Topic 1- Cell Structure and Transport

Question 1

Calculating magnification- If the eyepiece lens is x4 and the objective lens is x10, what is the total magnification of the microscope?

Answer 1

4x10 = 40

Question 2

Finish the sentence about the differences between light and electron microscopes- “Light microscopes have a _________ resolution than electron microscopes are ________ expensive than light microscopes”

Answer 2

Smaller, more.

Question 3

Finish the equation to find magnification - Image size = __________ x size of ______ ________

Answer 3

Magnification, size of real object

Question 4

What does the nucleus do?

Answer 4

Controls all activities of the cell.

Question 5

What does the cytoplasm do?

Answer 5

Allows reactions to take place in its liquid gel and holds the cell together.

Question 6

What does the cell membrane do?

Answer 6

Controls the passage of substances in and out of the cell like glucose or water and is semi-permeable.

Question 7

What do the mitochondria do?

Answer 7

Allows aerobic respiration to take place, providing energy for the cell.

Question 8

What purpose do the ribosomes serve?

Answer 8

This is where protein synthesis takes place, making all protein needed in the cell.

Question 9

Plant and animal cells share many characteristics but plant cells have three extra organelles that separate them from plant cells, which are they?

A: Nucleus, Mitochondria, Chloroplasts
B: Cell Wall, Chloroplasts, Vacuole
C: Vacuole, Cell Membrane, Cytoplasm.

Answer 9

B: Cell Wall, Chloroplasts, Vacuole.

Question 10

Plant and animal cells are examples of what type of cell?

A: Prokaryotic
B: Eukaryotic

Answer 10

B: Eukaryotic.

Question 11

The chemical that stores genetic information is called?

Answer 11

DNA.

Question 12

Finish the sentence with the collect letter answer - Bacteria are _______-celled organisms.

A: Single-celled
B: Multi-celled.

Answer 12

A: Single-celled.

Question 13

Finish the sentence about bacterium - Humans are unable to see bacteria without a __________.

Answer 13

Microscope.

Question 14

The Human eye can only see as small as a eukaryotic cell which is ___ __ in length. What letter finishes the sentence?

A: 100 micrometers
B: 10 micrometers

Answer 14

100 micrometers.

Question 15

A light microscope can see far more than the human eye, being able to see prokaryotic cells at as low as _ micrometer(s). What letter finishes the sentence?

A: 10 micrometers
B: 1 micrometer

Answer 15

B: 1 micrometer

Question 16

Electron microscopes, being far more expensive and using different technology, can observe as small as 1 ____________, 1000 times as powerful as a light microscope!
What letter finishes the sentence?

A: nanometer
B: picometer

Answer 16

A: Nanometer.

Question 17

Nerve cells are specialised to send electrical _______ around the body. What word finishes the sentence?

Answer 17

Impulses.

Question 18

Nerve cells have many adaptations which allow them to communicate messages around the body. They have lots of _________ to connect to other cells. What word finishes the sentence?

Answer 18

Dendrites.

Question 19

Nerve cells have axons, what purpose do they serve?

Answer 19

Axons carry nerve impulses from one place to another.

Question 20

How are synapses adapted to transmit signals from one cell to another?

Answer 20

The synapses use transmitter chemicals to transfer electrical signals and have many mitochondria to provide energy needed to make these chemicals.

Question 21

What is the main purpose of sperm cells?

Answer 21

To fertilise and egg cell to make a foetus.

Question 22

How are sperm cells adapted to fulfil their purpose? Name 4 ways.

Answer 22

1) They have tails which allow them to be aerodynamic and move towards the egg.
2) Their middle section is full of mitochondria which provide energy needed for the tail to move.
3) The acrosome stores digestive enzymes for breaking down the outer layers of the egg to penetrate.
4) Sperm cells contain a large nucleus to contain the information to be passed on during fertilisation.

Question 23

Muscle cells ______ and _____. What two words finish this sentence?

Answer 23

Contract, relax.

Question 24

Striated muscle cells work together in ______. What word finishes this sentence?

Answer 24

Tissues.

Question 25

Why do muscle cells form one of the layers of digestive tissue in the stomach?

Answer 25

So that they can push digested food out by contracting and relaxing.

Question 26

Striated muscle cells contain glycogen, an important chemical in cellular respiration that can be broken down. This is one of their adaptations, name two other adaptations of striated muscle cells.

Answer 26

1) They contain special proteins that slide over each other, making fibres contract. 2) They contain many mitochondria which produce energy which reactions need to take place.

Question 27

What do root hair cells do for plants?

Answer 27

They uptake water and mineral ions used for growth and functions in the plant via active transport.

Question 28

Root hair cells have three main adaptations, which are these?

