Biology

How are sexual reproduction and asexual reproduction different from each other? A. sexual reproduction requires two parents and asexual reproduction requires only one parent B. asexual reproduction requires two parents and sexual reproduction requires only one parent C. mutation rates are lower in sexual reproduction than in asexual reproduction D. asexual reproduction occurs only in multicellular organisms

A. sexual reproduction requires two parents and asexual reproduction requires only one parent During sexual reproduction, genetic information from two organisms is combined. This results in genetic variation in the population.

A scientist wants to change the DNA of a sexually reproducing organism and have the new DNA present in every cell of the organism. In order to do this after fertilization, she would change the DNA in which of the following? A. zygote B. placenta C. testes of the father D. ovaries of the mother

A. zygote The zygote is the first single cell of an organism. The DNA that is present in the zygote will be replicated each time the cell goes through mitosis.

Which of the following best describes meiosis? A. It is carried out in all tissues that require cell replacement. B. It occurs only in cells in the reproductive structures of organisms. C. It happens in all tissues except the brain and spinal cord. D. It is the first stage of mitosis.

B. It occurs only in cells in the reproductive structures of organisms. Meiosis only occurs in the reproductive cells, producing gametes with half of the genetic information as the parent cell.

Which type of reproduction leads to increased genetic variation on a population? A. Parthenogenesis B. asexual reproduction C. Sexual reproduction D. Vegetative reproduction

C. Sexual reproduction During sexual reproduction, the genetic information from each parent is combined and reorganized to provide a unique new individual. This process introduces genetic variation into a population.

Mitosis and meiosis are processes involved in cellular reproduction. Which of the following describes and event that results from mitosis but NOT meiosis? A. two stages of cell division B. replication of cellular genetic material C. daughter cells that are identical to the parent cell D. four daughter cells that are produced from each parent cell

C. daughter cells that are identical to the parent cell Mitosis is the process of cell division for all cells in the body except reproductive cells. Mitosis results in daughter cells that are identical to the parent cell in every way including number of chromosomes.

Which of the following phrases best describes cancer? A. absence of cyclins in the DNA B. miltiple gene mutations on a chromosome of DNA C. uncontrolled cell growth caused by mutations in genes that control the cell cycle D. presence of genetic defects caused by hereditary disorders

C. uncontrolled cell growth caused by mutations in genes that control the cell cycle Cancer cells lack the ability to recognize and control cell growth and reproduction. As a result, they replicate again and again.