Chapter 1:Cell structure and transport

Question 1

What are chromosomes? where are they found? And what do they contain?

Answer 1

The chromosomes carry your Genes which hold the information for an entirely new you
They are found in the nucleus

Question 2

How many micrometers are in 1mm

Answer 2

1000um [ weird u ]

Question 3

How many nanometers are in 1um

Answer 3

1000nm so 0.000,000,001m

Question 4

How do you work out the magnification from a microscope using the formula?

Answer 4

Magnification = size of image / size of real object

Question 5

How to work out the size of the real object from the formula for microscopes?

Answer 5

Real object = size of image/ magnification

Question 6

Describe the formula triangle for microscope calculations

Answer 6

Image size at top
Magnification bottom left
Size of real object bottom right

Question 7

Name the parts of an animal cell

Answer 7

Nucleus, cell membrane, chromosomes, ribosomes, cytoplasm, mitochondria

Question 8

Name the parts of a plant cell

Answer 8

Nucleus, cell membrane, chloroplast,cytoplasm, cell wall, vacuole , mitochondria, ribosomes

Question 9

Name the parts of the animal and plant cells which are the same

Answer 9

The cell membrane, cytoplasm, ribosomes, mitochondria, nucleus

Question 10

Describe the nucleus

Answer 10

It controls all the activities within the cell and is surrounded by the nuclear membrane, it is around 10nm

Question 10

Describe the cytoplasm

Answer 10

A liquid gel in which the organelles are suspended and where most of the reactions needed for life take place.

Question 11

Describe the cell membrane

Answer 11

Controls the passage of substances such as glucose and mineral int the cell. It also controls the movement of substances such as urea and hormones out of the cell

Question 12

Describe mitochondria

Answer 12

Structure within the cytoplasm where aerobic respiration takes place releasing energy for the cell

Question 13

Describe ribosomes

Answer 13

The place where proteins syntheis takes place, making all the proteins needed in the cell

Question 14

Describe chloroplasts

Answer 14

They are within the green parts of the cell, they are this colour because they contain the substance chlorophyll. Chlorophyll absorbs light so the plant can make food by photosynthesis.

Question 15

Describe vacuole

Answer 15

It is a space inside the cytoplasm filled with cell sap, this is important to keeping the cell rigid to support the plant

Question 16

What is an example of a eukaryotic cell?

Answer 16

An example of eukaryotic cells are human and plant cells

Question 17

An example of a prokaryotic cell

Answer 17

Bacteria all bacteria are prokaryotes

Question 18

Describe a eukaryotic cell

Answer 18

They all have a cell membrane, cytoplasm, and genetic material enclosed within the nucleus

Question 19

Describe a prokaryotic cell

Answer 19

Prokaryotic cells consist of cytoplasm, a cell membrane no surrounded by a cell walk, the DNA is not contained within the nucleus it forms a single DNA loop they also contain one or two more rings of DNA called plasmid

Question 20

State a use for the flagella

Answer 20

It is a long protein strain that lashes around it is used to move the bacteria around

Question 21

Define a specialised cell

Answer 21

A specialised cell is a cell which forms sub cellular structures to aid it in carrying out a particular function.

Question 22

State one adaptation of a nerve, muscle and sperm cell and how it aids the cell.

Answer 22

Nerve cell- they have lots of dendrites to make connections to other nerve cells
Muscle cell- they contain special proteins which slide over each other making the fibres contract
Sperm cell- it uses a flagella to move through the female reproductive system to the egg

Question 23

Give three examples of specialised cells in animals.

Answer 23

Nerve cells, muscle cells and sperm cells

Question 24

Give 1 example of an adaptation of a plant cell and what it does to aid the cell

Answer 24

Root hair cell- it has a large surface area increasing the amount of water that can move into the cell Photosynthetic cell- they contain specialised cells called chloroplasts which trap light to be turned into energy Phloem-the cell walls between the cells break down and form sieve like structures it allows water carrying dissolved food to move freely up the stem Xylem-the cells are alive t first but lignin build up within the pants killing them and forming long hollow tubes for water and minerals to travel up nd down

Question 25

Define diffusion

Answer 25

Diffusion is the movement of particles in an area of high concentration moving in an area of low concentration down a concentration gradient

Question 26

Give an example of things that affect diffusion

Answer 26

Temperature. Surface area. The difference in concentration

Question 27

An example of diffusion in the human body

Answer 27

Dissolved substances such as glucose and urea and gasses move in and out of cells by diffusion

Question 28

What happens to an animal cell if the concentration changes dramatically?

Answer 28

It will be damaged

Question 29

If the concentration of solutes in the solution outside the cell is the same as the internal concentration what state would the cell be in?

Answer 29

The solution is isotonic to the cell. Normal

Question 30

If the concentration of solutes in the solution outside the cell is higher than the internal concentration the solution is?

Answer 30

Hypertonic to the cell. Shrivelled

Question 31

If the concentration of solutes in the solution outside the cell is lower than the internal concentration the solution is?

Answer 31

Hypotonic to the cell. Burst

Question 32

Name the three states a cell can be in via osmosis and what it means for them to be in that state

Answer 32

Isotonic, normal Hypotonic, burst Hypertonic, shrivelled

Question 33

What is osmosis - define.

Answer 33

Osmosis is a special case of diffusion. It is the movement of water from a dilute to a more concentrated solute solution through a partially permeable membrane that allows water to pass through

Question 34

What is the point of osmosis in plants

Answer 34

It keeps the cell turgid, strong

Question 35

What is active transport?

Answer 35

It moves substances against the concentration gradient from a less concentrate solution to a more concentrate solution.

Question 36

Active transport works only if there is...

Answer 36

Energy is required for active transport to function

Question 37

Give an example of active transport in plants

Answer 37

It allows root hair cells to absorb water mineral ions required for growth from very dilute solution against the concentration gradient

Question 38

Give an example of active transport in humans

Answer 38

Sugar molecule used for cell respiration to be absorbed from lower concentrations in the gut into the blood where the concentration of sugar is higher.

Question 39

Describe two adaptations of an effective exchange surface

Answer 39

Having a large surface area where exchange can take place | Having a thin membrane or being thin to provide a short diffusion path.

Question 40

Describe three ways that a sperm cell is adapted

Answer 40

It is streamline Has a flagella Contains chromosomes that provide energy

Question 41

Give 2 ways that stem cells could be used to cure disease

Answer 41

The stem cells in bone marrow could help someone with faulty blood cells Embryotic stem cells could be used to produce insulin producing cells for diabetics

Question 42

Name 3 things that can diffuse through cell membranes and two that can't

Answer 42

Glucose oxygen and water can | Proteins and starch can't

Question 43

What type of molecules move by osmosis

Answer 43

Water

Question 44

What is the main difference between active transport and diffusion.

Answer 44

Active transport requires energy. Remember the sheep pen.

Question 45

Give three adaptations of exchange surfaces that increase efficiency of diffusion

Answer 45

They will have a large surface area Have a good blood supply Have thin walls for quick diffusion

Question 46

Explain how leaves are adapted to maximise the amount of carbon dioxide going into the cells

Answer 46

They are flat increasing the area for gas exchange | The walls of the cells act as another exchange surface