Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Topic six - Chromosomes to Genomes > Flashcards

Topic six - Chromosomes to Genomes Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Homologous Chromosomes and Sex Chromosomes

A

Homologous: Carry same genes at loci.
Autosomes: Non-sex chromosomes.
Sex Chromosomes: Determine gender (XX, XY).

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

Distinction: Genes, Alleles, Genome

A

Genes: DNA sequences for specific proteins.
Alleles: Variants of a gene.
Genome: Entire DNA content of an organism.

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

Chromosomes to Genomes

A

Chromosomes are structures containing genes.
Genes hold instructions for protein production.
A genome is an organism’s complete DNA set.

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

Karyotypes and Chromosome Abnormalities

A

Karyotypes show chromosome arrangement.
Aid identification of genetic disorders.

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

Meiosis and Genetic Diversity

A

Meiosis forms gametes from diploid cells.
Crossing over, independent assortment create diversity.

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

Eukaryotic Chromosome Structure

A

Eukaryotes: DNA packaged into chromosomes.
Composed of DNA and histones.
Nucleosome: DNA coils around histone core.
Nucleosomes combine to form supercoils.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Prokaryotic Chromosome Structure

A

Prokaryotes: Lack histones, circular chromosome.
Improper DNA packaging leads to genetic loss.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Prokaryotic Chromosome Structure

A

Prokaryotes: Lack histones, circular chromosome.
Improper DNA packaging leads to genetic loss.

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

What are chromosomes made up of, and where are they found?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are chromosomes made up of, and where are they found?

A

Chromosomes are made up of strings of genes and are found in the nucleus of living cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How do different genes contribute to the development of characteristics in an organism?

A

Different genes issue instructions to the cell for the development of different characteristics.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the role of a gene in an organism?

A

A gene contains instructions for producing proteins and functional RNA molecules that control specific traits or characteristics.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define “alleles.”

A

Alleles are different versions of the same gene that occupy the same position (locus) on homologous chromosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do alleles contribute to inherited variation?

A

Alleles are responsible for creating variations in traits between individuals within a population.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the locus of a gene?

A

The locus of a gene is its specific position on a chromosome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a homologous pair of chromosomes?

A

In sexually reproducing organisms, most cells have a homologous pair of chromosomes, with one chromosome from each parent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are alleles for a specific gene?

A

Alleles are different versions of the same gene that code for variants of the same polypeptide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does the term “genome” refer to?

A

A genome is the complete set of genetic instructions for an organism, encompassing its total DNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How is the genome of a eukaryotic zygote organized?

A

The genome of a eukaryotic zygote consists of 46 DNA chromosomes, arranged into 23 pairs, with one chromosome from each parent.

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

How is the size of an organism’s genome measured?

A

The size of an organism’s genome is determined by measuring the haploid (n) number of base pairs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What comprises the genome of a prokaryotic organism?

A

The genome of a prokaryotic organism consists of the DNA within its single circular chromosome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What constitutes the genomes of viruses and retroviruses?

A

The genomes of viruses and retroviruses consist of their entire genetic instructions encoded in one DNA or RNA molecule.

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

What are homologous chromosomes?

A

Homologous chromosomes are chromosomes that match in size and contain the same genes at the same loci.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How are chromosomes stained to aid in their identification?

A

Chromosomes are stained with Giemsa, producing dark bands in regions with high adenine and thymine concentrations, and light bands in regions with high cytosine and guanine concentrations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How are autosomes identified in humans?

A

Autosomes in humans are numbered from 1 to 22 in order of decreasing size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the role of the SRY gene in the Y chromosome?

A

The SRY gene codes for a protein that controls the development of male characteristics.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How are sex chromosomes separated during meiosis in males?

A

During meiosis in males, the X and Y chromosomes pair up during metaphase before being separated into daughter cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How many autosomes and sex chromosomes are there in humans?

A

Humans have 44 autosomes and 2 sex chromosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What happens during the S-phase of the cell cycle?

A

During the S-phase of the cell cycle, all the DNA inside the cell must replicate.

30
Q

What happens in prophase of the cell cycle?

A

During prophase, chromosomes condense and take on the familiar ‘X’ shape.

31
Q

What are sister chromatids?

A

Sister chromatids are the arms of the ‘X’-shaped chromosomes.

32
Q

What are p arms and q arms of chromosomes?

A

The shorter arms are called p arms, and the longer arms are called q arms.

33
Q

What are centromeres, and what is their role?

A

Centromeres are constriction points along the lengths of chromosomes where spindle fiber proteins attach during cell division.

34
Q

What is the significance of chromosome size differences?

A

Chromosome sizes vary across different organisms and indicate differences in the number of genes they contain.

35
Q

What is a locus?

A

A locus is the specific location where each gene is found on a chromosome.

36
Q

What is a karyotype, and how is it useful?

A

A karyotype is a visual representation of chromosomes, useful for identifying chromosome abnormalities and species differences.

37
Q

What is meiosis?

A

Meiosis is the process of forming gametes or sex cells, where a single cell divides twice to produce four daughter cells with reduced chromosome numbers.

38
Q

What is trisomy?

