If a male horse has 64 chromosomes in his body cells, how many chromosomes are in each of his sex cells?

What is the purpose of ATP in both cellular respiration and photosynthesis?

Cellular respiration can be expressed as the following equation:

Which of the following are cells formed by meiosis?

In sexual reproduction, gametes are —

Meiosis is an essential part of sexual reproduction. This is because meiosis creates sex cells that have —

In cattle, the allele for short horns (S) is dominant over the allele for long horns (s). Two short-horn cows are bred and produce four offspring. Three have short horns and one has long horns. What are the most likely genotypes of the parents?

Blood type is controlled by inheriting any two of the following alleles: |^A, |^B, or II.

|^A codes for type A blood. |^B Codes for Type B blood. Both |^A and |^B are codominant. The I allele is recessive and will cause Type O blood whenever two copies of the allele are present.

If a mother has Type AB blood (|^A|^B) and a father has Type O blood (II), what percentage of their children are likely to have Type A blood?

A variety of corn can produce yellow or white seeds. Yellow is dominant. White is recessive. If an ear of corn contains only white corn, it must be —

In guinea pigs, the allele for rough coat (R) is dominant over the allele for smooth coat (r). A heterozygous guinea pig and a homozygous recessive guinea pig are mated. Which of the following would be the percentages of possible offspring phenotypes?

If a defective gene occurs on the X-chromosome, it will normally be transmitted to male offspring only by —

During prophase, chromosomes become visible, the spindle forms, and the nucleolus and nuclear envelope disappear. In which cellular process does prophase occur?

In certain rats, the allele for black fur is dominant over the allele for white fur. If two rats that are both heterozygous for fur color are mated several times, their offspring would be expected to have —

Delray has dimples and his wife does not. Delray has a homozygous dominant genotype for dimples, and his wife has a homozygous recessive genotype for no dimples. If Delray and his wife decide to have children, then which Punnett square correctly shows the probability of them having a child with dimples?

If single-celled organisms did not undergo the cell cycle, they could not —

A student is investigating mitosis by examining detailed pictures of the process. The student wants to observe the formation of the nuclear envelope around the chromosomes. The student should focus on pictures of which phase of mitosis?

Which of the following will increase the rate at which carbon dioxide is being added to the Earth’s atmosphere?

A food chain contains oak trees (producer), mice (herbivore), black rat snakes (carnivore), and bald eagles (carnivore). If these organisms were placed in an energy pyramid, which organism would be in the energy level with the second-most amount of energy available?

Bacteria in soil converts nitrogen from the air and decaying biotic material into nitrates that are used by plants to produce protein. How does this process benefit the ecosystem?

Which diagram best represents mitotic cell division?

Oxpeckers are birds that sit on zebras and rhinos and eat ticks and other parasites that live on their skin. The oxpeckers get food and, in return, the zebras and rhinos get pest control. When there is danger, the oxpeckers fly upward and scream a warning to help the zebras and rhinos.

Which of the following correctly identifies the symbiotic relationship between the oxpeckers and the zebras?

Enzymes are proteins that help increase the rate of chemical reactions inside cells. These proteins are composed of many simpler molecules called amino acids. Which of the following suggests that the shape of an enzyme determines the enzyme’s function?

How does the cell membrane help maintain homeostasis for the cell?

In 1960, scientists discovered a molecule that was used to carry genetic information in the nucleus to ribosomes. This information is used to make proteins that are used to perform various functions for an organism. Which biomolecule is used to transmit genetic information?

Diffusion and osmosis are both vital to cell function. Diffusion and osmosis are similar in that they are both types of –

Carbohydrates and lipids both serve as a source of energy for organisms. What kind(s) of energy are provided by carbohydrates and lipids?

One of the main functions of the semi-permeable cell membrane is to maintain homeostasis for the cell. Semi-permeable means that only some molecules are allowed to cross the membrane and others are not. What molecule enables large molecules to cross the membrane?

Which group of organelles is directly responsible for the production of new molecules within a cell?

Which of the following describes osmosis?

A scientist observes two cells. Cell 1 and Cell 2 both contain DNA (genetic material) and ribosomes. However, Cell 1 contains a nucleus and other membrane-bound organelles, which Cell 2 does not.

What is the correct classification for each of the cells?