Eukaryotic cells

Question 1

Cell theory

Answer 1

All living things are made from one or more cells

Cells are the basic units of all life

Cells arise from pre-existing cells

Question 2

Key features of eukaryotic cells

Answer 2

• animals, plants, fungi, protista
• large
• distinct nucleus surrounded by a nuclear membrane
• membrane bound organelles

Question 3

Levels of organisation

Answer 3

Specialised cells > tissues > organs > organ systems > organism

Question 4

Eukaryotic plant cells

Answer 4

Cell membrane, 
cell wall, 
lysosomes, 
golgi, 
SER, 
nucleus, 
nucleolus, 
RER, 
ribosomes, 
vacuole, 
mitochondria, chloroplasts

Question 5

Mitochondria cell

Answer 5

Inner + outer membrane, inter membrane space, matrix, cristae

Question 6

Chloroplast structure

Answer 6

Innter + outer membrane, stroma, thylakoid, grana, lamella

Question 7

Cell membrane

Answer 7

• phospholipid bilayer with embedded proteins
• selectively permeable - enables control of passage of substances in and out the cell
• barrier between internal and external environment of cell

Question 8

Nucleus + nucleolus

Answer 8

• nuclear envelope, nuclear pores, nucleolus, DNA / chromatin
• controls the cells activity through transcription of mRNA
• nuclear pores allow substances to move between the nucleus and cytoplasm
• nucleolus makes ribosomes which are made up of proteins and ribosomal RNA

Question 9

Mitochondria

Answer 9

Double membrane - inner membrane folded to form cristae, matrix containing small 70S ribosomes, small circular DNA and enzymes involved in aerobic respiration (glycolysis)

Site of aerobic respiration in which ATP is produced

Question 10

Chloroplasts

Answer 10

Thylakoid membranes are stacked up in some parts to form grana, which are linked by lamellae. These sit in the stroma and are surrounded by a double membrane, contain starch granules and circular DNA

Chlorophyll absorbs light for photosynthesis to produce organic substances

Question 11

Golgi

Answer 11

3 or more fluid filled membrane bound sacs with vesicles at edge

Receives protein from RER

Processes proteins

Packages into vesicles

Makes lysosomes

Question 12

Lysosome

Answer 12

Type of golgi vesicle containing lysozymes- hydrolytic enzymes

Release of lysozymes to hydrolyse pathogens or worn out cell components

Question 13

Ribosome (80S)

Answer 13

Float free in cytoplasm or bound to rER, not membrane bound

Made from 1 large and 1 small subunit

Site of protein synthesis, translation

Question 14

RER (rough endoplasmic reticulum)

Answer 14

Ribosomes bound by a system of membranes

Folds polypeptides to secondary structure

Packages to vesicles transport to the Golgi apparatus etc

Question 15

sER (smooth endoplasmic reticulum)

Answer 15

System of membranes

No ribosomes

Synthesises and processes lipids

Question 16

Cell wall

Answer 16

Made mainly of cellulose in plants song algae’s, and of chitin in fungi

Rigid structure surrounding cells in plants, algae and fungi. Prevents the cell changing shape and bursting (lysis)

Question 17

Vacuole

Answer 17

Contains cell sap - weak solution of sugars and salt.

Tonoplast - surrounds double membrane

Maintains pressure in the cell (stops wilting)

Stores/isolates unwanted chemicals in the cell

Question 18

Protein transport

Answer 18

1. Proteins leave RER in a transport vesicle
2. Vesicle fuses with the golgi
3. Protein moves through the golgi and becomes modified
4. Modified proteins exit golgi in a new vesicle
5. Vesicles can be secreted from the cell or stay in the cell as a lysosome