A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 25% of the animals display a recessive trait (aa), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants. What is the estimated frequency of allele A in the gene pool? A) 0.25 B) 0.50 C) 0.75

As a result of climate change earths temperature is rising and sea ice is melting what is a likely effect? answer : populations of walruses and polar bears will decline

Question 1 which of the following allows cells to take in fluids? a. phagocytosis b. pinocytosis c. exocytosis d. receptor-mediated endocytosis question 2 molecules move along their concentration gradient (from areas of high concentration to low concentration) using active transport mechanisms. a. true b. false question 3 which of the following powers active transport (ie. provides the energy for)? a. glucose b. transport proteins c. atp d. phospholipids question 4 what type of lipid is a major component of the plasma membrane? a. cholesterol b. phosopholipids c. proteins d. triglycerides

The genetic code is essentially the same for all organisms. based on this information, one can logically assume which of the following statements to be correct? a. dna was the first genetic material. b. the same codons in different organisms translate into the different amino acids. c. different organisms have different numbers of different types of amino acids. d. a gene from an organism can theoretically be expressed by any other organism. e. all organisms have experienced convergent evolution.