Topic 2A

Question 1

Eukaryotic cells are ..

Answer 1

Are complex and include All animal and plant cells as well as fungi and algae

Question 2

Prokaryotic cells are…

Answer 2

Single called organisms

Question 3

What extra organelle do plant cells have

Answer 3

Cellulose cell wall with plasmodesmata
Vacuole
Chloroplasts

Question 4

Difference between fungal and plant cell

Answer 4

Fungal cell walls made of chitin not cellulose

Fungal calls don’t have chloroplasts

Question 5

Cell surface membrane function

Answer 5

Regulates movement of substance in and out of cell. Has receptor molecules to respond to chemicals like hormones

Question 6

Nucleus function

Answer 6

Controls cell activity
Pores allow substances to move between nucleus and cytoplasm
Nucleulous makes ribosomes

Question 7

Mitochondrion function

Answer 7

Site of aerobic respiration where atp produced

Question 8

Chloroplasts function

Answer 8

Site of photosynthesis some happens in grana and other in stroma

Question 9

Lamellae

Answer 9

Thin flat pieces of thylakoid membrane

Question 10

Stroma

Answer 10

Thick fluid found in chloroplasts

Question 11

Golgi apparatus function

Answer 11

Processes and packages new lipids and proteins and makes lysosomes

Question 12

Golgi Vesicles function

Answer 12

Stores lipids and proteins made by Golgi and transports out the cell via cell surface membrane

Question 13

Lysosomes function

Answer 13

Contains digestive enzymes called lysozymes. Kept separate from cytoplasm by surrounding membrane and can be used to digest invading cells or break down worn out components of cell

Question 14

Ribosome function

Answer 14

Site where proteins are made

Question 15

Rough endoplasmic reticulum function

Answer 15

Folds and processes proteins that have been made at the ribosomes

Question 16

Smooth endoplasmic reticulum

Answer 16

Synthesises and processes lipids

Question 17

Cell wall function

Answer 17

Supports cell and prevents it changing shape

Question 18

Cell vacuole function

Answer 18

Helps to maintain pressure inside the cell and keep it rigid
Stops wilting
Involved in isolation of unwanted chemicals inside the cell

Question 19

Capsule

Answer 19

Made of secreted slime, helps protect bacteria from attack cells from immune system

Question 20

Plasmids

Answer 20

Small loops of DNA that contain genes for things like antibiotic resistance

Question 21

Flagellum

Answer 21

A long hair like structure that rotated to make the prokaryotic cell move

Question 22

4key points about viruses

Answer 22

Just nucleic acids surrounded by protein, not alive
Smaller than bacteria
Have no plasma membrane, no cytoplasm and no ribosomes
Reproduce inside host cells

Question 23

Virus structure

Answer 23

Contain a core of genetic material either DNA or RNA
Protein coat around core is capsid
Attachment proteins stick out from edge of capsid so can cling on host cell

Question 24

Binary fission

Answer 24

Circular DNA and plasmids replicate
Cell gets bigger and DNA loops move to opposite poles of cell
Cytoplasm begins to divide and cell walls begin to form
Cytoplasm divides and two daughter cells produced with one copy of circular DNA each

Question 25

Light microscopes

Answer 25

Source : Light radiation Magnification: upto 1500x Resolution : 0.2 micrometers Resulting image: black and white 2D

Question 26

Sample preparation for light microscope

Answer 26

Sample is washed, add a simple chemical and put a cover slip over it

Question 27

Scanning electron microscopes

Answer 27

Source: Scan beam of electron across specimen knocking off electrons from specimen and gathering in cathode tube to form image Resolution: 20nm, lower than TEM Magnification: x1,500,000 Resulting image: 3D image

Question 28

SEM sample preparation

Answer 28

Coat specimen with thin layer of gold | Must be in a vacuum

Question 29

Transmitting electron microscope

Answer 29

Source: Electromagnets focus beams of electrons which is then transmitted through specimen Resolution: 0.1 nm, high Resulting image: 2D Black white

Question 30

TEM sample preparation

Answer 30

Must be in a vacuum | Slice and stain

Question 31

Homogenisation

Answer 31

Done by vibrating cells or grinding in blender. Breaks up the plasma membrane and releases organelle into solution Solutions must be ice cold to reduce enzyme activity that break down organelle Must be isotonic, and use buffer solution

Question 32

Filtration

Answer 32

Homogenised cell solution filtered through gauze to separate large debris or tissue

Question 33

Ultracentrifugation

Answer 33

Cell fragments poured into tube which is put in centrifuge and spun at low speed. Heaviest organelle like nuclei form pelt Supernatant drained off and spun at higher speed, repeated with higher speeds until all organelles are separated

Question 34

Interphase

Answer 34

Cell prepares to divide | DNA unravels and replicated to double genetic content

Question 35

Prophase

Answer 35

Chromosomes condense getting shorter and fatter Bundles of proteins called centrioles move to opposite ends of the cell forming network of protein fibres called spindles Nuclear envelope breaks down and chromosomes lie free in cytoplasm

Question 36

Metaphase

Answer 36

Chromosomes line up along the equator and become attached to spindle by there centromere

Question 37

Anaphase

Answer 37

Centromeres divide departing each pair of sister chromatids. Spindles contract pulling chromatids to opposite poles of the spindle, centromere first

Question 38

Telaphase

Answer 38

Chromatids reach opposite poles on the spindle. Uncoil and become long and thing again (chromosomes) Nuclear envelope forms around each group of chromosomes

Question 39

Cytokinesis

Answer 39

Cytoplasm divides and there are now two daughter cells that are genetically identical to original

Question 40

Cancer treatment: G1 (cell growth and protein production)

Answer 40

Some chemical drugs prevent synthesis of enzymes needed for DNA replication. If these aren’t produced cell unable to enter synthesis phase forcing to kill itself

Question 41

Cancer treatment: S Phase (DNA replication)

Answer 41

Radiation and some drugs damage DNA, if damaged DNA detected, it will kill itself Not enough DNA for two daughter nuclei

Question 42

Ribosomes found in prokaryotic cells

Answer 42

70S