Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > Cells > Flashcards

Cells Flashcards

(81 cards)

Start Studying
1
Q

What do cells make up ?

A

Tissues - Organs - Organ systems - Organism

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

What are the necessary features of living organisms?

A

Movement - change position
Respiration - release energy from food
Sensitivity - respond to things
Growth - gets bigger
Reproduction - makes copies of itself
Excretion - remove waste material
Nutrition - consumes chemical material

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

What does the cell membrane do ?

A

Controls what passes in and out of a cell

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

What does the cell wall do ( plants ) ?

A

Gives the cell strength - made up of cellulose which is strong

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

What does the vacuole do ( plants ) ?

A

Contains sap, helps support shape of cell

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

What do chloroplasts do ( plants ) ?

A

Contain chlorophyll, needed for photosynthesis

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

What do ribosomes do ?

A

Make protein - protein synthesis

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

What does the nucleus do ?

A

Controls activities of the cell
Contains DNA

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

What does cytoplasm do ?

A

Where most of the chemical reactions take place

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

What does mitochondria do ?

A

Where aerobic respiration takes place

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

What is a eukaryotic cell ?

A

Plant cell, fungi cell or animal cell

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

What is a prokaryotic cell ?

A

Bacteria or archaea cell

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

Size of eukaryotic cell

A

5 - 100 micrometres

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

Size of prokaryotic cell

A

0.2 - 2 micrometres

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

Where is the genetic material of a eukaryote found ?

A

In a nucleus

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

Where is the genetic material of a prokaryote found ?

A

A single molecule, found free in the cytoplasm - circular DNA
May have extra rings of DNA called plasmids.

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

What do eukaryotic cells contain that prokaryotic cells do not ?

A

Membrane-bound organelles

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

How do eukaryotic cells divide ?

A

Mitosis

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

How do prokaryotic cells divide ?

A

Binary fission

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

What is magnification ?

A

The ability of a lens or other optical instrument to enlarge the size of something.

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

Equation for magnification

A

Total magnification = magnification of eye piece x magnification of objective lens

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

What is an electron microscope ?

A

A microscope that uses a beam of electrons as a source of illumination. They use electron optics that are analogous to the glass lenses of an optical light microscope to control the electron beam.

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

Transmission electron microscopes

A

Used to look at extremely thin sections of cells. Highest magnification obtained from a TEM is 1,000,000x.

