B1- Cell structure and transport

Question 1

Magnification

Answer 1

How large an object will appear compared to it’s actual size

Question 2

Resolution

Answer 2

The smallest distance that two objects can be seen as apart

Question 3

Image size equation

Answer 3

Image size= actual size x magnification

Question 4

Light microscope
Developed?
Uses what?
Magnification?
Expense?
Resolving power?

Answer 4

-Developed first
-Uses a beam of light
-X2000
-Cheaper
-Lower

Question 5

Electron microscope
Developed?
Uses what?
Magnification?
Expense?
Resolving power?

Answer 5

-Developed later
-Uses beam of electrons
-X2,000,000
-Expensive, hard to care for
-Higher

Question 6

How to use a microscope

Answer 6

Drop of water on slide, flat slice of onion, drops of iodine, dab excess with paper towel. Lower coverslip with mounted needle. Place on stage and use arms to hold. Lowest objective lens first. Coarse focus then fine focus.

Question 7

Sub cellular structures in animals and plant cells

Answer 7

Animal- nucleus, cell membrane, cytoplasm, mitochondria, ribosome
Plant- nucleus, cell membrane, cytoplasm, mitochondria, ribosome, cell wall, vacuole, chloroplast

Question 8

Def..
Nucleus?
Cytoplasm?
Cell membrane?
Mitochondria?

Answer 8

Controls the activities of the cell and contain genetic info
Substance where chemical reactions take place
Controls movement of substances in & out of cell
Aerobic takes place, releases energy

Question 9

Def..
Ribosome?
Cell wall?
Vacuole?
Chloroplast?

Answer 9

Where protein synthesis takes place
Strengthens cell with cellulose
Filled w cell sap to keep cell rigid
Contain chlorophyll which absorbs sunlight for photosynthesis

Question 10

What do chloroplasts, ribosomes and mitochondria look like in a diagram?

Answer 10

Green ovals
Joined/close together dots/ovals
Ovals may have zigzags

Question 11

Examples of eukaryotes and prokaryotes cells?

Answer 11

Prokaryotes- bacteria
Eukaryotes- animal, plant, fungi

Question 12

Prokaryotes 8 features

Answer 12

Has cell membrane and cytoplasm, no nucleus, circular DNA loop, could have plasmids (extra rings of DNA) or flagella, smaller, uni-cellular

Question 13

Eukaryotes 6 features

Answer 13

Has nucleus, cell membrane and cytoplasm, DNA in nucleus, larger, uni or multi cellular

Question 14

Similar features of eukaryotes and prokaryotes

Answer 14

Contain DNA, ribosomes, cytoplasm, cell membrane

Question 15

How to calculate orders of magnitude

Answer 15

If bigger number divided by smaller number is close to 10=1 order, close to 100=2 orders

Question 16

Specialised cell definition

Answer 16

Cell that has an adapted structure to perform a specific function

Question 17

Red blood cell
Adaptations and Functions

Answer 17

No nucleus, biconcave, contains haemoglobin
Collect oxygen from lungs and carry around body

Question 18

Egg cell
Adaptations and Functions

Answer 18

Has nucleus, round shape, mitochondria
To be fertilised and develop into foetus

Question 19

Sperm cell
Adaptations and Functions

Answer 19

Streamline shape, flagellum, mitochondria, nucleus
To swim and fertilise egg

Question 20

Nerve cell
Adaptations and Functions

Answer 20

Long thin axon, millions of nerve endings, mitochondria
Send and receive electrical messages

Question 21

Root hair cell
Adaptations and Functions

Answer 21

Large epidermal extension increase sa, lots of mitochondria for active transport
Absorb water, take in minerals

Question 22

Xylem
Adaptations and Functions

Answer 22

Thickened walls, hollow tube, dead cells, lignin walls
Carry water, dissolved minerals from roots to leaves

Question 23

Phloem
Adaptations and Functions

Answer 23

Living cells, sieve plates, no end walls
Carry dissolved sugars and amino acids around

Question 24

Striated muscle cell
Adaptations and Functions

Answer 24

Long thin shape when relaxed but short fat when tight, store glycogen, can be broken down for energy
Control movements in the body, contract & relax

Question 25

Diffusion definition How long does it occur?

Answer 25

Movement of particles from an area of high conc to area of low conc Move until equilibrium

Question 26

Net movement equation?

Answer 26

Particles moving in- particles moving out

Question 27

4 Factors that affect the rate of diffusion

Answer 27

Temperature, distance, surface area, conc gradient

Question 28

SA:Volume ratio in different sized animals

Answer 28

Large animal-small ratio Small animal-large ratio

Question 29

Examples of diffusion 2 human, 1 plant

Answer 29

Food molecules-Small intestine to blood Oxygen-Alveoli to blood Water-Soil to plant roots

Question 30

Osmosis definition

Answer 30

Diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane

Question 31

Water and solute in... Dilute solution? Concentrated solution?

Answer 31

High conc of water, low conc of solute Low conc of water, high conc of solute

Question 32

Partially permeable membrane

Answer 32

A membrane with small holes to only let through water

Question 33

What happens when an animal cell is placed in a hypertonic solution?

Answer 33

-High conc of water, low conc of solute inside cell -Water moves out of cell -Cell shrivells

Question 34

What happens when an animal cell is placed in a isotonic solution?

Answer 34

-Same conc of water and solute inside cell -No movement of water -Cell unchanged

Question 35

What happens when an animal cell is placed in a hypotonic solution?

Answer 35

-High conc of water, low conc of solute outside cell -Water moves into cell -Cell swells and bursts

Question 36

Plasmolysis

Answer 36

The loss of water from a plant cell by osmosis

Question 37

Turgor

Answer 37

The pressure against the cell wall, when a cell contains lots of water

Question 38

What state will a plant cell be in a hypertonic, isotonic and hypotonic solution?

Answer 38

Hypertonic-plasmolysed Isotonic- flaccid Hypotonic-turgid (normal)

Question 39

How to investigate osmosis in plant cells?

Answer 39

-Measure 30cm3 distilled water in boiling tube -Measure and label 30cm3 sucrose solution, conc 0.4, 0.8, 1.2mol/dm in three other tubes -Use a cork borer to create 4 potato cylinders then use a scalpel and ruler to make them 3cm -Weigh each cylinder and record the mass -Put each in a boiling tube, leave for 1 hour -Take potatoes out and roll gently on paper towel -Record their new mass and calculate change -Repeat experiment and calculate mean to improve accuracy

Question 40

Active transport

Answer 40

Movement of substances from a dilute solution to a more concentrated solution using energy

Question 41

Examples of active transport in plants and animals

Answer 41

Plants- Root hair cell, ions in soil to the cell Animals- Human gut, glucose from intestine to blood