Meiosis

Question 1

What are genetics?

Answer 1

The study of heredity and hereditary variation.

Question 2

what is heredity?

Answer 2

the transmission of traits from one generation to the next.

Question 3

what are some parts of asexual reproduction?

Answer 3

single individual, fusion of gametes, offsprings are exact copies of parent, mutations are the only source of variation, can produce asexually through mitosis.

Question 4

what are some parts of sexual reproduction?

Answer 4

two parents (male/female), offspring are unique combinations of genes from parents, genetically varied from parents and siblings.

Question 5

what are homologous chromosomes.

Answer 5

a pair of chromosomes that carry the same genetic information.

Question 6

where do you get homologous chromosomes from?

Answer 6

one from mom one from dad.

Question 7

whats a karyotype?

Answer 7

a display of chromosomes pairs ordered by size and length

Question 8

what are somatic cells?

Answer 8

diploid or 2n, two complete sets of each chromosome.

Question 9

what are gametic cells?

Answer 9

haploid or n one set of each chromosomes.

Question 10

in eukaryores where is DNA packaged?

Answer 10

in chromosomes

Question 11

what are the two types chromosomes

Answer 11

autosomes and sex chromosomes

Question 12

what are autosomes

Answer 12

chromosomes that do not determine sex (humans have 22 pairs)

Question 13

what are sex chromosomes?

Answer 13

X and Y
eggs: x (humans 22+x) sperm x or y (humans 22+x or 22+y)

Question 14

what is the life cycle?

Answer 14

sequence of stages in the reproductive history of an organism from ception to its own reproduction.

Question 15

how is a zygote formed and what is this called?

Answer 15

when a sperm cell fuses with an egg to form a zygote and this is called fertilization.

Question 16

what is meiosis?

Answer 16

a process that creates haploid gamete cells in sexually reproducing diploid organisms.

Question 17

what does meiosis result in?

Answer 17

daughter cells with half the number of chromosomes as the parent cells

Question 18

whats the difference between mitosis and meiosis?

Answer 18

Mitosis-Occurs in somatic cells
1 division
Results in 2 diploid daughter cells
Daughter cells are genetically identical
meiosis - Forms gametes (sperm/egg)
2 divisions
Results in 4 haploid daughter cells
Each daughter cell is genetically unique

Question 19

what are the three key events in meiosis that are unique?

Answer 19

prophase I, metaphase I and anaphase I.

Question 20

what happens in interphase?

Answer 20

cell goes through g1 S (dna is copied) and g2

Question 21

what happens in prophase I?

Answer 21

homologous chromosomes pair up and physically connect to form a tetrad.

Question 22

where does crossing over happen?

Answer 22

at the chiasmata

Question 23

what happens in metaphase I?

Answer 23

independant orientation, tetrads line up at the metaphase plate.

Question 24

what happens in anaphase I?

Answer 24

pairs of homologous chromosomes separate, sister chromatids are still attached.

Question 25

what happens telophase I and cytokinesis.

Answer 25

nuclei and cytoplasm divide, there is now a haploid set of chromosomes in each daughter cell.

Question 26

what happensi n telophase I and cytokenesis?

Answer 26

nuclei and cytoplasm divide, there is now a haploid set of chromosomes in each daughter cell.

Question 27

what happens in prophase II?

Answer 27

no crossing over, spindle forms.

Question 28

what happens in metaphase II?

Answer 28

chromosomes line up at the metaphase plate, because of crossing over in meiosis I the chromatids are unique.

Question 29

what happens in anaphase II?

Answer 29

sister chromatids seperate and move towards opposite poles.

Question 30

what happens in telophase II and cytokenesis?

Answer 30

4 haploid cells, nuclei reappear, each daughter cell is genetically unique.

Question 31

How does meiosis lead to genetic variation?

Answer 31

Crossing over (produces recombinant chromosomes they exchange genetic material). Independent assortment of chromosomes ( chromosomes are randomly oriented along the metaphase plate during metaphase I ) random fertilization (any sperm can fertiliaze any egg).

Question 32

what does DNA and RNA carry?

Answer 32

genetic information

Question 33

why did mendel experiment on pea plants?

Answer 33

many varieties, controlled mating and relatively short generation times.

Question 34

whats true breeding.

Answer 34

organisms that produce offspring of the same variety over many generations of self pollination.

Question 35

what is P generation

Answer 35

true breeding parental generation

Question 36

what is f1 generation?

Answer 36

offspring of the p generation

Question 37

what is is F2 generation

Answer 37

offspring of the f1 generation.

Question 38

what do testcrosses do?

Answer 38

they help determine if the trait is dominant heterozygous or homozygous.

Question 39

whats the law of segregation?

Answer 39

the two alleles for the same trait separate during gamete formation and end up in different gametes.

Question 40

are somatic cells haploid.

Answer 40

no diploid

Question 41

what do somatic cells contain.

Answer 41

two copies of each chromosome

Question 42

whats an allele?

Answer 42

alternative version of a gene.

Question 43

whats the law of independant assortment.

Answer 43

genes for one trait are not inherited with genes of another trait.

Question 44

what does the law of independant assortment apply to?

Answer 44

genes that are located on different chromosomes (not homologous) or genes that are very far apart on the same chromosome.

Question 45

what is the multiplication rule

Answer 45

the probability that two or more independent events will occur together in some specific combination