Answer 28

1) They have a large surface area, allowing them more area for water to enter passively. 2) They have a large permanent vacuole which speeds up the movement of water by osmosis by storing more of it, 3) They contain many mitochondria which are needed for active transport of mineral ions to the cell.

Question 29

What function do chloroplasts carry out?

Answer 29

They allow light energy to be transferred into energy used by the cell by photosynthesis.

Question 30

Where are photosynthetic cells placed?

Answer 30

Throughout the cell in many layers to allow maximum light absorption.

Question 31

What organelle do photosynthetic cells have which keeps them rigid?

Answer 31

A permanent vacuole, via osmosis.

Question 32

Xylem are a group of cells that transport which material?

Answer 32

Water and mineral ions.

Question 33

From what area does the xylem travel materials to?

Answer 33

From the roots to the shoots and highest leaves.

Question 34

What chemical is present in xylem cells, causing them to die and from rigid tubes of dead cells?

Answer 34

Lignin.

Question 35

Phloem transport what materials throughout the cell?

Answer 35

Food made by photosynthesis in the leaves, which provides energy for all areas of the plant.

Question 36

Phloem have tubes like xylem but there is one key difference between the tubes. What is this difference?

Answer 36

Phloem tubes cells are alive whereas xylem tube cells are dead cells.

Question 37

Phloem have ______ _______ which move dissolved ions in water up and down the phloem tubes but blocking other materials.

Answer 37

Sieve plates.

Question 38

Diffusion is?

Answer 38

The net movement of particles evenly throughout an area.

Question 39

The higher the difference in concentration, the _______ that diffusion will take place. What word finishes this sentence?

Answer 39

Faster

Question 40

Dissolved substances move in and out of your cells by diffusion across the ____ _______. What words finish the sentence?

Answer 40

Cell membrane.

Question 41

Give an example of a simple sugar that passes through the cell membrane by diffusion.

Answer 41

Glucose.

Question 42

Membranes that only allow some things to pass through are called ____-_________ membranes. Which word finishes this sentence?

Answer 42

Semi-permeable

Question 43

A dilute solution contains a ____ concentration of water and a low concentration of the solute. What word finishes the sentence?

Answer 43

High.

Question 44

A __________ solution contains a low concentration of water and a high concentration of the solute. What word finishes the sentence?

Answer 44

Concentrated.

Question 45

________, a special type of diffusion, is where only ______ moves from a dilute to a concentrated solution across a semi-permeable membrane. What two words finish the sentence?

Answer 45

Osmosis, water.

Question 46

If the concentration of solutes in a solution is the same as outside the solution, the solution is _________ to the outside. What word finishes the sentence?

Answer 46

Isotonic.

Question 47

If the concentration of solutes in a solution outside the cell is higher than the concentration internally, the solution is ____________ to the cell. What word finished the sentence?

Answer 47

Hypertonic.

Question 48

If the concentration of solutes in a solution outside the cell is lower than the concentration internally, the solution is ____________ to the cell.

Answer 48

Hypotonic.

Question 49

Plants require osmosis to maintain structure in the plant, the pressure in the cell is called _______. What word finishes the sentence?

Answer 49

Turgor.

Question 50

If a lot of water is lost from the cell, the cytoplasm and vacuole shrink and the cell membrane pulls away from the cell wall, this called _________ and occurs until an osmotic balance is restored. What word finishes the sentence?

Answer 50

Plasmolysis.

Question 51

Substances that transfer across a membrane by diffusion do so ____the concentration ________ as this is a passive process. What tow words finish the sentence?

Answer 51

Down, gradient

Question 52

Sometimes, cells need to uptake materials against the concentration gradient by _______ _________, this is an _____ process as it requires energy. Which words finish the sentence?

Answer 52

Active Transport, active process.

Question 53

When root hair cells uptake mineral ions, this is done by _______ _________ as they are dilute in the soil and this process goes against the __________ __________. Which words finish the sentence?

Answer 53

Active Transport, Concentration gradient.

Question 54

With a smaller surface area to volume ratio, _______ ________ is sufficient to exchange materials between surfaces. What two words finish the sentence?

Answer 54

Simple diffusion.

Question 55

As organisms become bigger their surface area to volume ratio gets smaller, and exchange of materials becomes more difficult. Give two ways this affects the organism.

Answer 55

1) Gas and food molecules can no longer reach every cell by simple diffusion, requiring more energy for active transport. 2) Metabolic waste cannot be removed fast enough from the cell to prevent poisoning.

Question 56

List and describe two adaptations animals have to help the diffusion rate by adjusting surface area to volume ratio.

Answer 56

1) Animals have an efficient blood supply moving substances away from the site of diffusion maintaining a high concentration gradient. 2) Animals are ventilated to ensure a high concentration gradient for gas exchange to be efficient.