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

Scanning electron microscopes

A

Work by bouncing electrons off the specimen that had an ultra-thin coating of heavy metal applied.
Used to reveal the surface shape of structures such as small organisms and cells.
Resolution and magnification is lower than in TEMs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Pros of electron microscopes
High magnification High resolution Ability to see inside cells
26
Cons of electron microscopes
Expensive Cells have to be dead Not portable Need training to use No colour Slides have to be made in a vacuum
27
Resolution definition
The ability of a microscope to distinguish 2 points as separate from one another.
28
Pros of light microscopes
See colour Affordable Easy to use Portable Specimen can be living
29
Cons of light microscopes
Low magnification Low resolution
30
Micrometre in metres
0.000001 metres ( -6 )
31
Nanometre in metres
0.000000001 metres ( -9 )
32
What is a specialised cell ?
When cells or tissues become adapted to carry out their specific function
33
What is differentiation ?
When cells gain certain features needed for their functions ( when they have become specialised )
34
Muscle cell function
Contraction for movement
35
Ciliated epithelial cell function
Line the airways and protect from pathogens
36
Root hair cell function
Absorption of water and minerals from soil
37
Egg cell function
A gamete used in sexual reproduction
38
Fat cell function
Acts as an energy store
39
Phloem cell function
Transport of dissolved sugars and amino acids
40
Xylem cell function
Transport tissue for water and mineral ions
41
Palisade cell function
Carry out photosynthesis in the leaves
42
Red blood cell function
To transport oxygen around the body
43
Nerve cell function
To carry electrical impulses around the body
44
Sperm cell function
A gamete used in sexual reproduction
45
Guard cell function
Open and close the stomata to allow gas exchange in plants
46
Cone cell function
To allow colour vision
47
Adaptations of muscle cells
Contain filaments that contract Lots of mitochondria to provide sufficient energy for muscle contraction
48
Adaptations of ciliated epithelial cells
Mucus is made by goblet cells, mucus trap pathogens Contains cilia which waft mucus
49
Adaptations of root hair cells
Has a projection to increase surface area Thin walls for short diffusion distance No chloroplasts
50
Adaptations of egg cell
Contains a nucleus with half the number of chromosomes Cell membrane changes after fertilisation so sperm cannot enter
51
Adaptation of fat cells
Contains a fat store which can be broken down to release energy Can increase in size to store more fat
52
Adaptation of phloem cells
Joined end to end to make a tube Few organelles to aid the flow of materials
53
Adaptation of xylem cells
Line up in tubes and the individual cell walls break down to make xylem vessels Contains lignin, which strengthens the vessel
54
Adaptations of palisade cells
Contain many chloroplasts Chloroplasts are found near the top of the cell, where the most light is found
55
Adaptations of red blood cells
No nucleus to create more space for oxygen Large surface area
56
Adaptations of nerve cells
Long and thin to carry for long distances Lots of mitochondria to release large amount of energy
57
Adaptation of sperm cells
Nucleus has half the number of chromosomes Acrosome in the head contains enzymes to break down outer layer of egg cell
58
Adaptation of guard cells
Found in pairs Change shape to open and close the stomata
59
Adaptation of cone cells
Contains visual pigment One end usually links up to a nerve cell so our body can respond to visual stimuli
60
What are stem cells ?
Undifferentiated cells which are capable of self-renewal to produce more stem cells ( via mitosis ) or differentiate into specific specialised cells.
61
Where are embryonic stem cells found ?
In 3-5 day old embryos
62
Where are adult stem cells found ?
Rare and only found at specific locations eg bone marrow
63
Where are umbilical cord stem cells found ?
In the umbilical cord, which has a rich source of stem cells formed from the placenta
64
What can embryonic stem cells differentiate into ?
Any type of cell
65
What can adult stem cells differentiate into ?
Cells from the type of tissue they were found in
66
What can umbilical cord stem cells differentiate into ?
Blood cells - used to treat blood disorders
67
Therapeutic cloning
An embryo is produced with the same genes as the patient. Stem cells from the embryo are collected and used to treat the patient, as they won't be rejected
68
What is the meristem ?
A layer of unspecialised stem cells in a plants roots and shoots. They have the ability to become any type of plant cell.
69
Why are plant stem cells useful ?
Clones can be made quickly and efficiently - rare plants can be grown to avoid extinction Produced to sell - economic benefit Crops with ideal features like disease resistance can be clones For research Food Medicinal properties
70
What is mitosis ?
Cell division that results in genetically identical diploid cells
71
What is mitosis used for ?
Growth and development of tissues in multicellular organisms Repair of tissues in multicellular organisms Asexual reproduction in multicellular organisms + binary fission in unicellular organisms
72
1. Interphase - G1
Sub cellular structures duplicate eg ribosomes and mitochondria
73
2. Interphase - S
DNA replicates to form 2 copies of each chromosome, each chromosome consisting of 2 sister chromatids, connected in the centre by a centromere.
74
3. Interphase - G2
DNA is checked for errors made during replication. Done using enzymes, and any error can be fixed.
75
4. Mitosis
The chromosomes move to opposite poles of the cell and two nuclei form
76
5. Cytokinesis
Cytoplasm divides and cell membrane separates, creating 2 new genetically identical daughter cells
77
6. G0
Temporary cell resting. Some cells eg nerve cells will never divide again
78
Mitosis 1.Prophase
DNA condenses Nuclear membrane disappears Spindle fibres form from centrioles
79
Mitosis 2.Metaphase
Chromosomes line up at the equator Spindle fibres attach to chromosomes
80
Mitosis 3.Anaphase
Chromatids are pulled apart, by spindle fibres and motor proteins, towards poles
81
Mitosis 4.Telophase
Nuclei form around the chromosomes Spindle fibres disintegrate

Biology (8 decks)

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