Cells Flashcards

1
Q

Three original tenets of cell theory

A
  1. All living things consist of cells
  2. The cell is the smallest and basic unit of life
  3. All cells originate from pre-existing cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Tenets of modern Cell Theory

A
  1. All living things consist of cells
  2. The cell is the smallest and basic unit of life
  3. All cells originate from pre-existing cells

Modern additions:

  1. The activity of an organism depends on the total activity of independent cells.
  2. Energy flow (metabolism and biochemistry) occurs within cells.
  3. Cells contain DNA, the hereditary information.
  4. All cells are basically the same in chemical composition in organisms of similar species.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Function of chromatin network

A
  • Made of DNA and proteins
  • Contains genes (hereditary information)
  • Instructs all the activities of the cell
  • Packaged as chromosomes for cell division
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

All eukaryotic cells have…

A
  • Cell membrane
  • Cytoplasm
  • Organelles
  • Nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Only plant cells have…

A
  • Cell wall (though fungi also have a cell wall)
  • Large central vacuole
  • Plastids e.g. chloroplasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Structures making up the cell wall of plants

A
  • Primary cellulose wall
  • Secondary lignin wall
  • Middle pectin lamella
  • Pits
  • Plasmodesmata
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Primary cellulose wall function

A

shape

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

Secondary lignin wall function

A

strength

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

Middle pectin lamella function

A

joins cells together

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

Pits in cell wall function

A

ease transport between cells

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

Plasmodesmata function

A

joint cell cytoplasms for communication and transport between plant cells

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

Useful substances made from plant cell walls

A
  • Wood
  • Paper
  • Cork
  • Cotton
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Structures of cell membranes

A
  • Phospholipid bi-layer
  • Carrier and channel proteins
  • Carbohydrates
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Function of carrier and channel proteins in a cell membrane

A

control movement of larger substances into and out of a cell

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

Function of the carbohydrates on the surface of a cell membrane

A

cell recognition

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

Parts of the phospholipid bi-layer

A
  • Hydrophilic head
  • Hydrophobic tail
  • Hydrophobic tail
  • Hydrophilic head
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Types of movement across a membrane

A

Diffusion

Osmosis

Facilitated transport

Active transport

18
Q

Two types of osmosis

A

Endosmosis (water movement into cell)

Exosmosis (water movement out of cell)

19
Q

Process of diffusion

A
  • Passive process (no energy required)
  • Non-selective movement along concentration gradient
  • From high to low concentrations until equilibrium
  • E.g. oxygen
20
Q

Process of osmosis

A
  • Selectively permeable membrane
  • Passive process (no energy required)
  • Movement of water into or out of cell
  • Water moves along concentration gradient
  • From high water potential to low water potential until equilibrium
21
Q

Process of facilitated transport

A
  • Living selectively permeable membrane
  • Carrier proteins required
  • passive process (no energy required)
  • selective movement of substances along concentration gradient using carrier proteins until equilibrium
  • e.g. Glucose
22
Q

Process of active transport

A
  • living selectively permeable membrane
  • carrier proteins required
  • active process ATP required
  • selective movement of substances
  • against a concentration gradient (from low to high)
  • e.g. sodium and potassium ions
23
Q

Endocytosis

A
  • In animal cells
  • Process of taking in food particles and nutrients
  • Also called phagocytosis
  • structure formed called a food vacuole (membrane bound)
24
Q

Exocytosis

A
  • In animal cells
  • structure involved called secretory vesicle (membrane bound)
  • Process or removing particles and metabolic wastes
  • Also called elimination or secretion
25
Q

Other cell membrane structures in animal cells

A

Microvilli - increase surface area

Pinocytic vesicles - take up liquids

Phagocytic vesicles - take up particles using pseudopodia

26
Q

Structures of the nucleus

A

Double membrane

Nucleopores

Nucleoplasm

Chromatin network

Nucleolus

27
Q

Two types of endoplasmic reticulum (ER)

A

Smooth ER - no ribosomes attached

Rough ER - ribosomes attached

28
Q

Function of the endoplasmic reticulum

A

Connects cell membrane with nucleus

A network of membrane bound tubes

For transporting substances

Rough ER makes and transports proteins

29
Q

Cytoplasm contents

A
  • Water (90%)
  • Enzymes
  • Protein cytoskeleton
  • Organelles
30
Q

Function of ribosomes

A

Protein synthesis

31
Q

Examples of vacuoles

A

Contractile vacuole - controls water content of cell

Lysosome - contains peroxidase enzyme

Phagocytic vesicle - contain food particles

Pinocytic vesicle - take up fluids

32
Q

Tonoplast

A

Membrane that surrounds a vacuole

It can provide turgidity (support) to the cells

33
Q

Structure of a mitochondrion

A
  • Double membrane
  • Cristae - internal folds
  • Matrix - internal fluid
34
Q

Function of the mitochondrion

A
  • Where cellular respiration takes place
  • Production of ATP (energy carrier molecules)
  • Provides energy for the cell
35
Q

Golgi body (animal cells) and dictyosomes (plants) structure and function

A

Stacked flapjack like membrane bound structure

Packaging centre of cell

Sort and store cellular secretions e.g. enzymes

36
Q

Types of plastids (plant cells)

A
  • Leucoplasts - no pigments (storage organelle)
  • Chromoplasts - yellow-red pigments
  • Chloroplasts - green pigments
37
Q

Structure of a chloroplast

A
  • Double membrane
  • Stroma - inner fluid
  • Thylakoids - membrane structures with chlorophyl
  • Grana - stacked thylakoids
  • Inter-granum lamella - membrane bridges between grana
  • Occasionally: starch granules
38
Q

Chlorophyll

A
  • Green pigment
  • Captures light energy
  • Needed for photosynthesis
39
Q

Structure and function of the centrosome

A
  • Made of two centrioles
  • act as anchors during cell division
  • and form the spindle apparatus
40
Q

Cell differentiation

A
  • A process where cells change size, shape and composition
  • to be able to perform specific function
  • also called cell specialisation
41
Q

Undifferentiated cells in plants and animals

A
  • Stem cells - animals
  • Meristem cells - plants