Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology - Unit 2 Cells > Cell structure > Flashcards

Cell structure Flashcards

1
Q

What is a eukaryote?

A

An organism of 1 or more cells with DNA in a membrane bound nucleus
- Animals, Plants, Fungi

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

Name the structures in an animal cell

A

Nucleus
Vacuole
Ribosomes
Mitochondria
Cytoplasm
Cell surface membrane
Glycogen Granule
Golgi Body
Golgi Vesicle
Smooth Endoplasmic reticulum
Rough Endoplasmic Reticulum

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

Name the structures in a plant cell

A

Cytoplasm
Cell wall
Cell membrane
Vacuole
Mitochondria
Nucleus
Nucleolus
Chloroplast
RER
Golgi body
Starch grains

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

Storage in Animal cells

A

Glycogen Granule

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

Storage in Plant cells

A

Starch grains

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

What is the structure of ribosomes?

A
  • 2 Sub units
  • Each ribosome made up of ribosomal RNA (rRNA) and proteins
  • Ribosomes are either free in the cytoplasm or attached to the RER
  • 80S ribosomes in eukaryotic cells
  • 70S ribosomes in prokaryotes, mitochondria and chloroplasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the function of ribosomes?

A

Site of protein synthesis

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

Structure of rough endoplasmic reticulum?

A

-Connected to nuclear membrane
-Flattened sacs of membrane (cisternae) filled with fluid
- Studded with ribosomes (‘rough’ with ribosomes)

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

What is the function of the RER?

A

It transports polypeptides (simple proteins) which are made at the ribosomes

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

Structure of the smooth endoplasmic reticulum

A

Same as RER
BUT
no ribosomes in the membrane

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

What is the function of the SER

A

Synthesises and transport lipids

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

What are cisternae?

A

Flattened membrane bound sacs
in SER AND RER
The membranes allow the contents to be kept separate from the cytoplasm of the cell

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

What is the structure of the golgi body?

A
  • Cisternae - flattened membrane sacs filled with fluid
    Usually has vesicles budding off - membrane bound ‘packages’ of molecules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the function of the golgi body?

A

Adds carbohydrates to proteins received from RER to form glycoproteins
- Modifies simple polypeptides into functional proteins and packages them into golgi vesicles for transportation
- Processes and packages lipids
- Makes lysosomes

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

What are the golgi vesicles ?

A

Vesicles move to and fuse with the golgi body
They contain the proteins produced in the RER
They are packaged and processed in the golgi body
They bud off and are delivered to where they’re needed

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

What is the structure of lysosomes?

A

Specialised vesicle (single men range package)
Contains enzymes called lysozymes
Tiny bags of digestive enzyme

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

What is the function of lysosomes?

A

Digest material from phagocytosis
Engulf and digest non-functioning organelle
Release enzymes out of the cells

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

what are hydrolytic enzymes?

A

Enzymes that break biological molecules down

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

What is the structure of the vacuole?

A

In plants - Large, permanent and bound by a single membrane called the tonoplast

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

What is the function of the vacuole?

A

In plants — Storage site for molecules such as water and glucose
Helps keep a pant turgid

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

What are the structures in the nucleus?

A

RER
Ribosomes - on the RER
Nucleoplasm - Like cytoplasm
Nucleolus - Circle
Nuclear envelope - squares around the big circle
Nuclear pore - gaps between the nuclear envelope
Chromatin - unwound dna

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

What is the function of the Nucleus

A

-Contains DNA which codes for the sequence of amino acids in proteins
-DNA undergoes replication in the nucleus
- DNA is the template for mRNA production in protein synthesis

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

What is the function of the nucleolus?

A

Makes rRNA - which is sort of ribosomes

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

What is the structure of the Nuclear envelope ?

