Down syndrome is a condition in which the individual

a. has three copies of chromosome 21.

b. has three copies of chromosome 23.

c. lacks chromosome 46.

d. has only one chromosome 21.

Which of these cells of the dermal tissue of plants prevent water loss in control gas exchange

For ease of swallowing oral solid medications, place the drug on the back of the tongue. a. True b. False

The process of natural selection is based on the assumption that: (1) environmental changes will cause changes in body structure in individuals (2) most changes from generation to generation are the result of mutations (3) part of the population of

Sperm whales, a (n) species, maintain their populations close to carrying capacity.

If genes come in pairs, each parent will have two for each protein. Why don't the offspring have four genes for each protein?

What two things get thrown out of a cinder cone volcano

Choose the FALSE statement about rocks. A. They are natural substances. B. They must form from solid materials. C. They can form above or below ground. D. They are made of one or more minerals.

Description and function of a phospholipid

English maths biology physics account

Hallie and Jamar built a prototype bridge for a science competition. According to competition guidelines, their final design must hold at least 2 kilograms and span a gap of 0.5 meters. They built a bridge that is 0.75 meters long.