Reproduction & Development
Once an egg cell is fertilized by sperm, the cell _______. Then, as the embryo develops, it receives nourishment and eliminates wastes by transferring substances from its blood to its mother's blood.
begins to divide and implants itself in the wall of the uterus
The embryo develops its essential organs in the early stages of pregnancy. During this time, many things can harm the embryo if the mother is exposed to them. Which of the following of the mother's behaviors will likely result in harm to the embryo?
drinking alcohol several times a day
Immediately after the cells differentiate—become particular kinds of cells—they begin to form tissues. When does heart tissue first form in a human?
during the first trimester of pregnancy
Most mammals have diploid body cells and haploid gametes. During __________, chromosomes from haploid gametes combine, and a __________ zygote is formed.
fertilization, diploid
What is the name of the organism growing in a woman's uterus during pregnancy?
fetus
The female reproductive system in humans differs from the human male reproductive system in that it is solely responsible for
nourishing a developing zygote.
Which of the following is considered the primary sex organ in a human female and is responsible for the production of gametes?
ovary
Almost all living things are able to produce offspring during their life cycles. In mammals, the organ system responsible for the production of offspring does not mature until the mammal reaches puberty. Which of the following organ system is involved in the production of offspring?
reproductive system
What is the main function of the human reproductive system?
the production of gametes
During fertilization, a sperm cell unites with an egg cell to form a(n) _______.
zygote