Lyme disease is spread by ticks that attach to an animal to feed. Which describes the role of the tick?

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.

Red blood cells are responsible for transporting oxygen in the blood. people with sickle cell anemia were born with a defective gene that results in sickle-shaped red blood cells. individuals with the disease often suffer pain in their extremities due to the build-up of these cells causing blockages in the blood vessels. the shape of the blood cells also reduces the amount of oxygen transported in the blood.

Imagine that you are a doctor in a maternity ward. during your last shift, 20 babies were born. 10 had blue eyes, and 10 had brown eyes. 15 had round heads, and 5 had pointed heads. what are the parents phenotypes/traits?