A

Double membrane
envelope contains holes called nuclear pores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the function of the nuclear envelope
Allows passage of molecules into/out of nucleus
26
What is the function of the nucleoplasm?
Contains DNA in the form of **protein bound linear DNA** as chromosomes
27
What is the function of chromatin?
Made up of DNA and proteins Provides the instructions for the cell
28
What are histones?
Chromosomes have histones which are **DNA binding proteins** Strands of DNA wrap around histones to form a structure called a nucleosome A chain of nucleosides is called chromatin
29
What is the structure of mitochondria?
Double membrane Folds on the inner membrane called **cristae** which increase the surface area for respiration Contains circular DNA and ribosomes Cylindrical shape increases SA:V ratio for efficient diffusion of oxygen in
30
What is the function of mitochondria
Site of ATP production by aerobic respiration The matrix formed by the cristae contains enzymes needed for aerobic respiration producing ATP
31
What is the structure of chloroplasts?
Double membrane Contains circular DNA and ribosomes Thylakoids - **Flattened membrane sacs containing chlorophyll to absorb light** Granum - **Stacks of thylakoids which increase the SA for the chlorophyll molecules which absorb light for photosynthesis Stroma - **Fluid that the thylakoids are suspended in containing enzymes sugars and starch granules
32
What is the structure of the cell membrane ?
A structure made mainly for phospholipid and proteins On the outside of animals cells and below the cell wall of plant cells
33
What is the function of the cell membrane ?
Regulates the movement of substances into and out of the cell
34
What is the structure of the cell wall
Rigid structure that surrounds cells in plant, algae and fungi Plant cell wall - Made of cellulose microfibrils )which priced strength) embedded in a matrix Algae cell wall - Cellulose/Glycoproteins Fungi cell wall - **chitin** - a nitrogen containing polysaccharide
35
What is the function of the cell wall?
Supports the cell and prevents them from changing shape or lysing
36
Cell organisation
Cell -> Tissue -> Organ -> Organ system -> Organism
37
What is a prokaryote ?
An organism whose DNA is ‘free’ in the cytoplasm Organism with simple structure, containing few organelles - **None of the organelles have a membrane**
38
What are the structure found in prokaryotic cells?
Genetic/Nuclear material Cytoplasm Ribosomes Flagellum Cell wall Capsule Cell surface membrane Plamsid
39
What is genetic/nuclear material
Large circle of DNA
40
What is the cytoplasm
Jelly like containing enzymes and other soluble materials
41
What are the ribosomes
70S Smaller than in eukaryotic cells
42
What is the cell wall in prokaryotic
most have **murein** cell walls made of polypeptide and polysaccharides
43
What is the cell surface membrane
Selectively permeable, substances enter/leave
44
What is the flagellum?
Used for locomotion Allows cell movement
45
What is the capsule ?
layer of slime stops the cell drying out protects the cell
46
What are plasmids?
small circular pieces of dna
47
What are Viruses ?
- ‘Particles’ - **a-cellular (not made of cells) and non living**
48
What is the structure of a virus ?
-Contains generic material (nucleic acid - DNA/RNA) - A capsid - consisting of protein - Attachment proteins - often glycoproteins - attach to specific host cells
49
What is differential centrifugation ?
Used to **separate/isolate different organelles in a cell** Separates different structures of **different density** Cell fractionation is the process used to **separate cellular components while preserving individual functions of each components**
50
Steps of cell fractionation
1) Homogenisation 2) Filtration 3) Ultracentrifugation
51
What is homogenisation?
Cells are first broken **open** in a blender called a homogeniser - This releases the organelles
52
Homogenisation conditions
Ice cold Buffer Isotonic
53
Why ice cold
- Low kinetic energy minimises enzyme reactions - **Prevents autolysis (self digestion) of organelles by hydrolytic enzymes released from lysosomes**
54
Why a buffer?
Maintains the pH which prevents denaturation of proteins
55
Why isotonic
Prevents movement of water in/out of organelles by osmosis This prevents them from bursting or shrivelling
56
Step 2 - Filtration
The homogenised cells are passed through a gauze This separates the debris from the organelles
57
Step 3 Ultracentrifugation
The homogenate (homogenised cells) is poured into a tube placed in a centrifuge The centrifuge spins the tube to separate organelles based on density
58
Ultracentrifugation procedure
- Homogenate is spun in a centrifuge - Most dense organelle form a pellet at the bottom of the tube - Less dense ones remain in the supernatant (liquid) - Spin faster for longer to get the second most dense organelle - Repeat
59
Organelle isolation order
Naughty - Nuclei Clever - Chloroplast (if in plant cell) Monkeys - Mitochondria Like - Lysosomes Eating - Endoplasmic reticulum Raspberries - Ribosomes
60
What are isolated organelles used for ?
To investigate the function of individual cell component eg respiration in mitochondria
61
Which organelles have a double membrane
Nucleus Mitochondria Chloroplasts

Biology - Unit 2 Cells (4 decks)

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