Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology 1000 > Unit 8-Cell Division > Flashcards

Unit 8-Cell Division Flashcards

(86 cards)

Start Studying
1
Q

Define cell division

A

Reproduction of a cell that results in two daughter cells that are genetically identical to each other and to the original parent cell

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

What are chromosomes

A

The structures that contain most of the cells DNA

It is split into two during cell division.

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

Define asexual reproduction

A

The creation of genetically identical offspring by a single parent without the participation of sperm and egg

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

Define sexual reproduction

A

It requires fertilization of an egg by a sperm
The production of gametes involves a special type of cell division that occurs only in reproductive organs
Offspring resemble parents but not identical

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

Define mitosis

A

One mother cell producing two daughter cells
Genetically identical
Same number of chromosomes
Happens in all eukaryotes

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

Define meiosis

A 
One mother cell divides into 4 products 
Genetically unique 
Half as many chromosomes
Happens only in specialized structures of certain eukaryotes 
Produces spores eggs or sperm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the three functions of cell division

A

Reproduction
Growth
Repair

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

Explain DNA organization

A

Chromosomes (X)
The coiled fibres are chromatin
DNA is wrapped around a Histone

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

How do prokaryotes reproduce

A

Binary fission

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

What is binary fission

What type of reproduction is it

A

Cell divides in half

Asexual

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

What are sister chromatids and what are they held together by

A

Duplicated chromosomes which contain identical copies of the DNA molecule
Held together by the centromere

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

When does a chromosome consist of two identical chromatids

A

When the cell is preparing to divide and has duplicated its chromosomes but before the duplicates actually separate

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

Explain the cell cycle

A

An ordered sequence of events that extends from the time a cell is first formed from a dividing parent cell until its own division into two cells

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

How is the DNA packaged in a working cell (interphase)

A

Chromatin

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

How is DNA packaged during cell division (M phase)

A

Chromosomes

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

Define interphase

A 
What most of the cell cycle consists of 
Cells metabolic activity is high and the cell preforms various functions 
Periods of growth
DNA replication
Preparation for mitosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Define the mitotic phase (M phase)

A

The part of the cell cycle when the cell actually divides

Nuclear division

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

Define cytokinesis

A

Begins before mitosis ends
The cytoplasm is divided in two
Cell division

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

Explain the stages of interphase

A

G1
-organelle expansion and cell growth
S phase
- DNA synthesis when chromosomes duplicate
G2
- mitochondria and chloroplasts growth centrosome divides
G0
- typical cell functions; respiration working and moving

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

What do we start with in mitosis

A

One cell with one nucleus

Two copies of each chromosome (chromatids)

