Cells (eukaryotes And Prokaryotes)

Question 1

Functions of nucleus

Answer 1

Control centre of cell through production of mRNA and tRNA- protein synthesis
Retain genetic material of cell as DNA and chromosomes
Manufacture ribosomal RNA and ribosomes

Question 2

Nuclear envelope

Answer 2

Double membrane surrounding nucleus
Outer membrane continuous with endoplasmic reticulum, ribosome on surface
Controls entry and exit of materials
Contains reactions

Question 3

Nuclear pores

Answer 3

Allow passage of large molecules like mRNA out of nucleus

Question 4

Nucleoplasm

Answer 4

Granular jelly like material
Bulk of nucleus

Question 5

Chromosomes

Answer 5

Consist of protein bound linear DNA

Question 6

Nucleolus

Answer 6

Small spherical region within nucleoplasm
Manufactures rRNA
Assembles ribosomes
Can be more than one in a nucleus

Question 7

Mitochondrion

Answer 7

Rod shaped
Site of aerobic stage of respiration, production of ATP

Question 8

Mitochondria double membrane and cristae

Answer 8

Double membrane surrounds mitochondria and controls entry and exit of material
Inner membrane folds to form cristae- extensions
Cristae provide a large surface area for the attachment of enzymes and other protein involved in respiration

Question 9

Mitochondria matrix

Answer 9

Reminder
Contains proteins lipids ribosomes and DNA so mitochondria can control production of own proteins
Many enzymes involved in respiration found here

Question 10

Chloroplasts

Answer 10

Carry out photosynthesis
Disc shaped
Harvest sunlight

Question 11

Chloroplast envelope

Answer 11

Double plasma membrane around it
Highly selective in what it allows to enter and leave the chloroplast

Question 12

Grana, thylakoids, chlorophyll

Answer 12

Grana- stacks of thylakoids, light absorption occurs
Thylakoids- disc like, contains photosynthetic pigment chlorophyll, can join with others in adjacent grana via tubular extensions

Question 13

Stroma

Answer 13

Fluid filled matrix
Synthesis of sugars (next stage of photosynthesis)
Contains starch grains

Question 14

Photosynthetic adaptations: granal membranes

Answer 14

Provide large surface area for attachment of chlorophyll, electron carriers and enzymes that carry out light absorption

Question 15

Photosynthetic adaptations: stroma fluid

Answer 15

Possess all enzymes needed to make sugars in second stage of photosynthesis

Question 16

Photosynthetic adaptations: chloroplasts

Answer 16

Contain both DNA and ribosomes so they can quickly and easily manufacture some proteins for photosynthesis

Question 17

Endoplasmic reticulum

Answer 17

3D system of sheet like membranes spreading through cytoplasm
Continuous with outer nuclear membrane
Membranes enclose a network of tubules and flattened sacs called cisternae

Question 18

Rough endoplasmic reticulum

Answer 18

Ribosomes on outer surfaces of the membrane
Provide a large surface area for the synthesis of proteins and glycoproteins
Provide a pathway for the transport of materials- like proteins throughout the cell

Question 19

Smooth endoplasmic reticulum

Answer 19

Lacks ribosomes
More tubular
Synthesises stores and transports lipids
Synthesises stores and transports carbohydrates

Question 20

Golgi apparatus

Answer 20

More compact SER
Consists of cisternae and vesicles (small rounded hollow structures)
Proteins and lipids produced by ER are passed through Golgi apparatus in sequence
Modifies proteins, adds non protein components to them
Labels proteins for sorting and to be sent to right destination
Modified proteins an lipid transported in Golgi vesicles which can move to the cell surface and fuse with the membrane and release contents to outside

Question 21

Functions of Golgi apparatus

Answer 21

Add carbohydrates to proteins to form glycoproteins
Produces secretory enzymes
Secrete carbohydrates eg for making cell walls
Transport modify and store lipids
Form lysosomes

Question 22

Lysosomes

Answer 22

Formed when vesicles produced by Golgi apparatus contain (digestive)enzymes like proteases and lipases
Contain lysozymes that hydrolyse cell walls of certain bacteria
Releases enzymes to outside or into a phagocytic vesicle within the cell
Hydrolyses old cell organelles for eg

Question 23

Name 2 features of HIV particles that are not found in bacteria

Answer 23

Capsid
RNA transcriptase
Nucleoid
Protein envelope

Question 24

Describe how the scientist will use the information from the colorimeter and her calibration curve to determine the pO2 in a sample of lugworm blood

Answer 24

Measure absorption/ transmission
Plot into calibration curve

Question 25

Membrane bound organelles

Answer 25

Lysosomes
Mitochondria
Chloroplasts
Golgi body
Endoplasmic reticulum
Golgi vesicles

Question 26

Function of capsule

Answer 26

Extra protection against immune system

Question 27

Murein

Answer 27

Glycoproteins
Bacterial cell wall main component

Question 28

Ribosomes

Answer 28

Made from protein and rna

Question 29

Vacuole

Answer 29

Contains sugars and salts (cell sap)
Turgid

Question 30

Specialised cells

Answer 30

A cell with an adaptation specific to its function

Question 31

Tissue

Answer 31

A group of cells working together to perform a specific function
Eg epithelial tissue

Question 32

Organ

Answer 32

A group of tissues working together to perform a specific function
Eg small intestine

Question 33

Organ system

Answer 33

A group of organs working together to perform a specific function
Eg digestive system

Question 34

Describe viral replication

Answer 34

Attachment proteins attach to receptors
Viral nucleic acid enters cell
Nucleic acid replicated in cell OR reverse transcriptase makes DNA from RNA
viral proteins made by cell
Virus assembled and released from cell