week 3 - blood types and genes

Question 1

biological male

Answer 1

individuals having the capacity/biological equipment to make small, mobile gametes: sperm

Question 2

biological female

Answer 2

individuals having the capacity/biological equipment to make large immobile gametes: eggs

Question 3

male heterogamety

Answer 3

when a male organism produces two different types of sex gametes

Question 4

female heterogamety

Answer 4

female produces two different sex chromosomes and male has two copies of the same chromosomes

Question 5

are all sex linked traits in the x chromosome?

Answer 5

yes

Question 6

what is a pedigree?

Answer 6

a chart that diagrams the inheritance of a trait or health condition through generations of a family
-shows up in the phenotype
-also helps us determine the alleles that individuals will carry and the likelihood that the offspring of two individuals will exhibit a particular trait

Question 7

how many sex chromosomes do we have?

Answer 7

one copy each of their sex chromosomes
-two copies of every chromosome in every cell (autosomal)

Question 8

heredity

Answer 8

the passing of characteristics from parents to offspring through their genes

Question 9

single gene traits

Answer 9

traits that are determined by the instructions a person carries on one gene
-ex. fur length or coat color in cats because some traits are determined by the instruction that an organism carries on one gene

Question 10

true breeding

Answer 10

when parents always produce offspring with the same variant of the trait as the parents

Question 11

segregation

Answer 11

you have two copies of each gene but each sperm or egg you produce has just one copy

Question 12

key to understanding dominant and recessive traits

Answer 12

a dominant trait masks the effect of a recessive trait when an individual carries both the dominant and the recessive versions of the instructions for the trait

Question 13

broken down law of segregation

Answer 13

1. one of two alleles for a gene is passed to a gamete. at fertilization, offspring receive one allele from each parent that codes for one gene
2. rather than passing on the trait itself, each parent puts into every sperm or egg it makes a single set of instructions for building the trait (called a gene)
3. offspring receive two copies of the instructions for any trait
4. trait observed in an individual depends on the two copies of the gene it inherits from its parents
   - same two alleles inherited = homozygous genotype
   - different two alleles inherited = heterozygous genotype
   - dominant and recessive alleles are defined by their action when they are in the heterozygous state

Question 14

phenotype

Answer 14

outward appearance and behavior of an individual
(ex. pigmentation, eye color)

Question 15

genotype

Answer 15

an organisms genetic composition (in reference to a particular trait)
-also used as a way of referring to all of the genes an individual carries

Question 16

sex linked traits

Answer 16

traits that are controlled by genes on the sex chromosomes
-recessive sex linked traits appear more frequently in males, and dominant sex linked traits appear more frequently in females

Question 17

how do you exhibit dominant traits?

Answer 17

all affected individuals must have at least one parent who exhibits the trait

Question 18

how can a recessive trait be exhibited?

Answer 18

may exhibit a recessive trait even if neither parent shows the trait
-individuals parents must be heterozygous for that trait
-unaffected parents can also have offspring with the disorder as a recessive trait

Question 19

genome

Answer 19

an organisms entire set of DNA
-

Question 20

when trait is autosomal dominant

Answer 20

• trait cannot skip generations
• shaded individuals are heterozygous dominant or homozygous dominant
  -unshaded individuals are homozygous recessive

Question 21

when trait is autosomal recessive

Answer 21

-shaded individuals are homozygous recessive
- unshaded individuals must be heterozygous
- can skip generations

Question 22

when trait is x linked dominant

Answer 22

affected daughters come from affected fathers

Question 23

when trait it x linked recessive

Answer 23

• if the female has it, that means that all of her sons will have it
• affected daughters come from affected fathers
• can skip generations
• males only need one copy to show the trait

Question 24

example of a pedigree

Question 25

example of degree of relatedness