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

What do we end with in mitosis

A

Two nuclei

Each with one copy of each chromosome

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

Where are the chromosomes during mitosis

A

In the nucleus

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

Where are the centrosomes during mitosis

A

In cytoplasm

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

Explain prophase

A

The chromatin fibres become more tightly coiled into chromosomes as sister chromatids
The mitotic spindles begins to form from the centrosomes
Centrosomes move away from each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Explain pro-metaphase
The nuclear envelop breaks into fragments and disappears Microtubules and centrosomes move to opposite poles and the mitotic spindles reach for the chromosomes Mitotic spindles attach to kinetochore
26
Explain metaphase
Mitotic spindles are attached to chromosomes and they are moved to the centre or metaphase plate
27
Explain anaphase
The two centromeres of each chromosome come apart separating the sister chromatids Move to each pole with an equivalent and complete set of chromosomes
28
Explain telophase
The cell continues to elongates Daughter nuclei appear at the two poles Nuclear envelope begins to form around chromosomes Chromatin uncoils from the chromosome shape and mitotic spindles disappear
29
Explain cytokinesis
The division of the cytoplasm | When the two daughter cells completely separate
30
Define the cleavage furrow
A shallow indentation in the cell surface | Happens in animal cells
31
Define cell plate
A membranous disc Grows outward Happens in plants
32
What happens when cytokinesis doesn't occur
Results in a bigger cell with two identical nuclei Yellow slime mould and muscle cells- lives as large multinuclei complexes
33
Define syncytium
Organisms that live as a very large cell containing multiple nuclei
34
Define the cell cycle control system
A cyclically operating set of molecules in the cell that both triggers and coordinates key events in the cell cycle
35
Checkpoints in cell cycles
A critical control point where stop and go signals can regulate the cycle
36
What checkpoint in the cell cycle is seen as the most important
G1 checkpoint Because if given go ahead it goes into cell division stages but if not then it goes into G0 where the cell doesn't divide
37
What are the requirements of the G1 checkpoint
Is the cell large enough Does the cell have enough nutrients Is the DNA undamaged Have the growth factors signalled
38
What are the requirements of the G2 checkpoint
Before the M phase | Must have successful DNA replication and undamaged DNA
39
What are the requirements of the metaphase checkpoint
Happens before anaphase Spindle fibres have to attach and ensure equal distribution
40
What is a tumour
An abnormally growing mass of body cells
41
Define benign tumours
When abnormal cells remain at the original site (are contained) Can cause problems if they grow in and disrupt certain organs
42
Define malignant tumours
Can spread into neighbouring tissues (cancerous)
43
Define metastasis
The spread of cancer cells beyond their original site
44
How are chromosomes arranged in meiosis
As homologous pairs
45
Define homologous pairs
Two matching chromosomes | Same genes but maybe in different forms
46
Define the locus
The particular place a gene is located to code for a specific trait such as freckles and is found on the chromosome
47
How many chromosomes in humans | How many pairs of chromosomes in humans
46 | 23
48
Are all of your chromosomes fully homologous
If you are a female then yes If you are a male then no - your sex chromosomes are only partly homologous
49
Define sex chromosomes | Define autosomes
The chromosomes that determines an individuals sex The other 22 pairs of chromosomes are called autosomes
50
Define somatic cells
Body cells
51
Are somatic cells diploid or haploid
Diploid cells 2N Two complete sets Homologous pairs Two copies of each gene
52
Are sex cells haploid or diploid
Haploid 1N Half as many chromosomes One copy of each gene
53
A fertilized egg is called what
A zygote
54
Is a zygote haploid or diploid
Diploid Has two sets of chromosomes One set from each parent
55
Define meiosis
A type of cell division that produces haploid cells in diploid organisms If it weren't for meiosis each generation would have twice as much genetic material as the generation before
56
explain interphase during meiosis
similar to mitosis; at the end of interphase each chromosome consists of two genetically identical sister chromatids and the centrosome also duplicates
57
explain prophase 1
chromatin coils up to form chromosomes synapsis occurs which is when homologous chromosomes come together into pairs which is called a tetrad crossing over occurs centromeres move apart spindle fibres produce and nuclear envelope dissolves
58
explain metaphase 1
chromosome tetrads align in the center | homologous chromosomes are linked together by crossing over
59
explain anaphase 1
the chromosomes move towards the two poles | the sister chromatids stick together and only the homologous chromosomes split and move across
60
explain telophase 1
the chromosomes arrive at the opposite ends and still consist of two sister chromatids
61
explain cytokinesis after telophase 1
usually cytokinesis occurs after telophase 1 and two haploid daughter cells are formed sometimes the chromosomes uncoil and the nuclear envelop reforms
62
is there a interphase after meiosis 1
in some yes in others daughter cells produced divide immediately in either case NO chromosome duplication occurs between telophase 1 and the beginning of meiosis 2
63
explain prophase 2
a spindle fibre forms and moves the chromosomes toward the middle
64
explain metaphase 2
the chromosomes align at the middle and begin to be pulled to the opposite sides
65
explain anaphase 2
the centromeres of sister chromatids finally separate and the sister chromatids of each pair are now individual daughter chromosomes and move to opposite sides of the poles
66
explain telophase 2
nuclei form at the cell poles and cytokinesis begins as well
67
after meiosis 2 what are the results
four daughter cells each with the haploid number of (single) chromosomes
68
is meiosis 2 the same as mitosis
basically yes
69
a cell has the haploid number of chromosomes but each chromosome has two chromatids. the chromosomes are arranged singly at the center of the spindle. what is the meiotic stage
metaphase 2
70
what do we start with in meiosis
one cell with one nucleus | two copies of each homologous pair of chromosome (tetrad)
71
what do we end with in meiosis
four cells | each with one copy of one of the homologous chromosomes
72
where are the chromosomes during meiosis
the nucleus
73
where are the centrosomes during meiosis
the cytoplasm
74
compare mitosis and meiosis - DNA replication
for both mitosis and meiosis the chromosomes duplicate only once during S phase
75
compare mitosis and meiosis - number of cell divisions
mitosis- one division of the nucleus | meiosis - two nuclear and cytoplasmic divisions
76
compare mitosis and meiosis - products
Mitosis - produces two identical diploid cells | meiosis - produces four haploid cells
77
define crossing over
an exchange of corresponding segments between non-sister chromatids of homologous chromosomes
78
what is a chiasma
the place where two homologous chromatids are attached to each other
79
define genetic recombination
the production of gene combinations different from those carried by the original parental chromosome
80
what is a karyotype
a photographic inventory of an individuals chromosomes | an ordered display of magnified images of an individuals chromosomes arranged in pairs
81
what is trisomy 21
an extra copy of chromosome 21 that causes down syndrome
82
what is nondisjunction
an occasional mishap in which the members of a chromosome pair fail to separate
83
explain how nondisjunction could result in a diploid gamete
a diploid gamete would result if the nondisjunction affected all the chromosomes during one of the meiotic divisions
84
Animal life cycle
Start with a diploid(somatic cells)multicellular animal Gamete production - by meiosis - occurs within gonads - produces haploid cells (sperm and egg) Fertilization - forms a diploid zygote
85
Fungus life cycle
Starts with multicellular fungus The haploid structure grows from the spores Gamete production - by mitosis - produces single haploid cells Fertilization - forms a diploid zygote - then divides by meiosis which forms haploid spores
86
Plant life cycle
Starts with multicellular plant that is diploid Produces haploid spores by meiosis Spores germinate creating a haploid multicellular plant Produces haploid gametes by mitosis Fertilization creates a diploid zygote

Biology 1000 (11 decks)

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