Exam 1: Lecture 2

Question 1

gene

Answer 1

distinct seq of nucleotides forming part of a chromosome; unit of heredity that is transferred from parent to offspring

Question 2

allele

Answer 2

one of two/more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome

Question 3

chromosome

Answer 3

threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carries genetic info in the form of genes

Question 4

genome

Answer 4

complete set of DNA, including all of its genes

Question 5

germplasm theory

Answer 5

inheritance in a multicellular organism only takes place by means of the germ cells ONLY

Question 6

characteristics of a prokaryote

Answer 6

• circular DNA (protects ends from nucleases and small amt)
• single cell
• nucleus absent
• no mem bound organelles!

Question 7

characteristics of eukaryotes (uni and multicellular)

Answer 7

• membrane bound organelles! i.e. mito!!
• chromosomes composed on DNA (multiple linear DNA molecules and lrg amt)
• proteins (histones) and functional units

Question 8

prok DNA arrangement? who is considered a prok?

Answer 8

disordered DNA and made up of eubacteria and archaea

Question 9

what are viruses

Answer 9

DNA/RNA stored inside a protein coat; has enough info to hijack another cell

Question 10

what is a homologous chromosome?

Answer 10

2 copies of a chromosome, not identical; each homolog carries the same genes in the same order, bu alleles for each trait may be diff

Question 11

diploid cells

Answer 11

carry two sets of genetic info

Question 12

haploid cells

Answer 12

carry one set of genetic info

Question 13

centromere

Answer 13

attachment point for spindle microtubules; kinetochores form and the spindle microtubules attach (tubulin)

Question 14

telomere

Answer 14

tips of a linear chromosome; stable ends of chromosomes

Question 15

submetacentric

Answer 15

short arms

Question 16

metacentric

Answer 16

centromere in the middle

Question 17

telocentric

Answer 17

almost no short arm; no genes

Question 18

acrocentric

Answer 18

centromere near the end producing a short arm ex chromosome 21 and 22

Question 19

interphase

Answer 19

extended period between cell divisions, DNA synthesis, and chromosome replication stage

G1, S, G2; G1/S and G2/M checkpoints

Question 20

mitosis

Answer 20

separation of sister chromatids; PMAT

Question 21

cytokinesis

Answer 21

separation of cytoplasm

Question 22

the number of chromosomes per cell =

Answer 22

the number of functional centromeres

Question 23

meiosis

Answer 23

production of haploid gametes

Question 24

fertilization

Answer 24

fusion of haploid gametes

Question 25

genetic variation

Answer 25

conseq of meiosis

Question 26

meiosis I

Answer 26

Meiosis I is separation of homologous chromosome pairs, and reduction of the chromosome number by half

Question 27

meiosis II

Answer 27

Meiosis II is separation of sister chromatids, aka equational division

Question 28

microtubules lengthen and shorten at

Answer 28

both the pos and neg ends

Question 29

homologous chromosomes

Answer 29

similar but not identical; each homolog carries the same genes in the same order, but the alleles for each trait may not be the same

Question 30

chromatid

Answer 30

either of 2 daughter strands of a duplicated chromosome; separate during cell division to become individual chromosomes

Question 31

prophase I of meiosis I: what occurs during this phase?

Answer 31

synapsis tetrad crossing over

Question 32

synapsis

Answer 32

prophase I; close pairing of homologous chromosomes

Question 33

tetrad

Answer 33

prophase I; closely associated four-sister chromosomes of 2 homologous chromosomes

Question 34

crossing over:

Answer 34

prophase I; exchange of genetic info, the first mechanism that generates genetic variation in newly formed gametes

Question 35

metaphase I

Answer 35

random alignment of homologous pairs of chromosomes along the metaphase plate

Question 36

anaphase I:

Answer 36

separation of homologous pairs and random distribution; second mechanism of generating genetic variation in newly formed gametes

Question 37

telophase I

Answer 37

cytoplasm divides and chromosomes at opp poles

Question 38

interkinesis

Answer 38

spindle breaks down, chromosomes relax, and nuclear envelope re-forms; no DNA synthesis