A balance must exist between substances entering and exiting cells. Most animals take in substances by

What would happen if human sperm and eggs were produced by mitosis?

In a study of proteins mediating cell membrane transport, microbiologists measure current versus time through the cell membranes of oocytes (nearly mature egg cells) taken from the African clawed frog, Xenopus.

Although the brain's early development is in large part genetically directed, its structure is continually modified by environmental experiences and this modifiability is called

If humans have altered that natural environment, describe the changes made by humans and their impact on the species.

What happens during primary succession?

Describe what is happening to the chromosomes during each sub-phase of Meiosis I and Meiosis II.

What accounts for genetic biodiversity existing in modern multicellular organisms?

Torri and Tamara are both performing scientific investigations on the learning capabilities of mice. In Torri's experiment, she sets up two knobs in a cage with a mouse. When the mouse touches the knob on the left, it receives a small shock.

What did Chargaff discover while studying bases in the DNA of organisms?

Russia's system of government and identify its basic structure.