Bio 1610 Test 3 Chapter 13

Front 1

Asexual Reproduction

Back 1

Don't form gametes; reproduce mitotically

Front 2

What does mutation provide

Back 2

variability

Front 3

How do redwood trees reproduce

Back 3

They are all one organism until the parent dies then they become their own organism

Front 4

Sexual Reproduction

Back 4

2 parents; unique combination of genes in gametes

Front 5

Why are egg cells the largest cells by far

Back 5

They have to pack all the nutrients needed for the would-be fetus

Front 6

Why are sperm cells so teeny

Back 6

They only have one purpose and they die so they don't need all the organelles

Front 7

genetics

Back 7

the scientific study of heredity

Front 8

gene

Back 8

a unit of hereditary information consisting of a specific nucleotide sequence (DNA) -- segment of a chromosome

Front 9

Locus

Back 9

a specific place along a chromosome where a given gene is located (gene is on a locus, locus isn't on a gene)

Front 10

Clone

Back 10

A lineage of genetically identical individuals (not sexual form of reproduction)

Front 11

karyotype

Back 11

A display of chromosome pairs of a cell arranged by size and shape

Front 12

homologous chromosome

Back 12

a pair of chromosomes at the same length and with the same genes--one inherited from each parent

Front 13

Diploid cell

Back 13

a cell containing two sets of chromosomes (2n), 1 from each parent

Front 14

Haploid cell

Back 14

a cell containing only one set of chromosomes (1n)

Front 15

autosome

Back 15

a chromosome that is not a sex chromosome

Front 16

sex chromosome

Back 16

a chromosome that is responsible for determining the sex of the human

Front 17

fertilization

Back 17

the union of haploid cells to create a diploid zygote

Front 18

zygote

Back 18

a diploid cell produced by fertilization

Front 19

meiosis

Back 19

a reduction-cell division

consists of two rounds of cell division but only one round of DNA division

Front 20

Memorize the back

Back 20

In humans, meiosis 1 starts with 23 homologous pairs (46 chromosomes total) and end with 23 individual chromosomes.

Meiosis ends with haploid germ cells called egg and sperm.

There is no interphase in meiosis.

Front 21

what is the spindle called in meiosis

Back 21

spindle apparatus

Front 22

What do the chromosomes do in the beginning of M1

Back 22

Only 23 chromosomes line up because the male and female chromosomes pair and and cross over

Front 23

When does all crossing over occur

Back 23

first phase of meiosis

(prophase 1 --> metaphase)

Front 24

what are the steps to meiosis 1

Back 24

prophase 1, metaphase 1, anaphase 1, telophase + cytokenesis

Front 25

What is happening in meiosis 1

Back 25

Seperation of homologous chromosomes

Front 26

What is happening in meiosis 2

Back 26

Seperation of sister chromatids

Front 27

What are the steps in meiosis 2

Back 27

Prophase 2, Metaphase 2, Anaphase 2, Telophase 2 + cytokenesis

Front 28

explain what is happening in prophase 1

Back 28

begins by crossing over, DNA is being condensed

Front 29

Explain what is happening in metaphase 1

Back 29

homologous chromosomes are lined up at metaphase plate; both chromatids of one homolog are attached to the kinetichore microtubules of one pole while the other homolog chromatids are attached to the other

Front 30

Chiasmata

Back 30

Where the crossing over occurs

Front 31

Explain what is happening in anaphase 1

Back 31

Homologs seperate and move towards opposite poles

Front 32

Explain what is happening in telophase 1 and cytokenesis

Back 32

each half of the cell starts with a complete set of haploid cells

cytokenesis happens simultaneously with telophase forming two haploid daughter cells

Cleavage furrow begins to form

Front 33

explain what is happening in prophase 2

Back 33

spindle apparatus forms

Front 34

explain what is happening in metaphase 2

Back 34

chromosomes positioned at metaphase plate

(because of crossing over, two sister chromatids of each chromosome are not identical)

kinetochores of sister chromatids are attached to microtubules extending from opposite poles

Front 35

explain what is happening in anaphase 2

Back 35

sister chromatids seperate and move towards opposite poles as individual chromosomes

Front 36

explain what is happening in telophase 2 and cytokenesis

Back 36

nuclei form and chromosome begins decondensing and cytokenesis occurs

Front 37

What does the meitotic division of a parent cell produce

Back 37

four daughter cells, each with a haploid set of unduplicated chromosomes

the four daughter cells are genetically distinct from one another and from the parent cell

Front 38

Differences between mitosis and meiosis

Back 38

mitosis breaks the chromosome sets from diploid to haploid cells while meiosis conserves the number of chromosome sets thus resulting in genetic variation while mitosis produces cells that are genetically identical.

mitosis happens in haploid and diploid cells while meiosis only happens in diploid cells.

Front 39

Things that occur in meiosis that don't in mitosis

Back 39

synapsis and crossing over; homologous pairs line up at the metaphase plate rather than individual chromosomes

Front 40

what are sister chromatids held together by

Back 40

cohesins

Front 41

what is the synaptonemal complex

Back 41

basically zipper-like proteins that bring the mom and dad chromosomes together

Front 42

synapsis

Back 42

when the mom and dad chromosomes are fully joined together and ready for crossing over

Front 43

crossing over

Back 43

when two chromosomes are brought together and two sister chromatids break from each and the broken ends join with the sister chromatid of the other chromosome

Front 44

just remember interphase starts before meiosis where the chromosomes duplicate -- part of mitosis

Back 44

seriously, remember it