A

Trisomy occurs when there are three copies of a chromosome instead of the typical pair.

39
Q

What is monosomy?

A

Monosomy occurs when one member of the typical pair of chromosomes is missing.

40
Q

What is translocation in terms of chromosome changes?

A

Translocation is the alteration of a chromosome segment’s location, often involving a new region within the karyotype.

41
Q

How do parental origins of chromosomes affect development?

A

How do parental origins of chromosomes affect development?

42
Q

How many chromosomes do human somatic cells have?

A

Normal human somatic cells have 46 chromosomes.

43
Q

How many chromosomes do human gametes have?

A

Human gametes have 23 chromosomes.

44
Q

What is the purpose of meiosis?

A

Meiosis halves the chromosome number to produce gametes, leading to genetic diversity in offspring.

45
Q

How is variation achieved in meiosis?

A

Variation is achieved in meiosis through processes like crossing over and independent assortment.

46
Q

How is variation achieved in meiosis?

A

Variation is achieved in meiosis through processes like crossing over and independent assortment.

47
Q

How does meiosis differ from mitosis?

A

Meiosis results in the formation of haploid gametes with genetic diversity, while mitosis produces identical diploid cells.

48
Q

What is meiosis?

A

Meiosis is a cell division process that forms haploid gametes (sex cells) containing only one set of chromosomes.

49
Q

Why are gametes haploid?

A

Gametes are haploid to restore the diploid number of chromosomes upon fertilization, resulting in a zygote with two sets of chromosomes.

50
Q

How many stages are there in meiosis and what are they called?

A

Meiosis consists of nine stages, divided between Meiosis I and Meiosis II.

51
Q

What happens during crossing over?

A

Crossing over occurs during prophase I and ||of meiosis, where homologous chromosomes exchange parts, leading to new combinations of alleles.

52
Q

What is independent assortment?

A

Independent assortment is the random separation of pairs of alleles during meiosis, leading to various combinations of chromosomes in gametes.

53
Q

Meiosis I: Interphase

A

DNA in the cell is replicated, resulting in two identical full sets of chromosomes, each consisting of sister chromatids joined at the centromere.

54
Q

Meiosis I: Prophase I

A

The nuclear envelope disintegrates, chromosomes condense, spindle fibers appear, and crossing over between homologous chromosomes takes place

55
Q

Meiosis I: Metaphase I

A

Homologous chromosome pairs line up along the equator of the cell, with spindle fibers attaching to each chromosome.

56
Q

Meiosis I: Anaphase I

A

Homologous chromosomes are pulled to opposite poles of the cell by the meiotic spindle, resulting in separated chromosomes.

57
Q

Telophase I

A

Chromosomes gather at each pole, new nuclei form around them, and cytokinesis occurs, creating two daughter cells, each containing a full set of chromosomes.

58
Q

Meiosis II: Prophase II

A

Chromosomes condense again, the nuclear envelope dissolves, centrioles duplicate, and meiotic spindle forms.

59
Q

Meiosis II: Metaphase II

A

Sister chromatids of each chromosome line up along the equator of the cell, with spindle fibers attaching to each chromatid.

60
Q

Meiosis II: Anaphase II

A

Sister chromatids are pulled to opposite poles by the meiotic spindle, resulting in individual chromosomes.

61
Q

Meiosis II: Telophase II

A

Chromosomes gather at each pole, new nuclei form around them, cytokinesis occurs, and four haploid daughter cells are produced.

62
Q

What are the effects of chromosome nondisjunction?

A

Chromosome nondisjunction can lead to aneuploidy, where cells have an abnormal number of chromosomes, potentially causing genetic disorders such as Down syndrome, Turner syndrome, or Klinefelter syndrome.

63
Q

What is chromosome nondisjunction?

A

Chromosome nondisjunction is a failure of chromosomes to separate properly during cell division, resulting in an abnormal distribution of chromosomes in daughter cells.

64
Q

What is a metacentric chromosome?

A

A metacentric chromosome has its centromere positioned near the middle, resulting in two chromosome arms of approximately equal length.

65
Q

What is a submetacentric chromosome?

A

A submetacentric chromosome has its centromere toward one end, causing one chromosome arm to be shorter than the other.

66
Q

What is an acrocentric chromosome?

A

An acrocentric chromosome has its centromere near one end, leading to one very short chromosome arm (p arm) and one longer arm (q arm).

67
Q

What is a telocentric chromosome?

A

A telocentric chromosome has its centromere at or very near one end, resulting in a single chromosome arm extending from the centromere.

68
Q

What is Turner syndrome?

A

Turner syndrome is a genetic disorder in females where one of the X chromosomes is partially or completely missing, resulting in short stature, webbed neck, and other developmental and health issues.

69
Q

What is Klinefelter syndrome?

A

Klinefelter syndrome is a genetic condition in males where they have an extra X chromosome (XXY), leading to infertility, reduced testosterone levels, and potential physical and developmental differences.

70
Q

What is Edwards syndrome?

A

Edwards syndrome is a genetic disorder caused by the presence of an extra copy of chromosome 18, leading to severe developmental abnormalities and often resulting in a short lifespan for affected individuals.

Biology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions