Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BI157 > Chapter 13 > Flashcards

Chapter 13 Flashcards

(55 cards)

Start Studying
1
Q

What is hereditary?

A

transmission of traits from one generation to another

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

What is variation? (2)

A

reason identical copies from parents result in differences in offspring

the pheneotype

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

What are genetics? (2)

A

the scientific study of heredity and hereditary variation

the genotype

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

What are genes? (2)

A

hereditary units containing information/DNA

Programs cells to synthesize certain enzymes or proteins

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

What are gametes? (3)

A

reproductive cells that transmit genes

male gametes- sperm

female gametes- eggs

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

What is the locus?

A

gene’s specific location on a chromosome

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

What is asexual reproduction?

A

a single individual passes its genes without fusion of gametes

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

What is an example of asexual reproduction, and what does it result in?

A

Mitotic cell division

results with a clone (genetically identical individual)

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

What is sexual reproduction? (2)

A

two parents give rise to offspring with unique combinations of genes two parents

Vary genetically from siblings and parents

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

What is a life cycle?

A

sequence of stages in the reproductive history of an organism

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

What us a karyotype? (2)

A

pairs of chromosomes arranged from the longest

The two sets of 23 types of chromosomes are put together

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

What are homologous chromosomes/ homologs? (2)

A

pair of chromosomes with the same length, centromere position, and staining pattern

both pairs carry the same genes

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

What are human female chromosomes?

A

homologs of X chromosomes

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

What are human male chromosomes?

A

XY chromosomes

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

What are sex chromosomes, and what do they determine?

A

Human X and Y chromosomes

determines offspring’s sex

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

What are autosomes

A

non-sex chromosomes

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

What are diploid cells? (2)

A

cell with two sets of chromosomes (2n=46)

n= number of chromosomes in a single set

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

What are haploid cells? (2)

A

cells with only one set of chromosomes

In humans, the haploid number is 23

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

What is the human life cycle? (3)

A

Begins with fertilization, When a haploid sperm fuses with a haploid egg and fuses their nucleus

Forms a zygote- Diploid fertilized egg

As humans develop into sexually mature adults, mitosis of the zygote and its offspring generate somatic cells

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

How do gametes develop and reproduce? (4)

A

Only cells that do not produce through mitosis

Develop from germ cells in gonads

It cannot undergo mitosis if it does, it would become diploid

Undergoes meiosis

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

How is significant about gamete meiosis? (3)

A

Reduces the number of sets of chromosomes from two to one in gametes

Prevents doubling of chromosomes

Only diploid cells undergo meiosis

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

How do sexual life cycles vary?

A

Different species have different timing of fertilization and meiosis in their life cycle

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

What are the three groups of sexual life cycles?

Study These Flashcards
A

humans and most animals

alternation of generations

fungi, protists, and algae

24
Q

What is the sexual life cycle of humans and most animals? (2)

