2.1 Cell Structure Flashcards Preview

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Flashcards in 2.1 Cell Structure Deck (44)
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1
Q

Define eukaryotic cell

A

Eukaryotic cell - has a nucleus and other membrane bound organelles

2
Q

Define ultrastructure

A

The features that can be seen by using an electron microscope

3
Q

Draw and label a diagram of a plant and Animal cell

A
4
Q

Structure and function of nucleus

A

Nucleus:
• Contains genetic information in form DNA
DNA contains instructions to make proteins
• Controls cells activities -(DNA transcription)

• surrounded by nuclear envelope with nuclear pores
• contain chromatin and nucleus

5
Q

Structure and function of nucleolus

A

•Area in the nucleus
• produces ribosomes
• composed of proteins and RNA

6
Q

Structure and function of nuclear pores

A

• Nuclear envelope contains many pores

• allow substances to move between the nucleus and cytoplasm

7
Q

Structure and function of the smooth endoplasmic reticulum

A

responsible for synthesis and processing lipids and carbohydrates

8
Q

Structure and function of rough endoplasmic reticulum

A

• Surface covered with ribosomes

• responsible for synthesis + transport of proteins
• Folds and processes proteins made at ribosomes

9
Q

Structure and function of Golgi apparatus

A

• Group of fluid-filled membrane- bound flattened sacs. (Cisternae)
• vesicles at edge

•modifies and packages proteins + lipids into vesicles
• makes lysosomes

10
Q

Structure and function of ribosomes

A

• floats free in cytoplasm / attached to RER
• made up of proteins and RNA
• not surrounded by membrane

•site of protein synthesis

11
Q

Structure bad function of mitochondria

A

• oval shaped
• double membrane
•inner membrane folded to form cristae

•site of aerobic respiration producing ATP

•a lot found in active cells requiring lots of energy

12
Q

Structure and function of Lysosomes

A

• a round organelle surrounded by a membrane
• contains hydrolytic enzymes

• Breaks down waste material
↳ digest invading cells or breakdown worn out components of cell

13
Q

Structure and function of chloroplasts

A

•flat structure found in plant cells
•double membrane
•membranes inside called thylakoid membranes
•thylakoid membranes stack forming grana
•grana linked together by lamellae

•site of photosynthesis

14
Q

Structure and function of the plasma membrane/cell surface membrane

A

•inside membrane
• made of lipids and proteins

• regulates movement of substances in and out of the cell
• receptor molecules on it to allow hormone response

15
Q

Structure and function of centrioles

A

• Composed of microtubules
• all animals cells, some plant
• 2 centrioles = centrosome

• separation of chromosomes during cell division

16
Q

Structure and function of cell wall

A

•Rigid - holds shape
• made of cellulose carbohydrate

• A supports cell and plant as a whole
• acts as defense against pathogens

17
Q

Structure and function of cilia

A

• hair like structures on surface membrane of some animal cells.
• Cross section 9+2 - 9 protein microtubules ring and 2 in centre

•Allow cilia to move
More substances along cell surface

18
Q

Structure and function of flagellum

A

•like cilia but longer
• 9+2 arrangement

• microtubules contract flagellum moves
• propel cells forward

19
Q

State differences and similarities between plant and animal cells

A

• both have nucleus, mitochondria, membrane etc
Any plants: chloroplasts, permanent vacuole
, cell wall

20
Q

Outline the process of protein synthesis (step by step)

A

• proteins made at ribosomes
• DNA codes for proteins via mRNA

• RNA leaves nucleus through nuclear pores
• ribosomes on RER synthesise mRNA into proteins
• pass into cisternae and packaged into vesicles
• vesicles move to golgi apparatus using cytoskeleton
• proteins might undergo further processing
• may enter more vesicles to be transported around cell
•secretory vesicles carry proteins to cell membrane
•vesicles fuse with cell surface membrane releasing contents by exocytosis

21
Q

What are the 3 components of the cytoskeleton?

A

• Microfilaments
• microtubules
• intermediate fibres

22
Q

What is the structure of microfilaments?

A

Solid strands
Contractile fibres formed from protein actin

23
Q

What is the function of microfilaments?

A

• Responsible for cell movement + contraction during cytokinesis
• Support + keep (in place) cells organelles

24
Q

What is the structure of microtubules?

A

• Globular tubulin proteins polymerise to form tubes to form scaffold structure

25
Q

What is the function of microtubules?

A

• Determine shape of cell + track movement of organelles
e.g. vesicles

26
Q

What is the function of intermediate fibres?

A

Mechanical strength + help maintain integrity

27
Q

What are the functions of the cytoskeleton in the cell?

A

Support
Strength
Shape
Movement

28
Q

Describe the importance of the cytoskeleton in moving cilia/flagella

A

Pairs of parallel microtubules slide over one another in a beating motion

29
Q

What is the arrangement of microtubules in cilia/flagella?

A

9 + 2 arrangement
2 central microtubules
9 pairs around

30
Q

How is the cytoskeleton dynamic?

A

Constantly changing to respond to changes in the cell and carry out its function

31
Q

What is the importance of the cytoskeleton for neutrophils?

A

•Cytoskeleton shapes and gives neutrophils behaviour
•neutrophils have multilobed nucleus and are very flexible
↳ can squeeze through small spaces to get to infection sites

32
Q

Define prokaryotic cell

A

Cells with no membrane bound nucleus or organelles

33
Q

Give examples of eukaryotic cells

A

Plant
Animal - human liver cell
Fungi

34
Q

Give examples of prokaryotic cells

A

Bacteria - e coli

35
Q

What is the structure and function of the cell wall in prokaryotic cells?

A

• Made of peptidoglycan/murein

•Maintains structure

36
Q

What is the structure and function of ribosomes in prokaryotic cells?

A

• Small - 70s

• Protein synthesis

37
Q

What is the structure and function of bacterial flagellum in prokaryotic cells

A

• Thinner, without 9+2

• rotates with whip like movement to propel cell along

38
Q

What is the structure and function of the plasma membrane in prokaryotic cells?

A

• Controls entry/ exit of the cell

39
Q

What is the structure and function of plasmid in prokaryotic cells?

A

• Rings of DNA in cytoplasma

40
Q

What is the structure and function of Bacterial chromosomes in prokaryotic cells?

A

• Supercoiled - make it compact

• genes grouped into operons - turned on/ off together

41
Q

What is the structure and function of Pili in prokaryotic cells?

A

• Adhesion organelles

-allow bacteria to colonise environmental surfaces /cells
+ resist flushing

42
Q

What is the structure and function of Slime capsule in prokaryotic cells?

A

• Defense + moisture

43
Q

Compare eukaryotic and prokaryotic cells : nucleus, DNA, organelles, cell wall, ribosomes, cytoskeleton, reproduction, cell type, cell surface membrane

A

Nucleus:
P- no E- present
DNA:
P- circular E- linear
Organelles:
P- non-membrane bound E- both with/out membranes
Cell wall:
P- murein E- cellulose (plant only)
Ribosomes:
P- 70s E- 80s
Cytoskeleton:
P- yes E- more complex
Reproduction:
P- binary fission E- asexual/sexual
Cell type:
P- unicellular E- multicellular
Cell surface membrane:
P- yes E- yes

44
Q

What does the endosymbiotic theory state?

A

•Mitochonaria + chloroplasts were once bacteria cells
• theory - these prokaryotes were taken inside another cell as endosymbiont
↳ an organism that lives within the body/cells of another organism