Chapter 3

Question 1

Fertilization

Answer 1

Union of sperm an ovum to produce a single-celled zygote

Question 2

Zygote

Answer 2

One-celled organism resulting from fertilization

Question 3

Dizygotic twins

Answer 3

Conceived by the union of two different ova with 2 different sperm cells (fraternal twins) - share 50% of genes

Question 4

Monozygotic

Answer 4

Twins resulting from the division of a single zygote after fertilization (identical twins) - sharing 100% of genes

Question 5

What are factors resulting in multiple birth rates?

Answer 5

Delaying childbirth until an older age

Increasing use of fertility drugs

Question 6

Related risks to multiple births

Answer 6

Pregnancy complications
Premature delivery and lower birth weight
Infant disability or death

Question 7

True or False

Age at first birth is increasing, birth at an age > 35 increases risks

Answer 7

True

Question 8

Multiple births have gone up ___% since year _____

Answer 8

78%

1980

Question 9

Chromosomes

Answer 9

Coils of DNA that consist of genes

Question 10

Human genome

Answer 10

Complete sequence of genes in the human body

Question 11

Genes

Answer 11

Functional units of heredity

Question 12

Meiosis

Answer 12

Sex-cell division

Question 13

Mitosis

Answer 13

Cell division

Question 14

Mutation

Answer 14

Permanent alterations in genes or chromosomes that may produce harmful characteristics

Question 15

Heredity

Answer 15

Genetic transmission of heritable characteristics from parents to offspring

Question 16

DNA

Answer 16

Chemical that carries inherited instructions for the development of cellular life

Question 17

________(mother/father) determines the sex of the baby

Answer 17

Father

Question 18

Autosomes

Answer 18

Chromosomes not related to sexual expression

Question 19

Dominant

Answer 19

Pattern of inheritance in which, when a child receives different alleles, only the dominant one is expressed

Question 20

Recessive

Answer 20

Pattern of inheritance in which, when a child receives identical recessive alleles, results in expression of a non dominant trait

Question 21

Alleles

Answer 21

Genes that can produce an alternative expression of a characteristic

Question 22

Polygenic inheritance

Answer 22

Interaction of several genes for a trait (ex: no gene for intelligence, large number of genes working together)

Question 23

Homozygous

Answer 23

Identical copies of a gene

Question 24

Heterozygous

Answer 24

Different copies of a gene

Question 25

Phenotype

Answer 25

Observable expression of genetic makeup - product of the genotype

Question 26

Genotype

Answer 26

Actual genetic makeup or allele combinations

Question 27

Multifactorial transmission

Answer 27

Experience modifies the expression of a genotype - nature vs nurture

Question 28

True or False Most birth disorders are rare, only 3% occur in live births

Answer 28

True

Question 29

Birth disorders account for _____% of all deaths in the 1st year

Answer 29

19.5%

Question 30

Chromosomal abnormalities include:

Answer 30

Errors in cell division Result in mission or extra chromosomes Can occur in sex chromosomes or autosomes

Question 31

What is the #1 and #2 genetic abnormalities?

Answer 31

1. Cleft palate | 2. Down syndrome

Question 32

Down syndrome

Answer 32

aka Trisomy 21 - extra 21st chromosome

Question 33

What is the most common autosomal disorder?

Answer 33

Down syndrome

Question 34

___% of all cases of down syndrome have moderate to severe mental retardation

Answer 34

40%

Question 35

Where are the areas of the brain that shrink in volume by adulthood in people with down syndrome?

Answer 35

Hippocampal area/prefrontal cortex - cognitive dysfunction | Cerebellum - motor coordination

Question 36

There is an increased risk for early death in people with down syndrome because of what factors?

Answer 36

Increased chance of leukemia Cancer Alzheimer's CVD

Question 37

Concordant

Answer 37

Term describing tendency of twins to share same disorder

Question 38

Heritability

Answer 38

Statistical estimate of heritable influence on trait variance in a population (how much of a trait is due to genetics and how much is it as a result of environment?)

Question 39

Reaction rage

Answer 39

Potential variability, depending on environmental conditions, in the expression of a hereditary trait ex: child born w/ mild cognitive delay can respond to environment more than child born w/ severe limitations

Question 40

Intelligence

Answer 40

Heredity exerts a strong influence Polygenic trait; influence by the additive effects of large numbers of genes working together Brain size and structure Genetic influence - responsible for stability in cognitive performance increases with age