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Year 9 Biology exam B1 and B2 > B1 and B2 > Flashcards

B1 and B2 Flashcards

(55 cards)

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1
Q

What is the formula for magnification?

A

Magnification = image size/real size

Image size= real size x magnification

Real size= image size/magnification

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2
Q

What is the magnification of a microscope that sees a 0.4 mm cell that is seen as an 80 mm image?

A

x 200

(80/0.4)

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3
Q

What is the size of the image produced when a 0.1mm cell is magnified by 400?

A

40 mm

(0.1 X 400)

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4
Q

A nucleus is measured 0.005 mm in diameter. How many micrometers is this?

A

5 micrometers

(0.005 x 1000)

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5
Q

Arrange thise structures in order of size, largest first:

bacterium

liver cell

nucleus

ribosome

A
  1. liver cell
  2. nucleus
  3. bacterium
  4. ribosome
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6
Q

What are the parts of the animal cell?

A
  1. Nucleus
  2. Cytoplasm
  3. Cell membrane
  4. Mitchondria
  5. Ribosomes
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7
Q

What is the function of the nucleus?

A

It controls the activities of the cell and contains the genetic material

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8
Q

What is the function of the cytoplasm?

A

This is where most of the chemical reactions take place.

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9
Q

What is the function of the cell membrane?

A

It controls the passage of stubstances into and out of the cell.

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10
Q

What is the function of the mitochondria?

A

This is where aerobic respiration takes place. (energy is made)

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11
Q

What is the function of the Ribosomes?

A

This is where proteins are synthesesised (made).

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12
Q

What are the parts of the plant cell?

A

All the parts of the animal cell +

  1. Cell wall
  2. Permanent vacuole
  3. Chloroplasts (apart from root cells)
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13
Q

What is the function of the cell wall?

A

It is made out of cellulose which strengthens the cell

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14
Q

What is the function of the permanent vacuole?

A

It is fill with cell sap which supports the plant.

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15
Q

What is the functions of the chloroplasts?

A

They absorb light to make food (glucose) by photosynthesis.

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16
Q

Why do root cell have no chlorplasts?

A

Because the roots don’t receive any sun light

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17
Q

What are eurokaryotic cells?

A

plant, animal and fungal cells

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18
Q

What are prokaryotic cells?

A

Bacteria cells

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19
Q

What are the difference between the two types of cell?

A

Prokaryotic cells are:

  1. simpler and smaller in size
  2. no nucleus with genetic material
  3. genetic material is in DNA loops called plasmids
  4. no mitochondria or chloroplasts
  5. They come in different shapes (spiral, rod, spherical)
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20
Q

What are the parts of a typical bacterial cell?

A
  1. Cell wall
  2. cytoplasm
  3. Plasmid DNA
  4. Chromosomal DNA
  5. Flagella
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21
Q

What is the function of Flagella?

A

They are tail like structure that move the bacteria

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22
Q

Where is DNA found in a bacterium?

A

Floating free in the cytoplasm

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23
Q

Why are plasmids useful for scientists?

Study These Flashcards
A

They are used in genetic engineering because the can be inserted into bacteria.

24
Q

What developed first Prokaryotic or eurkaryotic cells?

Study These Flashcards
A

Prokaryotic because they are simpler

25
What are examples of specialised cells?
Red blood cell, white blood cell, neuron, sperm cell, muscles cells, root hair cells, palisade leaf cell, ciliated hair cell
26
How is a red blood cell adapted to its function?
Function: **to carry blood round the body** Adaptation: **no nucleus, large surface area**
27
How are Neurons (nerve cells) adapted to their function?
Function: to **carry electrical impulses round the body** Adaptation: **very long so it can reach far part of the body**
28
How are sperm cells adapted to their function?
Function: to **reach and fertilise the female egg** Adaptation: **Flagellum (tail)** for swimming, **many mitochondria** for extra energy
29
How are muscle cells adapted to their function?
Function: to **expand and contract to move the body** adaptations: **lots of mitochondria** to help release energy
30
How are root hair cells adapted to their function?
Function: to **absorb water and mineral ions** Adaptation: **Large surface area**, **thin cell wall,** **many mitochondria** to help active transport
31
How are white blood cells adapted to their function?
Function: to **fight disease by killing bacteria and releasing antibodies** Adaptation: can **change shape**, allowing them to engulf and **destroy** **microbes**
32
How are palisade leaf cells adapted to their function?
Function: to **capture light energy for photosynthesis** Adaptations: **many chloroplasts** to help photosynthesis**, large surface area** to absorb lots of light
33
How is a ciliated hair cell adapted to its function?
Function: to **prevent lung damage** Adaptation: **tiny hairs** to catch and move mucus and bacteria
34
What is diffusion?
Movement of particles in and out of cells **from area of high** concentration **to low** concentration
35
Where does diffusion happen in animals?
**Lungs** (gas exchange O2/CO2) **small intestines** (digested food into blood)
36
Where does diffusion happen in plants?
**In and out of leaf** (gas exchange CO2/O2) ## Footnote **water in roots**
37
What factors increase the rate of diffusion?
1. increase in temperature 2. larger, thinner surface area 3. increase in concentration gradient
38
What is Osmosis?
The **movement of water particles** **from** area of **high** **to low** concentration **across a semipermeable membrane**
39
What is active transport?
The movement of particles **from and area of low** **to high concentration requiring energy** from respiration.
40
Why is active transport needed?
1. in **plants roots to absorb minerals from the soi**l 2. for animals to allow **sugar molecules to be absorbed from the gut into the blood**
41
A person opens a bottle of perfume. Why do people in the room smell it faster on a warm day?
The perfume diffuses faster on a warm day
42
What is required for substances to be absorbed against a concentration gradient?
Energy from respiration
43
What are chromosomes? Where are they found?
1. Chromosomes are made of DNA and carry genes. 2. They are found **in pairs** (one from each parent) **in the nucleus.**
44
What are genes?
Different genes contain the **code to make different proteins** and so **control** the development of **different characteristics**, for example eye colour
45
How many chromosomes are there in humans?
46 (23 pairs)
46
How do cells grow?
They go through a **series of changes** involving **growth and division** called the **cell cycle.**
47
What is mitosis?
When the cell divides into two identical cells.
48
What are the stages of mitosis?
1. Each chromosome copies itself. 2. One set of chromosomes is pulled to each end of the cell. 3. The nucleus divides. 4. The cytoplasm and cell membrane divide to form two identical cells.
49
Why is mitosis important?
It **makes new cells** for: 1. **growth** and development of organisms 2. **repair** of damaged tissues 3. **asexual production**
50
What is a stem cell?
Cells that are undifferentiated - they have not yet become specialised.
51
What kind of stell cells are there?
1. Embryonic stem cells - found in human embryos, they can make all types of cells, 2. Adult stem cells- found in organs and tissues e.g. bone marrow - they can make only certain types of cells, their capacity to divide is limited
52
What are stem cells used for?
IN HUMANS: 1. Treating medical conditions e.g. diabetes 2. Replace damaged cells IN PLANTS: 1. Rare species can be cloned to protect them from extinction 2. large numbers of plants with special features such as disease resistance can be made
53
Why are some people concerned about using stem cells from embryos?
1. There may be af risk such as the transfer of an infection. 2. Religous or ethical reasons.
54
What are the advantages of using therapeutic cloning?
Stem cells from the cloned embryo will not be rejected by the patient's body, so could be useful in treating diseases
55
Where are stem cells found in plants?
In meristems.

Year 9 Biology exam B1 and B2 (1 decks)

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