Study These Flashcards
A

gametes are the only haploid cells

Do not undergo further cell division other than meiosis prior to fertilization

25
What is alternation of generations? (2)
Exhibited by some algae and plants includes both a diploid and haploid stage
26
What occurs during the diploid stage in the alternation of generations? (5)
AKA sporophyte Produces haploids through miosis called spores Spores do not fuse, but divide mitotically, generating a haploid stage called gametophyte gametophyte gives rise to gametes by mitosis
27
What occurs during the haploid stage in the alternation of generations?
During fertilization, it results in a fusion of two haploid cells into a diploid zygote Zygote develops into next the next sporophyte generation
28
What occurs in the sexual life cycle of fungi, protists, and some algae? (4)
After gametes fuse and form a diploid zygote, meiosis occurs without a diploid offspring developing - Produces haploid cells instead of gametes Haploid cells divide by mitosis and give rise to a descendent The Descendent undergoes further mitosis to produce the cells that develop into gametes
29
What is meiosis? (3)
Consists of two consecutive cycles, Meiosis 1 and Meiosis 2 Results in four daughter cells, one chromatid each, with half the amount of chromosomes as the parents begins with a pair of sister chromatids, one from each parent
30
What occurs during Meiosis 1?
Reduction division (reduces the number of chromosomes)
31
What occurs during Prophase 1 early stage? (6)
Centrosome moves Spindle forms The nuclear envelope breaks down Chromosome condenses Chromosomes pair with their homolog cross over occurs
32
What is cross-over?
DNA molecules of chromatids are broken and rejoined with each other
33
What occurs during Prophase 1 middle stage?
Each pair has one or more x-shaped regions called chiasmata where crossover overs
34
What occurs during Prophase 1 late stage? (2)
Microtubules from one pole attach to the kinetochores Homologous pairs will move toward the metaphase plate
35
What occurs during Metaphase 1? (2)
Pairs of chromosomes are now on the plate Both chromatids are attached to kinetochore microtubules from one pole
36
What occurs during Anaphase 1? (3)
Proteins cleave sister chromatid cohesions along chromatid arms to separate Homologs move toward opposite poles Sister chromatid cohesion persists, causing chromatids to move as a unit
37
What occurs during Telophase 1? (3)
Each half of the cell has a complete haploid set of duplicated chromosomes Composed of two sister chromatids One or both chromatids include regions of non-sister chromatid DNA
38
What occurs during cytokinesis?
Occurs simultaneously with telophase, forming haploid daughter cells
39
What occurs during Meiosis 2?
Equational division- chromosomal number remains equal as haploid
40
What occurs during Prophase 2? (3)
Spindle forms each chromosome still consists of two chromatids moves towards metaphase 2 plate
41
What occurs during Metaphase 2? (3)
Chromosomes are positioned at the metaphase plate Because of crossover, chromatids are genetically different Kinetochores are attached to microtubules from opposite poles
42
What occurs during Anaphase 2? (2)
Proteins breakdown the cohesion of sister chromatids Chromatids move to opposite poles
43
What occurs during Telophase 2? (2)
Nuclei forms chromosomes decondenses
44
What is the result of meiosis? (2)
One parent cell produces four daughter cells with a haploid set of chromosomes All genetically distinct from parent and sibling cells
45
What occurs during the first step of crossover? (3)
During interphase, duplicated chromatids are held by cohesins Each homologous pairs are associated along their length DNA molecules get broken at corresponding points
46
What occurs during the second step of crossover? (3)
Synaptonemal complex forms - Zipperlike protein complex - Attaches homologs to each other
47
What occurs during the third step of crossover? (3)
Synaptonemal complex fully forms Homologs are in synapsis DNA breaks join to corresponding breaks, crossing over
48
What occurs during the fourth step of crossover? (3)
Synaptonemal complex disassembles Remains attached at cohesion Crossover locations show up as chiasmata
49
What is unique to meiosis when compared to mitosis? (3)
Synopsis and cross over Homologous pairs at metaphase Separation of homologs
50
How do the sister chromatids differ in mitosis and meiosis?
In mitosis, remain together until anaphase In meiosis, remain together until anaphase 2
51
Where does genetic variation arise during sexual reproduction? (3)
Independent assortment of chromosomes Crossing over Random fertilization
52
What is the independent assortment of chromosomes? (3)
Random orientation of homologous pairs at metaphase during meiosis 1 50% chance a daughter cell will get maternal chromosomes Independent assortment- maternal and paternal homologs sort independently from every other pair
53
How does crossing over result in genetic variation? (3)
Produces recombinant chromosomes Individual chromosomes carrying genes from different parents About 1-3 crossovers occur per pair
54
What is random fertilization?
The fusion of the male gamete and female gamete produces a zygote with trillions of diploid combination
55
How does genetic variation and evolution correlate? (2)
The population evolves from the reproductive success of its variants Sexual reproduction generated genetic diversity

BI157 (21 decks)

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