Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIOL 107 > Chapter 7: The Cellular Basis of Inheritance > Flashcards

Chapter 7: The Cellular Basis of Inheritance Flashcards

1
Q

define asexual reproduction

A
  • produces genetically identical offspring
  • binary fission, mitosis, budding, cloning, etc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

define sexual reproduction

A
  • produces genetically different offspring
  • meiosis and fertilization: production and fusion of haploid cells into single diploid cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

define diploid life cycle

A
  • haploid gametes undergo fertilization to create diploid zygote
  • zygote undergoes mitosis to grow
  • meiosis creates haploid gametes from diploid cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

advantages of asexual reproduction

A
  • faster
  • no mate needed
  • population size increases rapidly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how does asexual reproduction introduce genetic variation

A

mutations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

disadvantages of asexual reproduction

A
  • no genetic variation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

why do most eukaryotes reproduce sexually

A
  • evolutionary success
  • advantage of genetic variation outweighs all disadvantages
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

advantages of sexual reproduction

A
  • genetic variation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how does sexual reproduction introduce genetic variation

A
  • mutations
  • meiosis: shuffling of genetic information
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

disadvantages of sexual reproduction

A
  • requires mate
  • energy spent in the process
  • only 1/2 of the population is capable of producing offspring
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the 4 main differences between mitosis and meiosis

A
  • number of divisions: mitosis=1, meiosis=2
  • number of cells and their ploidy: mitosis=2 diploid, meiosis=4 haploid
  • genetics: mitosis=genetically identical, meiosis=genetically unique
  • type of cell: mitosis=somatic, meiosis=sex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

describe the level of organization of a genome

A
  • DNA makes genes
  • genes make chromosomes
  • chromosomes make a genome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

define autosomes

A
  • all except sex chromosomes
  • homologous pairs: one similar chromosome from each parent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

define sex chromosomes

A
  • determines biological sex of individual
  • heterologous chromosomes: differ in shape and organization
  • X and Y in humans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

define allele

A
  • different variations of the same gene
  • more than 2 alleles often exist for 1 gene
  • creates genetic variation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

do X and Y chromosomes share any similar regions

A
  • yes
  • pseudo autosomal regions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

define ploidy

A
  • measure of number of sets of chromosomes
  • diploid: 2 sets (somatic cells)
  • haploid: 1 set (gametes)
  • polyploid: more than 2 sets (common in plants)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

describe the ploidy of human somatic cells and gametes

A
  • somatic cells: diploid, 2 sets of chromosomes (one from each parent), 46 chromosomes
  • gametes: haploid, 1 set of chromosomes, 23 chromosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what ploidy do most animal cells have

A

diploid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what animals are haploid

A
  • very rare
  • male bees
  • wasps
  • ants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what animals are polyploid

A
  • 2 species of birds
  • 1 species of rat
  • most common in insects, crustaceans, fish, reptiles, and amphibians
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

is there a correlation between genome number and organism complexity

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

do all animals have the same number of chromosomes

A
  • no
  • chromosome number is characteristic of a particular species
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

