Ch. 2 Vocab

Question 1

23 matching pairs of rod-shaped structures located in the nucleus

Answer 1

chromosomes

Question 2

a complex molecule shaped like a twisted ladder or staircase

Answer 2

deoxyribonucleic acid (DNA)

Question 3

the blueprint for creating all of the traits that organisms carry

Answer 3

genes

Question 4

the process which DNA replicates itself, permitting the duplication of chromosomes and ultimately the formation of new cells with identical genetic material

Answer 4

mitosis

Question 5

how sex cells reproduce; like mitosis but chromosomes complete “crossing over”

Answer 5

meiosis

Question 6

the cells of sexual reproduction; sperm (in males) and ova (in females)

Answer 6

gametes

Question 7

fertilized egg

Answer 7

zygote

Question 8

ovary

Answer 8

ovum

Question 9

when more than one ovum is released and each is fertilized by two different sperm; fraternal twins

Answer 9

dizygotic (DZ) twins

Question 10

occurs when zygote splits into two distinct separate but identical zygotes; shares same genotype with identical instructions for all physical and psychological characteristics; identical twins

Answer 10

monozygotic (MZ) twins

Question 11

chromosomes expressed in different forms that influence a variety of physical characteristics

Answer 11

alleles

Question 12

when alleles of the pair of chromosomes are alike with regard to a specific characteristic

Answer 12

homozygous

Question 13

when alleles of the pair of chromosomes are different with regard to a specific characteristic

Answer 13

heterozygous

Question 14

when some genes that are passed through are always expressed regardless of the gene they are paired with while other genes will be expressed only if paired with another recessive gene

Answer 14

dominant-recessive inheritance

Question 15

when an individual is heterozygous for a particular trait and the dominant trait is expressed, this individual becomes a

Answer 15

carrier

Question 16

genetic inheritance pattern in which both genes influence the characteristic

Answer 16

incomplete dominance

Question 17

causes red blood cells to become crescent, or sickle, shaped; about 5% of African Americans newborns carry this recessive trait

Answer 17

sickle cell trait

Question 18

most traits are a function of the interaction of many genes

Answer 18

polygenic inheritance

Question 19

refers to the instance in which the expression of a gene is determined by whether it is inherited from the mother or the father

Answer 19

genomic imprinting

Question 20

a common recessive disorder that prevents the body from producing an enzyme that breaks down phenylalanine (an amino acid) from proteins

Answer 20

phenylketonuria (PKU)

Question 21

a dominant-recessive disorder carried on the X chromosome; an intellectual disability

Answer 21

Fragile X syndrome

Question 22

a condition in which the blood does not clot normally; a recessive disease inherited through genes on the X chromosomes

Answer 22

hemophilia

Question 23

most widely known chromosome disorder; trisomy 21; an extra chromosome; occurs in about 1/1500 births

Answer 23

down syndrom

Question 24

males are born with an extra X chromosome

Answer 24

Klinefelter syndrome

Question 25

a condition that causes men to produce high levels of testosterone

Answer 25

Jacob's syndrome

Question 26

occurs when a female is born with only one X chromosome; shows abnormal growth patterns

Answer 26

Turner syndrome

Question 27

sudden changes and abnormalities in the structure of genes that occur spontaneously or may be induced by exposure to environmental toxins such as radiation and agricultural chemicals in food

Answer 27

mutations

Question 28

helps to determine the risk that a couple's future children will inherit genetic defects and chromosomal abnormalities

Answer 28

genetic counseling

Question 29

the injection of sperm into a women

Answer 29

artificial insemination

Question 30

conception occurring outside of the womb

Answer 30

in vitro fertilization

Question 31

alternative form of reproduction in which a women is impregnated and carries a fetus to term and agrees to turn the baby over to a couple who will raise the it

Answer 31

surrogacy

Question 32

high-frequency sound waves directed at the mother's abdomen provide clear images of the womb represented on a video monitor

Answer 32

ultrasound

Question 33

applies MRI technology to image the fetus's body and diagnose malformations

Answer 33

fetal MRI

Question 34

a prenatal diagnostic procedure in which a small sample of the amniotic fluid that surrounds the fetus is extracted from the mother's uterus through a long, hollow needle that is guided by ultrasound as it is inserted into the mother's abdomen

Answer 34

amniocentesis

Question 35

samples genetic material and can be conducted earlier than amniocentesis, between 9 and 12 weeks of pregnancy

Answer 35

chorionic villus sampling (CVS)

Question 36

a technique that uses a small camera to examine and perform procedures on the fetus during pregnancy

Answer 36

fetoscopy

Question 37

genetic makeup

Answer 37

genotype

Question 38

the traits we ultimately show

Answer 38

phenotype

Question 39

the field of study that examines how genes and experiences combine to influence the diversity of human traits, abilities, and behaviors

Answer 39

behavioral genetics

Question 40

the extent to which variation among people on a given characteristic is due to genetic differences

Answer 40

heritability

Question 41

the dynamic interplay between our genes and our environment

Answer 41

gene-environment interactions

Question 42

a wide range of potential expressions of a genetic trait, depending on environmental opportunities and constraints

Answer 42

range of reaction

Question 43

heredity narrows the range of development to only one or a few outcomes

Answer 43

canalization

Question 44

the idea that many of our traits are supported by both out genes and environment

Answer 44

gene-environment correlation

Question 45

the tendency to actively seek out experiences and environments compatible and supportive of our genetic tendencies

Answer 45

niche-picking

Question 46

our genes expressed as different phenotypes in different contexts or situations

Answer 46

epigenetics