, and ions move across the cell membrane. Their movement from a region of high concentration to a region of low concentration is accomplished by special proteins in the membrane.

What is the uppercase letter represents in a punnett square

Aquatic biomes can be distinguished by chemical characteristics such as dissolved oxygen content and salinity and by physical characteristics such as water flow. Which five of the following statements about aquatic biomes are true?

What are renewable sources of energy better than nonrenewable sources? A. because we will not run out of them B. Because they are fossil fuels C. Because they are more expensive D. Because they release greenhouse gas

What are the 26 bones of the spine called?

If a small founder population of 12 people ends up on a small island, and one member of the population had a mutation that creates a new allele, what is the likelihood that the allele will be eliminated from the population?

Homologous structures (Group of answer choices): A. are also called analogous structures. B. have identical functions. C. are shared by organisms of the same genus. D. have fully divergent functions. E.

Which of the following is true of an enzyme? (mark all that apply) a. it is a protein b. it is a catalyst c. it binds to many different substances d. it is small compered to its substrates

Which term would be applied to a regulatory condition that occurs when protein is associated with a particular section of DNA and greatly reduces transcription? A) induction B) negative control C) stimulation D) positive control E) activation

1. The reproductive parts of angiosperms are located within the called the and the female part is called the The male part is 2. In angiosperms, pollen produces cells. Pollen sticks to the female and travels down the style to the ovary.