Chapter 2: Biological and Environmental Foundations

Question 1

Mitosis vs meiosis

Answer 1

• Mitosis - each cell has the same DNA as parents
• Meiosis - egg and sperm creation, different DNA between cells

Question 2

Fertilization

Answer 2

Sperm and egg fuse to form a zygote (46 chromosomes, 23 pairs)

Question 3

The ___ chromosome pair is the sex chromosome

Answer 3

23rd

Question 4

Types of twins

Answer 4

• Dizygotic - 2 zygotes, share 50% of DNA
• Monozygotic - one zygote, identical

Question 5

Types of genetic inheritance

Answer 5

Dominant-recessive, incomplete, polygenic, genomic imprinting

Question 6

Dominant-recessive inheritance

Answer 6

Dominant is always expressed unless there are two recessive genes

Question 7

Incomplete inheritance

Answer 7

Both genes influence, “blending”

Question 8

Polygenic inheritance

Answer 8

Interactions of many genes

Question 9

Genomic imprinting

Answer 9

Expression dependent on inheritance from mother or father

Question 10

Huntington’s disease

Answer 10

Develop normally until 40, then develop symptoms. A neurodegenerative disorder.

Question 11

Down syndrome

Answer 11

Additional chromosome on pair 21, leads to premature aging and decline of cognitive function. Associated with Alzheimer’s, developmental delays, change in facial shape.

Question 12

Mutations are often ____ and caused by…

Answer 12

Fatal, exposure to toxins or spontaneous

Question 13

Example of beneficial mutations

Answer 13

Sickle cell gene

Question 14

Four components of genetic counseling

Answer 14

Risk determination, family history of heritable disorders, genetic screening blood tests, determining how to proceed

Question 15

Examples of risk factors in reproduction

Answer 15

Women over 35, infertility

Question 16

Types of reproductive technology

Answer 16

Artificial insemination, in vitro fertilization, surrogacy, prenatal selection

Question 17

In vitro fertilization

Answer 17

Multiple eggs are harvested, but only one or two zygotes are transferred (50% survival rate)

Question 18

Ethical concerns of surrogacy

Answer 18

It’s hard to give the baby up, creates a power dynamic between the classes

Question 19

Types of prenatal selection

Answer 19

Pre-conception sperm sorting, pre-implantation genetic diagnosis

Question 20

Problems with adoption

Answer 20

Expensive, more common in upper class, often unhealthy foster care

Question 21

Methods of prenatal diagnosis

Answer 21

• Ultrasound
• Fetal MRI
• Noninvasive prenatal testing
• Amniocentesis
• Chorionic villus sampling

Question 22

Noninvasive prenatal testing

Answer 22

Take a blood sample from the mother

Question 23

Amniocentesis

Answer 23

Take a sample of amniotic fluid through the abdomen

Question 24

Chorionic villus sampling

Answer 24

Take a sample of the membrane around the amniotic fluid through the vagina

Question 25

Types of prenatal treatment

Answer 25

Fetoscopy, hormone and drug deliver, blood transfusions, surgical procedures, genetic engineering

Question 26

Fetoscopy

Answer 26

Small camera that goes through the abdomen

Question 27

Behavioral genetics

Answer 27

Heritability, family/twin studies, adoption studies

Question 28

Gene-environment interactions

Answer 28

Range of reaction, canalization, gene-environment correlations, epigenome

Question 29

Range of reaction

Answer 29

Range of a trait’s potential expression (ex. height), affected by environment

Question 30

Canalization

Answer 30

Traits that have a more narrow range of development (ex. eye color)

Question 31

Gene-environment correlations

Answer 31

Passive, reactive/evocative, active (niche-picking)

Question 32

Epigenome

Answer 32

Determines if and how genes are expressed