unit 1 - cells

Question 1

what is the cell theory?

Answer 1

• all organisms are made up from cells
• all cells come from pre-existing cells or the product of cells
• the cell is the smallest living organisational unit

Question 2

what are some examples of prokaryotic cells

Answer 2

• bacteria and archaea

Question 3

what are some examples of eukaryotic cells

Answer 3

plant, animals, fungi, protists

Question 4

what are some characteristics of eukaryotic cells

Answer 4

• larger, variation in size
• smaller SA: V ratio
• slower diffusion
• membrane bound organelles
• ribosomes attached to the ER and free in the cytoplasm
• DNA located in the nucleus
• DNA in the form of linear, threadlike chromosomes

Question 5

what are some characteristics of prokaryotic cells

Answer 5

• very small
• large SA:V ratio
• diffusion is rapid
• no membrane bound organelles
• ribosomes scattered in the cytoplasm
• DNA is located In a region of cytoplasm
• DNA chromosome in the form of a single strand loop

Question 6

what is cell compartmentalisation

Answer 6

eukaryotes have internal membranes which form membrane bound compartments

Question 7

benefits of cell compartmentalisation?

Answer 7

• it allows enzymes and reactants for a function to be close together in the right conditions
• processes can occur at the same time
• it makes the cell less vulnerable to external changes

Question 8

nucleus structure and function

Answer 8

• membrane bound, contains dna

- contains hereditary information

Question 9

rough endoplasmic reticulum structure and function

Answer 9

• ribosomes bing to its membrane

- processes and modifies proteins

Question 10

ribosomes structure and function

Answer 10

• made of protein and rRNA

- Synthesises Proteins

Question 11

Golgi structure and function

Answer 11

• stack of cistern that are not connected to each other

- processes and packages proteins

Question 12

lysosome structure and function

Answer 12

• vesicle containing digestive enzymes
• only sometimes in plants
• digests cellular waste materials and foreign matter

Question 13

smooth endoplasmic reticulum

Answer 13

• network of cisternae

- synthesises lipids

Question 14

mitochondrion structure and function

Answer 14

• membrane bound. the inner membrane is highly folded and contains DNA
• obtains energy from organic compounds

Question 15

chloroplasts structure and function

Answer 15

• spherical or ellipsoida, contains DNA or thylakoid stacks
• uses light energy, co2 and H2O to produce glucose
• not in animals

Question 16

centriole structure and function

Answer 16

• small structure in the cytoplasm, consisting of microtubules ( only sometimes in plants)
• involved in cell division and the formation of cell structures such as flagella

Question 17

cilliim or flagellum structure and function

Answer 17

• external structure consisting of microtubules

- movement of substance across cell surface

Question 18

vacuole structure and function

Answer 18

• fluid filled vesicle ( large in plants)

- stores substances

Question 19

plastid structure and function

Answer 19

• contains dna

- synthesises and stores various organic molecules

Question 20

cell wall structure and function

Answer 20

• surrounding plasma membrane

- cel structure and protection