What forms of life were present during Earth's first age, the Hadean era?

A. Crustaceans and fish but no land animals

B. Bacteria

C. The same life that is present today

D. None

Is it possible for Michael and Danielle to have a child who has type O blood? How do you know this? Was a switch made at the hospital? Explain your reasoning. How could fraternal twins be as different in appearance as Michelle and Michael, Jr.

Gene therapy is an integral part of genome projects. It includes the correction of abnormal genes responsible for diseases. Which of these is an application of gene therapy?

Natural selection and its evolutionary consequences provide a scientific explanation for (1) the fossil record of ancient life-forms (2) predictions about the rate of global warming (3) the amount of precipitation in a rain forest (4) the amount of

The organ with the most acidic contents in the digestive system is the a. pancreas c. stomach b. mouth d. small intestine

The diagram below shows part of the process of DNA transcription. Which mRNA base will go in location 1? A. Uracil B. Cytosine C. Adenine D. Thymine

How many chromosomes do humans have?

Pairing of homologous chromosomes in prophase of meiosis I appears to be critical for proper alignment, crossing over, and subsequent separation. This pairing is facilitated by the sharing of sequence homology between homologous chromosomes.

What does "leeward" mean?

Which lipid acts as a chemical messenger? a. adipose tissue b. cholesterol c. testosterone d. beeswax

The degradation of alanine yields pyruvate and the degradation of leucine yields acetyl coa. can the degradation of each of these amino acids directly replenish the pool of tca intermediates? explain why or why not.