Which blood vessels have thin walls and contain valves?

A. Veins

B. Capillaries

C. Arteries

D. Platelets

The human traits for red hair and freckles are closely linked on chromosome 16. Red hair is a recessive trait while having freckles is a dominant trait.

Which new phenomenon did Griffith focus on during his work with pneumonia-causing bacteria and mice?

What is the attraction between molecules of the same substance

What is a hypersaline bay?

Pangaea means "all lands" in Greek. Why is this a suitable name for a supercontinent?

Norway rats have 42 chromosomes in their diploid cells. If a diploid rat cell enters meiosis, how many chromosomes and double-helical molecules of DNA will be present in each daughter cell at the end of meiosis II?

Which discovery is attributed to Phoebus Levene? A. extraction and observation of DNA B. identification of ribose and deoxyribose C. recognition of RNA as DNA's messenger D. construction of an accurate DNA model

A small population of chimpanzees lives in a habitat that undergoes no changes for a long period. how will genetic drift probably affect this population?

Which type of cells can differentiate into many different types of cells? select all that apply

A person has such severe epilepsy that his limbs are paralyzed, and doctors recommend a radical hemispherectomy. what results can he expect?