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Flashcards in Genetics Deck (21):
1

What are the four phases of Mitosis?

Prophase, Metaphase, Anaphase, Telophase

2

What is a sister chromatid?

two identical chromosomes joined at centromere

3

What are homologous pairs?

equivalent but non identical and don't come near each other during mitosis

4

What happens during prophase?

Chromosomes condense, nucleolus disappears, spindle and kinetochore fibers appear, and centriole pairs move to opposite ends of cell.

5

What happens during metaphase?

chromosomes line up at center of cell.

6

What happens during Anaphase?

Spindle fibers shorten and sister chromatid pairs are pulled apart. Cell elonges and cleavage furrow formed

7

What happens during telophase?

nuclear membrane forms around chromosomes at each end of cell, nucleolus becomes visible. Cell splits in two

8

How many reading frames does a chromosome have?

three

9

What are the three reading frames?

Centromere, promoter, and regions of replication

10

What are protooncogenes

normal versions of genes thatallow for regular growth patterns but can be converted to oncogenes

11

What is a locus?

Specific location of gene on chromosome

12

What are alleles?

different versions of gene

13

What is a heterozygote?

a person carrying two different alleles at a given locus

14

What is a homozygote?

individual carrying two identical alleles

15

What happens during Prophase I of Meiosis?

homologs pair and recombination occurs

16

What happens in Metaphase I of Meiosis?

Tetrads are aligned on metaphase plate

17

What happens during Anaphase I of Meiosis?

Homologs separate. Sister Chromatids stay together

18

Describe Telophase I of Meiosis

Two haploid cells are made. Each cell has single set of chromosomes which exist as sister chromatids

19

What is the purpose of Meiosis II?

Just to separate sister chromatids

20

When are sister chromatids not identical?

Anaphase II

21

What is a testcross?

a cross with a homozygous recessive.