Chapter 2.2 At the cellular level

Question 1

how do prokaryotic cells and unicellular eukaryotes reproduce

Answer 1

with cell division (mitosis)

Question 2

what are the highlight steps of cell division

Answer 2

1. DNA is replicated
2. Two copies of DNA are moved to opposite ends of cell
3. cell splits into two daughter cells

Question 3

where is DNA packaged into

Answer 3

chromosomes

Question 4

what differs between prokaryotes and eukaryotes in terms of DNA content

Answer 4

prokaryotes: one DNA molecule
eukaryotes: multiple linear chromosomes with lots of proteins

Question 5

what happens during cytokinesis

Answer 5

• division of cytoplasm
• one cell becomes two

Question 6

what is chromatin made of

Answer 6

DNA + proteins

Question 7

what are the 5 stages of mitosis

Answer 7

1. prophase
2. prometaphase
3. metaphase
4. anaphase
5. telophase

Question 8

cytokinesis in animal cells

Answer 8

• occurs by cleavage
• microfilaments contract until cell splits in two

Question 9

cytokinesis in plant cells

Answer 9

• cell plate produced by vesicles from golgi during telophase

Question 10

what is the cell cycle called in bacteria

Answer 10

Binary fission
- type of reproduction prokaryotes undergo
- cells grow to 2x its size then divides to make two cells

Question 11

what is a karyotype

Answer 11

• image of cell’s chromosomes laid out in pairs

Question 12

what is the locus

Answer 12

• gene’s specific location along length of a chromosome

Question 13

what are called the rest of the chromosomes that aren’t the sex chromosomes

Answer 13

autosomes

Question 14

Mitosis
- when does DNA replication occurs
- number of divisions
- synapsis of homologous chromosomes
- number of daughter cells and genetic composition
- role in the animal body

Answer 14

• occurs during interphase before mitosis
• only one division including prophase, prometaphase, metaphase, anaphase and telophase
• synapsis of homologous chromosome does not occur
• two daughter cells, each diploid and genetically identical to parent cell
• enables multicellular adult to grow from zygote, asexual reproduction in some species

Question 15

Meiosis
- when does DNA replication occurs
- number of divisions
- synapsis of homologous chromosomes
- number of daughter cells and genetic composition
- role in the animal body

Answer 15

• occurs during interphase before meiosis I begins
• two divisions each including prophase, metaphase, anaphase and telophase
• synapsis of homologous chromosomes occur during prophase I along with crossing over
• four daughter cells, each haploid containing half as many chromosomes as the parent cell; genetically different from the parent cell and from each other
• produces gametes, introduces genetic variability

Question 16

what do we call different versions of genes created by mutations

Answer 16

alleles

Question 17

what are the 3 different processes responsible for genetic variation

Answer 17

1. independent assortment of chromosomes
2. crossing over
3. random fertilization

Question 18

when does independent assortment occurs

Answer 18

during metaphase of meiosis I