Genetics exam 1

Question 1

Mendel proposed that there are basic units of heredity passed from parent to offspring.

Answer 1

Particulate theory of inheritance

Question 2

Genes come in homologous pairs that segregate from each other into gametes, half carry one member of the pair and half carry the other.

Answer 2

Mendel’s first law of segregation

Question 3

G1- duplication, S- synthesis, G2- cell double checks for errors.

Answer 3

Interphase

Question 4

Connects the sister chromatids together in the middle.

Answer 4

Centromere

Question 5

Site on either side of sister chromatid where spindle fibers attach.

Answer 5

Kinetochore

Question 6

Reach out and bind to sister chromatids to pull them apart.

Answer 6

Spindle fibers

Question 7

Area between top and bottom of inner sister chromatids where tetrads form.

Answer 7

Synaptonemal complex.

Question 8

The attachment site that holds homologous chromosomes together after crossing over.

Answer 8

Chiasmata

Question 9

Kinetochores attach to microtubule from opposite spindle poles.

Answer 9

Mitosis and Meiosis II

Question 10

Sister chromatids segregate to the same spindle pole.

Answer 10

Meiosis I

Question 11

Segregation of sister chromatids results in-

Answer 11

Segregation of alleles.

Question 12

Cross between two heterozygotes

Answer 12

Monohybrid cross

Question 13

Cross between two individuals with two observed traits that are controlled by two distinct genes- from independent assortment.

Answer 13

Dihybrid

Question 14

Cross between a heterozygote for two genes and a recessive for all genes.

Answer 14

Testcross

Question 15

Take fraction of each individual and multiply them together to get a fraction of what the combined offspring between individuals would be.

Answer 15

Product rule

Question 16

Add probability of 1st and 2nd genotype.

Answer 16

Sum rule

Question 17

Doesn’t affect every generation, can inherit from unaffected parent, few generations affected.

Answer 17

Autosomal recessive

Question 18

Each generation is affected, M and F are affected, can be inherited from M or F, can inherit from unaffected parent.

Answer 18

Autosomal dominant

Question 19

Can be inherited from two unaffected parents, M affected more than F, sons can only inherit from mother; son can only inherit Y from dad.

Answer 19

X-linked recessive

Question 20

Daughters can only inherit from unaffected fathers, affected Aa females pass 1/2 to sons and 1/2 to daughters.

Answer 20

X-linked dominant

Question 21

Can only be passed from father to son, if Y carried allele with trait, they will be affected.

Answer 21

Y- linked

Question 22

Mitochondria and chloroplasts; mother to offspring only, never passed on by father.

Answer 22

Cytoplasmic inheritance

Question 23

During gamete formation, segregation of alleles, for one gene is independent of the segregation of alleles for other genes.

Answer 23

Mendel’s second law: law of independent assortment

Question 24

Attachment of spindle fibers to one tetrad does not affect the attachment of spindle fibers to other tetrads.

Answer 24

Allows chromosomes to assort independently.

Question 25

More than one gene influences a trait.

Answer 25

Polygenic inheritance

Question 26

Genes can be inherited in cytoplasmic organelles that are passed exclusively through eggs; show maternal inheritance.

Answer 26

Mitochondria and chloroplasts

Question 27

Unlinked chromosomes with genes A and B on different chromosomes will have results closer to the expected hypothesis. Unlinked chromosomes with genes A and B on the same chromosomes will have results further from expected hypothesis.

Answer 27

Genetic linkage

Question 28

When genes are further apart on a chromosome there will be a higher recombination frequency; on the linkage map the genes will be further apart.

Answer 28

Recombination (crossing over)

Question 29

A/a;B/b

Answer 29

unlinked

Question 30

AB/ab

Answer 30

linked

Question 31

Red+white=pink

Answer 31

Incomplete dominance

Question 32

Brown+gray=brown/gray speckles, blood typed IAIB =AB

Answer 32

Codominance

Question 33

Homozygous recessive die before birth, heterozygotes survive, and wild type survive.

Answer 33

Recessive lethal alleles

Question 34

One gene influences more than one trait

Answer 34

Pleiotropic

Question 35

An individual must have one dominant allele at both loci to display phenotype.

Answer 35

Complementation

Question 36

Percentage of individuals with a given genotype

Answer 36

Penetrance

Question 37

The extent to which a genotype is expressed at the phenotypic level.

Answer 37

Expressivity

Question 38

An individual with an allele for a trait may not develop the disease depending on the level that it's expressed due to expressivity.

Answer 38

How someone with allele doesn't develop disease.