chapter two Flashcards
evolutionary psychology
emphasizes the importance of adaptation, reproduction, and “survival of the fittest” in shaping behavior.
chromosomes
threadlike structures made up of deoxyribonucleic acid, or DNA.
DNA
complex molecule
with a double helix shape, like a spiral staircase
Genes
the units of hereditary information, are short segments
of DNA.
mitosis
Cellular reproduction in which the cell’s nucleus duplicates itself with two new cells being formed, each containing the same DNA as the parent cell, arranged in the same 23 pairs of chromosomes.
meiosis
A specialized form of cell division that occurs to form eggs and sperm (or gametes).
fertilization
stage in reproduction whereby an egg and a sperm fuse to create a single cell, called a zygote.
zygote
A single cell formed through fertilization.
Down syndrome
A chromosomally transmitted
form of mental retardation, caused by the presence of an extra copy of chromosome 21.
Klinefelter syndrome
A chromosomal disorder in which males have an extra X chromosome, making them XXY instead of XY.
fragile X syndrome
A genetic disorder involving an abnormality in the X chromosome, which becomes constricted and often breaks.
Turner syndrome
A chromosome disorder in females in which either an X chromosome is missing, making the person XO instead of XX, or the second X chromosome is partially deleted.
XYY syndrome
A chromosomal disorder in which males have an extra Y chromosome.
phenylketonuria (PKU)
A genetic disorder in which an individual cannot properly metabolize an amino
sickle-cell anemia
A genetic disorder that affects the red blood cells and occurs most often in people of African descent.