Question 57

Give two places where these adaptations are found.

Answer 57

1) Alveoli in the lungs 2) Stoma in plant leaves.

Question 58

How do you make a slide for a microscope?

Answer 58

You add a thin specimen onto a slide, which is mounted in water or in a colouring. The specimen must be thin for light to pass through. The cover slip must be applied with a mounted needle to reduce air bubbles as they may be mistaken for cells. If a tissue is clear then a stain must be added to identify it. Onion have iodine solution applied to it since iodine element is a metal. Cheek cells use blue methylene.

Question 59

How do you focus a slide for a microscope?

Answer 59

Clip the slide onto the stage. Start with a low power as more cells can be seen and it has a wider field of view. It is also easier to focus. (X4) Firstly you use the course focusing wheel to increase the size of the stage until there is a sharp image. After, increase magnification with a fine focus to get a sharp image.

Question 60

How do you draw a diagram for a microscope experiment?

Answer 60

Firstly, write a title with the magnification (with a real microscope ) = eyepiece lens x objective lens. The diagram must be at least 1/2 of a page and the diagram must be proportionate, with parts labelled and to a suitable proportion to the image.

Question 61

How do you calculate the size of cells?

Answer 61

Image size = actual size x magnification. Actual size = Image size / magnification. E.g if the magnification = 100 and the image = 10 mm then the cell is 0.1mm.

Question 62

How many mm are in a cm?

Answer 62

10.

Question 63

How many micrometers are in one mm?

Answer 63

1000.

Question 64

How many nanometers are in a micrometer?

Answer 64

1000.

Question 65

What is an order of magnitude?

Answer 65

A multiplication of 10.

Question 66

If I go from 1 mm to 1nm, how many orders of magnitude am I going down by?

Answer 66

3.

Question 67

What is magnification?

Answer 67

How many times the image is by the real object.

Question 68

What is resolution?

Answer 68

The ability to distinguish 2 points that are very close together, separately.

Question 69

What is an organelle?

Answer 69

A sub-cellular structure with a specific function.

Question 70

If a scale bar tells you the actual size, how do you figure out the image size?

Answer 70

Measure the length of the scale bar.

Question 71

How do you measure the different levels of osmosis?

Answer 71

You measure the concentration in mol/dm3 in increments of 0.2 mol.

Question 72

What is an independent variable?

Answer 72

The variable that you change.

Question 73

What is the dependent variable?

Answer 73

The variable that you measure (or the output of the independent variable).

Question 74

In plant cells there is a permanent vacuole, what is in this permanent vacuole?

Answer 74

Cell sap

Question 75

Plant and algal cells also have a cell wall made of what?

Answer 75

Cellulose, which strengthens the cell wall.

Question 76

What are some examples of specialised cells in animals?

Answer 76

Sperm cells, nerve cells and muscle cells.

Question 77

How do cells specialise in plants?

Answer 77

Plant cells retain the ability to differentiate throughout their life.

Question 78

What are some examples of specialised cells in plants?

Answer 78

Root hair cells, xylem and phloem cells.

Question 79

How do animal cells differentiate?

Answer 79

Animal cells differentiate at an early stage.

Question 80

What is the equation for magnification?

Answer 80

Magnification = size of image / size of object

Question 81

What adaptations do nerve cells have?

Answer 81

They have many dendrites They have axons They have synapses

Question 82

What is the role of the dendrite in nerve cells?

Answer 82

They make connections to other nerve cells.

Question 83

What is the role of the axon in nerve cells?

Answer 83

Axons carry nerve impulses from one place to another, being very long.

Question 84

What is the role of the synapses in nerve cells?

Answer 84

They pass electrical impulses to another cell or betwee cells and a muscle using transmitter chemicals as they have many mitochondria.

Question 85

What adaptations do striated muscle cells have?

Answer 85

They have special proteins that slide over each other making fibres contract. They contain many mitochondria to transfer energy needed for chemical reactions to take place. They can store glycogen.

Question 86

Why is having glycogen stored in striated muscle cells useful?

Answer 86

It can be broken down and used in cellular respiration by mitochondria.

Question 87

What are the adaptations of sperm cells?

Answer 87

They have long tail and streamlined shape. The middle section contains many mitochondria. They have an acrosome. They have a large nucleus containing genetic information.

Question 88

What is the advantage of sperm cells having a long tail?

Answer 88

It whips from side to side and increases manoeuverability as a result.

Question 89

What is the advantage of having many mitochondria in sperm cells?

Answer 89

Energy can be released for all of the reactions occuring.

Question 90

What is the advantage of having an acrosome in sperm cells?

Answer 90

Digestive enzymes are stored which help break down the outer layers of the egg.