can species with different diploid numbers interbreed

A
  • unlikely
  • if they can the offspring are usually infertile due to uneven chromosome numbers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
example of interbreeding species
- horse and donkey breed and produce a mule - mule is infertile - horse: 2n=64 - donkey: 2n=62 - mule: 2n=63 --> cannot form functional gametes
26
describe interphase in meiosis
- same as mitosis - has G1, S, and G2 phase - S phase replicates chromosomes and creates identical sister chromatids
27
what does meiosis result in
- reduction of chromosome number - produces 4 haploid gametes: have single set of chromosomes
28
which part of meiosis do homologous chromosomes separate
meiosis 1
29
which part of meiosis do sister chromatids separate
meiosis 2
30
which part of meiosis reduces the cell from diploid to haploid
meiosis 1
31
explain prophase 1
- chromosomes condense and pair up - synapsis: each chromosome aligns with its homologous partner so corresponding positions along chromosome are matching - crossing over: homologues exchange part of their DNA
32
explain the process of crossing over in prophase 1
- homologous chromosomes pair up - synaptonemal complex holds them together in synapsis: physical connection of chromosomes - segments are exchanged through crossing over
33
what does the process of crossing over result in
- exchange of genetic information - recombinant chromosomes: carry genes from two parents
34
what is the physical point where homologues are connected during crossing over in prophase 1 called
chiasmata
35
during which step in meiosis does crossing over occur
prophase 1
36
what is the group of 2 homologous pairs of chromosomes during meiosis 1 called
tetrad
37
explain prometaphase 1
- spindle fiber microtubules attach to the kinetochore proteins at the centromeres - homologs still held together at chiasmata - nuclear membrane completely broken down
38
explain metaphase 1
- spindles attached to chromosomes - chromosomes line up in the center of the cell along the metaphase plate - independent assortment of chromosomes along metaphase plate
39
define independent assortment in meiosis
- sister chromatids separate without influence from another chromosome - random assortment of chromosomes (maternal and paternal) along metaphase plate during metaphase 1
40
during which phase of meiosis does independent assortment take place
metaphase 1
41
explain anaphase 1
- microtubules pull tetrads apart - homologous pairs move toward opposite poles of the cell - tetrads separate as chiasmata is broken but sister chromatids remain attached at the centromeres
42
define telophase 1
- separated chromosomes arrive at opposite poles - nuclear membrane sometimes reforms and chromosomes decondense (depends on organism)
43
what is the result of meiosis 1
two haploid cells
44
explain meiosis 2
- division of sister chromatids - very similar to mitotic division except sister chromatids are not genetically identical and resulting cells are haploid
45
what are the products of meiosis 2
- 4 haploid cells - genetically unique
46
what are the two types of chromosome abnormalities
- disorders in chromosome number - structural rearrangement of chromosomes
47
are chromosomes abnormalities typically severe or mild
- severe - fatal - result in miscarriages
48
define karyotype
- number and appearance of chromosomes - length, banding pattern, centromere position
49
define nondisjunction
- occurs when pairs of homologous chromosomes or sister chromatids fail to separate during meiosis - results in duplication or loss of chromosome
50
if there is nondisjunction during meiosis 1, how will the final cells be affected
- all will be affected - 2 will have extra chromosome - 2 will have one less chromosome
51
if there is nondisjunction during meiosis 2, how will the final cells be affected
- 2 cells will be affected - 1 will have extra chromosome - 1 will have one less chromosome - 2 will be unaffected
52
define euploid
individuals with the appropriate number of chromosomes
53
define aneuploid
- individual with an error in chromosome number - includes monosomy and trisomy
54
define monosomy
- loss of one chromosome - lethal for all autosomes
55
define trisomy
- gain of extra chromosome - most are lethal, some are not
56
describe x inactivation
- in each cell only one x chromosome is activated (only traits on that chromosome are expressed) - tortoiseshell cats fur color - allows nondisjunction with extra x chromosome to be less fatal
57
describe triple x syndrome
- XXX - females with three x chromosomes - 1 in 1000 births - 90% undiagnosed due to x silencing/inactivation
58
symptoms of triple x syndrome
- taller than average - increased risk of learning disabilities - weak muscle tone - behavioral and emotional difficulties - cardiovascular and reproductive issues
59
describe turner's syndrome
- X0 - females with only 1 x chromosome - 1 in 2500 births - more severe than triple x syndrome (95% don't survive to birth)
60
symptoms of turner's syndrome
- heart and kidney issues - short stature - webbing of neck - infertility
61
describe kleinfelter syndrome
- XXY - male with extra x chromosome - 75% undiagnosed - usually diagnosed when seeking medical advice for infertility issues - can be treated with testosterone therapy
62
symptoms of kleinfelter syndrome
- infertility - sparse facial hair - enlarged breasts - small testicles - narrow shoulders
63
describe jacob's syndrome
- XYY - male with extra y chromosome - 1 in 1000 males affected - often diagnosed along with autism
64
symptoms of jacob's syndrome
- attention difficulties - delayed motor skills - involuntary muscle movement - emotional or behavioral issues - taller than average - prone to acne and skin irritation
65
what are the 4 types of chromosome structural rearrangements
- duplications - deletions - inversions - translocations
66
explain chromosome duplications
- extra copy of a small piece of a chromosome - ex: potocki-lupski syndrome
67
explain chromosome deletions
- deletion of segment of a chromosome - ex: cri-du-chat
68
explain chromosome inversions
- detachment, 180-degree rotation, and reinsertion of part of a chromosome - changes orientation of gene - usually mild unless gene sequence is interrupted during detachment
69
explain chromosome translocations
- segment of chromosome breaks off and reattaches to different chromosome - can be benign or devastating - can be reciprocal: two non-homologous chromosomes exchange genetic information, no loss or gain of genetic information

BIOL 107 (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions