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Flashcards in paper 1 Deck (53)
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1
Q

Describe what is meant by the term eukaryotic

A

A eukaryote is an organism whose cells contain a nucleus within a membrane.

2
Q

What 3 organelles are present in plant cells but not in animal cells?

A

cell wall, chloroplasts, vacuole

3
Q

What do bacterial cells have instead of a nucleus?

A

The DNA is found in the nuceloid, a region with no membrane, or as a plasmid, a small circle of extra genetic information, floating right in the cytoplasm, the fluid that fills the cell.

4
Q

What is the equation to calculate magnification?

A

magnification = image size / actual size

5
Q

What is the equation to calculate image size?

A

magnification = image size / actual size

6
Q

Why do you stain cells before looking at them under the microscope?

A

To enhance visualization of the cell or certain cellular components

7
Q

Define the term specialised cell

A

cells that have developed certain characteristics to perform a particular function

8
Q

What are the 6 types of specialised cells you need to know?

A

Sperm cells, nerve cells, muscle cells, root hair cells, phloem and xylem cells

9
Q

How many chromosomes are there in a human cell?

A

46

10
Q

What are the 3 main stages of the cell cycle?

A

Growth, DNA replication, mitosis

11
Q

Describe the individual steps in mitosis

A

1) The chromosomes line up at the center of the cell
2) The 2 arms are pulled apart to opposite sides of the cell
3) The nucleus divides
4) Each set of chromosomes becomes the new nucleus of the cell
5) The cytoplasm and cell membrane divide
6) A new cell is created

12
Q

What is a stem cell?

A

Cells that have not yet differentiated into different types of cells

13
Q

Why are there ethical issues surrounding stem cells?

A

Some people think embryos shouldn’t be researched because they could be human life.

14
Q

What are meristem cells used for in plants?

A

A meristem is the tissue in most plants containing undifferentiated cells (meristematic cells), found in zones of the plant where growth can take place.

15
Q

Define the term diffusion

A

Diffusion is the spreading out of cells from an area of high concentration to lower concentration

16
Q

Define the term osmosis

A

Osmosis it the movement of water molecules across a partially permeable membrane from a high concentration to lower concentration

17
Q

Define the term active transport

A

Substances being absorbed from a lower concentration to a higher concentration - against the concentration gradient.

18
Q

Give 2 examples of where active transport occurs

A

Root hair cells and in blood

19
Q

How can you observe the effect of sugar solutions on plant tissues

A

Using a microscope

20
Q

How are the alveoli adapted for gas exchange

A

Very thin, loads of them, large surface area

21
Q

Define the term tissue

A

A tissue is a group of similar cells that work together to carry out a function

22
Q

What is an catalyst

A

A catalyst is a substance which increases the speed of a reaction, without being used up or changed

23
Q

Describe the lock and key model

A

Every enzyme has an active site with a unique shape. The substrate involved with the enzyme has to fit that specific shape.

24
Q

What enzyme breaks down proteins

A

Protease

25
Q

How would you test for a protein

A

Biuret test

26
Q

What would a positive result be for the iodine test

A

The colour of the solution would change from a browny-orange to a black or blue.

27
Q

How would you test for a lipid

A

The Sudan III test or ethanol

28
Q

What would a positive result be for the benedict’s test

A

The solution would turn from a blue colour to green, yellow or brick red.

29
Q

Describe the path of a red blood cell in the left side of the heart

A

The blood would enter the left atrium via the pulmonary vein, be pumped out of the left ventricle through the aorta back to the body

30
Q

Describe the structure of an artery

A

Strong, elastic, muscly, travel away from the heart, carry high pressure blood

31
Q

Describe the structure of a vein

A

Thinner walls, have valves, travel towards the heart, low pressure blood

32
Q

Explain the functions of the 4 components of blood

A

Red blood cells carry oxygen, white blood cells fight infection, platelets help blood clot, plasma carries all the blood

33
Q

What is a coronary artery

A

An artery that supplies the heart muscle with blood

34
Q

How can you reduce the risk of coronary heart disease

A

Eat healthy, exercise

35
Q

Give 3 examples of both communicable and non-communicable diseases

A

1) chicken pox, flu, cold

2) cancer, parkinsons, diabetes

36
Q

What is a non-cancerous tumor called

A

Benign

37
Q

Why are malignant tumors life threatening

A

They get into healthy tissues and form secondary tumours

38
Q

Describe the function of a xylem cell

A

transport water from roots to leaves

39
Q

What is translocation

A

Movement from one place to another

40
Q

Describe how viruses reproduce

A

The virus injects its nucleic acid into the cell. The nucleic acid takes over the normal operation of the host cell and produces multiple copies of the virus’s protein coat and nucleic acid.

41
Q

What are 2 types of bacterial diseases and how are they passed on

A

Salmonella through raw food, gonorrhea though unprotected sex

42
Q

What is malaria spread by

A

Malaria is spread by mosquitos which carry the Plasmodium protist.

43
Q

How does our immune system attack pathogens?

A

Phagocytes and lymphocytes kill the pathogens

44
Q

How do vaccinations protect from future infection

A

the wbc’s already have antibodies against the illness

45
Q

What are 3 drugs that come from plants and what plants do they come from

A

Aspirin from willow bark, digitalis from foxgloves, opium from poppys

46
Q

How do new drugs become available

A

They are tested loads

47
Q

What is the equation for photosynthesis

A

carbon dioxide + water (light) —> glucose + oxygen

48
Q

How do plants use glucose

A
  • to make cell walls
  • turned into starch and stored
  • for respiration
49
Q

What is metabolism

A

the chemical processes that occur within a living organism in order to maintain life.

50
Q

What are the equations for anaerobic respiration in humans and plants

A

For humans - glucose -> lactic acid

for plants - glucose → ethanol + carbon dioxide

51
Q

glucose symbol

A

c6h12o6

52
Q

What do mitochondria do?

A

Release energy

Aerobic respiration

53
Q

What do ribosomes do?

A

Make protein