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.

A student reads the article "Autoimmune Diseases Stopped in Mice" and claims that this research will revolutionize treatment for autoimmune disorders in just a few years.

A photon of ultraviolet light hits double-stranded dna and creates a covalent cross-link between adjacent thymines in the same strand (a thymine dimer). what is likely to happen?

When trees transpire releasing gaseous water into the atmosphere make another key from the environment include what property of water is responsible for this activity

All BUT one is a function of the cell wall. That is

Horizontal tectonic movements usually produce which type of metamorphism? heated intrusive regional contact

Which route represents the path taken by the European explorer Christopher Columbus? A) 1 B) 2 C) 3 D) 4

Which gas is the most abundant of the trace gases? A. nitrogen B. oxygen C. argon D. carbon dioxide

Describe the central dogma of molecular biology, briefly describe the processes of transcription and translation.

magine that the animal body produced sperm and eggs with mitosis instead of meiosis. What chromosome number would the autosomes of the third generation have if the first generation had four chromosomes

A well supported testable explanation of phenomena that have occurred in the natural world is called