Unit 5 : Heredity

Question 1

what is a trait

Answer 1

a specific characteristic of an organism.
- they can be determined by genes or environment
- they are passed down from parent to off spring

Question 2

what is heredity

Answer 2

passing of traits from parents to off spring

Question 3

what is genetics

Answer 3

study of heredity

Question 4

genetic inheritance occurs both in ____ and ____ reproduction

Answer 4

sexual + asexual

Question 5

who is gregor mendel

Answer 5

¨Father of genetics¨
- worked in the gardens and his experiments with peas showed that genes are discrete units that keep their separate identities when passed from generation to generation

Question 6

what are some characteristics of traits

Answer 6

• eye color
• leaf shape
• tail length
• widows peak

Question 7

what is a ¨ cross ¨

Answer 7

the mating of 2 organisms

Question 8

what are the 3 medels laws

Answer 8

1. Law of segregation
2. law of independent assortment
3. law of dominance

Question 9

what is the law of segregation

Answer 9

organisms inherit 2 copies of each gene, one from each parent/ when chromosomes separate in meiosis , each gamate will receive only one chromones from each pair

Question 10

what is a gene

Answer 10

peices of dna that provide instructions to make a certain protein
- genes determine traits

Question 11

what is an allele

Answer 11

diffrent versions of genes
- they can be homozygous or heterozygous

Question 12

what is a geneotype

Answer 12

refers to an organisms combination of alleles
ex BB, Bb, bb

Question 13

what is a phenotype

Answer 13

PHYSICAL characteristics
ex. blue eyes, brown fur, tall plant, smooth peas

Question 14

what is a dominant allele

Answer 14

the allele that is showed when 2 different allels are present
ex. AA or Aa

Question 15

what is the law of dominance

Answer 15

a dominant allele will express itself over a recessive allele
ex. Freckles (F) are dominant over non- freckles (f), if you get the big F then you’ll have freckles

Question 16

law of independent assortment

Answer 16

inheritance of one trait does not affect the inheritance of another

Question 17

what is a complex inheritance

Answer 17

not all traits that scientists predicted in test crosses Mendel’s law of inheritance

Question 18

what is incomplete dominance

Answer 18

dominant allele is not completly expressed when the recessive allele is around
- phenotype will be mixed
ex. Red flower + White flower = Pink flower

Question 19

what is codominance

Answer 19

alleles work toghther
both traits are fully expressed + separately
when organism has 2 different alleles it’ll express both at the same time

Question 20

what is polygenic traits

Answer 20

trait produced by 2 or more genes
shows a range in phenotype
ex. skin color, height , eye color

Question 21

what is multiple alleles

Answer 21

having more than 2 alleles for one gene
ex. blood type or bunny fur

Question 22

what are sex- linked taits

Answer 22

traits that are specifically on the sex chromosome
ex. color blindness or hemophilia

Question 23

what is one thing pedigrees can help with

Answer 23

can help determine probibility if offspring will inherit a genetic disorder

Question 24

affected ____ cannot pass it to their suns but can pass it to their daughters

Answer 24

males

Question 25

what is autosomal dominant

Answer 25

all affected individuals will have at lease 1 dominant allese
- both genders can be able to inherit
- wont skip generations

Question 26

what is autosomal recessive

Answer 26

all affected individuals will be homozygous recessive
- it skips generations and Is rare

Question 27

what is a mutation

Answer 27

changes in the nucleotide- base sequance of a gene or DNA molecule 1

Question 28

what is a germ cell mutation

Answer 28

occurs in an organsims gamates
- these typically don’t affect the organism itself
- these can be passed downf

Question 29

what is a somatic cell mutation

Answer 29

occurs in body cells of an organism
- these can affect the organism
- not inherited
ex skin cancer

Question 30

what is a gene mutation

Answer 30

produces a change within a single gene