Why must organisms of the estuary be adapted to varying levels of salinity? A. Fresh river water flows into the estuary

B. Saline ocean water flows into the estuary

C. Ocean tides increase and decrease the amount of ocean water

D. All of the above

How is information for a specific protein carried on the dna molecule

Cells can increase the number or size of some organelles in response to new demands. the amount of one organelle often is increased dramatically in the livers of alcoholics. based on what you know of organelle function, this organelle is the.

You are given a sample of unknown cells to examine. Analysis of their nuclei reveals that each cell contains 23 chromosomes. What types of cells might these be? a. Ova b. skin cells c. liver cells d. white blood cells

The uncontrolled division of cells may result in a malignant growth is known as

True or false. during sperm maturation, secondary spermatocytes are the products of meiosis ii that go on to form spermatids, which undergo restructuring to form spermatozoa.

One of the main differences between natural selection and genetic drift is that A) genetic drift happens by chance B) genetic drift populations introduce new species C) genetic drift populations are selected by nature D) genetic drift populations

Hatchetfish live in very deep parts of the ocean. What challenges must they overcome to survive in this environment?

The movement of air particles around a vibrating object is a

About how much of the United States is covered by forests? A 90% B 10% C 50% D 30%

What is the layer underground where all empty spacess are filled with water