CHAPTER 1

Question 1

is the process by which sperm and ovum (sex cells) combine to create a single cell called zygote, which then duplicates itself again and again by cell division.

Answer 1

Fertilization

Question 2

rupture of mature follicle in either ovary and expulsion of its ovum which occurs every month until menopause

Answer 2

Ovulation

Question 3

Two separate eggs being fertilized by two different sperms; also known as fraternal twins

Answer 3

Dizygotic Twins

Question 4

resulted from the cleaving of one fertilized egg and are generally genetically identical

Answer 4

Monozygotic Twins

Question 5

genetic transmission of heritable characteristics from parents to offspring

Answer 5

Hereditary

Question 6

long, spiraling ladder whose steps are made of pairs of chemical units called bases

Answer 6

Deoxyribonucleic Acid

Question 7

coils of DNA of smaller segments called genes

Answer 7

Chromosomes

Question 8

mistake in copying genetic code which creates permanent alteration in genetic material

Answer 8

Mutation

Question 9

produce alternative expressions of characteristics

Answer 9

Alleles

Question 10

observable characteristics

Answer 10

Phenotype

Question 11

underlying genetic makeup

Answer 11

Genotype

Question 12

environment can influence when and which genes turn on and off

Answer 12

Epigenesis

Question 13

extra copy of chromosome 21

Answer 13

Down Syndrome

Question 14

extra x chromosome (xxy)

Answer 14

Klinefelter Syndrome

Question 15

abnormality in X chromosome causes ID

Answer 15

Fragile x syndrome

Question 16

missing x chromosomes for females

Answer 16

Turner Syndrome

Question 16

extra y chromosome

Answer 16

XXY Syndrome

Question 17

overproduction of mucus in the lungs and digestive tract

Answer 17

cystic fibrosis

Question 18

does not produce enough insulin

Answer 18

diabetes

Question 19

delayed blood clotting

Answer 19

Hemophilia

Question 20

CNS deteriorates producing problem in muscles and mental decline

Answer 20

Huntington’s

Question 21

build up of Phenylalanine in the body

Answer 21

Phenylketonuri

Question 22

limits body oxygen supply

Answer 22

Sickle-cell anemia

Question 23

incompletely closed spinal canal

Answer 23

spina bifida

Question 24

accumulation of lipids in the ns

Answer 24

tay-sachs disease

Question 25

absence of brain tissue

Answer 25

anencephaly

Question 26

enlarged kidneys

Answer 26

polycystic kidney disease

Question 27

cirrhosis of the liver in early infancy

Answer 27

alpha antitrypsin deficiency

Question 28

severe anemia; nearly all die soon after birth

Answer 28

alpha thalassemia

Question 29

severe anemia; fatal in adolescence or young adulthood

Answer 29

beta thalassemia (cooley's anemia)

Question 30

males with muscle weakness, minor mental retardation

Answer 30

duchenne muscular dystrophy

Question 31

high frequency sound waves are directed into the women's abdomen

Answer 31

ultrasound sonography

Question 32

uses powerful magnet and radio images to generate detailed images of the body's organs and structures

Answer 32

Fetal MRI

Question 33

small sample of placenta is removed

Answer 33

Chorionic Villus Sampling

Question 34

sample of amniotic fluid is withdrawn and tested for chromosomal and metabolic disorders

Answer 34

amniocentesis

Question 35

identifies pregnancies that have an elevated risk for birth defects

Answer 35

maternal blood screening

Question 36

period between conception and birth

Answer 36

Gestation

Question 37

dated from the first day of an expectant mother's last menstrual cycle

Answer 37

gestational age

Question 38

development proceeds from head to the lower extremities

Answer 38

cephalocaudal principle

Question 39

development proceeds from the center to outer parts of the body

Answer 39

proximodistal principle

Question 40

specialization of the cells to perform various tasks

Answer 40

differentiation

Question 41

fluid-filled sphere which floats freely in the uterus until 6th day after fertilization then it implants itself in the uterine wall

Answer 41

blastocyst

Question 42

outer layer of cells that later provides nutrition and support for the embryo

Answer 42

trophoblast

Question 43

outer layer (becomes outer layers of skin, nails, hair, teeth, sensory organs, and the nervous system)

Answer 43

ectoderm

Question 44

inner layer (becomes digestive system)

Answer 44

endoderm