Cells

Question 1

What is the average size of the diameter of a nucleus?

Answer 1

10μm

Question 2

What is the role of the cell membrane?

Answer 2

To control the passage of substances such as glucose and mineral ions into the cell, and also urea or hormones out of the cell.

Question 3

What is the average length of mitochondria?

Answer 3

1-2 μm

Question 4

What is the average diameter of mitochondria?

Answer 4

0.2-0.7 μm

Question 5

What is the role of the ribosomes?

Answer 5

To perform protein synthesis, providing all the proteins needed in the cell.

Question 6

What is the average length of a plant cell?

Answer 6

10-100 μm

Question 7

What do plant and algae cells have that animal cells don’t? Give 3 details.

Answer 7

Cell wall.
Chloroplasts-contains chlorophyll which absorbs light for making foot in photosynthesis.
Vacuole-keeps the cell rigid.

Question 8

How large are chloroplasts in length?

Answer 8

3-5 μm

Question 9

What’s the difference between eukaryotic and prokaryotic cells?

Answer 9

Eukaryotic cells have their genetic material enclosed in a nucleus, while the genetic material in prokaryotic cells have their genetic material outside the nucleus.

Question 10

What is the role of plasmids?

Answer 10

They code for features such as antibiotic resistance.

Question 11

What is the usual size of eukaryotic cells?

Answer 11

10-100 μm

Question 12

Prokaryotes are _______ times _______ compared to eukaryotic cells.

Answer 12

Roughly 100 times smaller.

Question 13

What is the job of a nerve cell?

Answer 13

To carry electrical impulses around the body of an animal. They provide a rapid communication system around the body.

Question 14

Give 3 adaptations of the nerve cells.

Answer 14

It has lots of dendrites to make connections to other nerve cells.

It has an axon, carrying the nerve impulse from one place to another.

The nerve endings or synapses are adapted to pass the impulses to another cell or between a nerve cell and a muscle in the body using special transmitter chemicals. They contain lots of mitochondria to provide energy to make the transmitter chemicals.

Question 15

What is the job of the muscle cells?

Answer 15

To move the bones of the skeleton.

Question 16

Draw a nerve cell and label it.

Answer 16

When you’re done, check on kerboodle.

Question 17

How can muscle cells move food in the body?

Answer 17

Smooth muscle cells form one of the layers of tissue in the digestive system and they contract to squeeze the food through the gut.

Question 18

Give 3 adaptations of striated muscle cells.

Answer 18

They contain special proteins that slide over each other making the fibres contract.

They contain mitochondria to transfer the energy needed for the chemical reactions that take place as the cells contract and relax.

They can store glycogen, a chemical that can break down and used in cellular respiration by the mitochondria to transfer the energy needed for the fibres to contract.

Question 19

Give 4 adaptations for a sperm cell.

Answer 19

It has a long tail whipping side to side to help the cell move through the reproductive system.

The middle section is full of mitochondria, which provides energy for the tail to work.

The acrosome stores digestive enzymes for breaking down the outer layers of the egg.

A large nucleus contains genetic information to be passed on.

Question 20

Draw a muscle cell.

Answer 20

When you’re done, check kerboodle.

Question 21

Draw a sperm cell.

Answer 21

When you’re done, check kerboodle.

Question 22

What is the role of a root hair cell?

Answer 22

They help plants, taking up water and mineral ions more efficiently.

Question 23

Where are root hair cells located and why is this good for mineral transportation?

Answer 23

They are relatively close to the xylem tissue, and the xylem tissue carries water and mineral ions up into the rest of the plant.

Question 24

How do mineral ions move into the root hair cell?

Answer 24

By active transport.

Question 25

Give 3 adaptations of a root hair cell.

Answer 25

They greatly increase the surface area available for water to move into the cell.

They have a large permanent vacuole that speeds up the movement of water by osmosis from the soil across the root hair cell.

They have many mitochondria that transfer the energy needed for active transport of mineral ions into the root hair cells.

Question 26

Draw a diagram of a root hair cell.

Answer 26

When you’re done, check kerboodle.

Question 27

What is the function of a xylem cell?

Answer 27

Forming part of xylem tissue which carries water and mineral ions through the plant.

Question 28

Give 2 adaptations for the xylem cell.

Answer 28

When the cells die, they form long, hollow tubes that allow water and mineral ions to move through from one end of the plant to the other.

The spirals and rings of lignin in the xylem cells make them very strong and help them withstand the pressure of water moving through the plant.

Question 29

What does the phloem cell do?

Answer 29

Forms part of the phloem, carrying food made by photosynthesis around the body of the plant.

Question 30

Give 2 adaptations of the phloem cell.

Answer 30

The cell walls between the cells break down to form special sieve plates. These allow water carrying dissolved food to move freely up and down the tubes to where it’s needed.

Phloem cells lose a lot of their internal structures but they are supported by companion cells that help to keep them alive. The mitochondria of the companion cells transfer the energy needed to move dissolved food up and down the plant in the phloem.

Question 31

Draw a diagram of a xylem cell.

Answer 31

When you’re done, check kerboodle.

Question 32

Draw a diagram of a phloem cell.

Answer 32

When you’re done, check kerboodle.

Question 33

What is the net movement?

Answer 33

The overall movement.

Question 34

Explain the movement of gas exchange.

Answer 34

The oxygen needed for respiration passes from air in the lungs into red blood cells by diffusion.

Oxygen can then move from the blood cells to cells of the body where it is needed. Carbon dioxide goes the other way, diffusing out and back into the red blood cells and then the lungs.

Question 35

Explain the movement of urea that works with diffusion.

Answer 35

The urea passes from the liver cells into the blood plasma and is excreted by the kidneys.

Question 36

If the concentration of solutes inside the cell is higher than the outside, it is…

Answer 36

Hypotonic

Question 37

If the concentration of solutes inside the cell is lower than the outside, it is…

Answer 37

Hypertonic

Question 38

If the concentration of solutes inside the cell is is the same than the outside, it is…

Answer 38

Isotonic

Question 39

If the outside of the cell is far more concentrated than the cell…

Answer 39

Lots of water particles move in by osmosis, and the the cell swells and bursts.

If the other way round, the cell shrivels up and can no longer survive.

Question 40

What is turgor pressure?

Answer 40

When water moves into plant cells by osmosis, causing the vacuole to swell, pressing the cytoplasm against the plant cell wall.

This keeps the plant rigid and firm.

Question 41

What concentration do plants rely on?

Answer 41

The fluid surrounding the cells should be hypertonic to the inside of the cell.

Question 42

If outside the cells is hypertonic to the cell contents…

Answer 42

Water leaves the cells by osmosis. The plant cell becomes flaccid.

Question 43

If too much water is lost in plant cells…

Answer 43

The cell becomes plamolysed. The osmotic balance must be restored to allow the cell to survive.

Question 44

What’s the difference between osmosis and active transport?

Answer 44

The particles move against a concentration gradient, and require energy from respiration to function.

Question 45

Explain the movement of active transport of glucose.

Answer 45

The concentration of glucose in the blood is kept steady, so sometimes when the concentration is higher outside, the glucose moves from the gut into the bloodstream.