Week 2

Question 1

How many chromosomes are in most cells in the body

Answer 1

46

Question 2

What cells do not have 46 chromosomes? and how many do these cells have?

Answer 2

Egg and sperms cells
23

Question 3

What is the smallest unit of biochemical instruction in the DNA

Answer 3

gene

Question 4

how many genes in 46 chromosomes

Answer 4

25,000

Question 5

what percent of genes accounts for individual differences

Answer 5

less than 1%

Question 6

Which chromosome determines sex

Answer 6

the 23rd

Question 7

How does the inheritance of sex chromosomes work

Answer 7

males have XY, females XX
-you will inherit X from the mom and either for the dad
-dad determines gender of offspring

Question 8

Genotype

Answer 8

Sum of all the genes a person inherits

Question 9

Allele

Answer 9

different versions of a gene
-each person has 2 alleles per gene

Question 10

Phenotype

Answer 10

Features that are actually expressed

Question 11

Examples of single gene inheritance

Answer 11

-curly vs straight hair
-full head of hair vs baldness
-cheek dimples vs no dimples
-normal color vision vs red-green blindness
-type A vs type B vs type O

Question 12

Sickle-Cell disease

Answer 12

Red blood cells are sickle-shaped
-cells cannot pass through small capillaries
-causes fatigue, acute pain, prone to infections
-10% die by age 20 and 50% by age 50
Allele is recessive
-heterogenous individuals will experience symptoms only under trama

Question 13

Down Syndrome

Answer 13

DISTINIT PHYSICAL FEATURES
-almond eyes, fold over eyelids, smaller head, neck and nose
MENTAL & BEHAVIORAL DEVELOPMENT LAGS
MOTOR & MENTAL DEVELOPMENT SUBSTANTIALLY DELAYED IN CHILDHOOD

Question 14

Def: Evolution

Answer 14

process of change in gene frequencies over many generations
-acts to select heritable traits that are adaptive
-changes occur to the species over generations
-evolution does not act on individuals

Question 15

Natural selection

Answer 15

traits best adapted to current environment will be selected

Question 16

Polygenic inheritance

Answer 16

-psychological traits are manifested through the activities of many genes and their interactions with the environment
- results is several possible genotypes and many distinct phenotypes
-results in a normal distribution of phenotypes

Question 17

Evolutionary Theory of Development

Answer 17

-selected traits are adaptive for each stage of development

Question 18

Genotype x Phenotype

Answer 18

Most psychological traits are governed by many genes
-phenotype depends on a combination of genes, but also an interaction with the environment
-genotype cannot change; phenotype can

Question 19

Heritability

Answer 19

the extent to which differences in a trait can be attributed to inheritance
-a value of 0 to 1
-population level
-greater variability in environment = less heritability

Question 20

Monozygotic twins

Answer 20

identical twins
-one zygote
-splits in first 2 weeks

Question 21

Dizygotic Twins

Answer 21

fraternal twins
-two fertilized eggs develop in the uterus at the same time