2. Organisation of the Organism

Question 1

Where is cytoplasm found and what does it contain?

Answer 1

Cytoplasm is found inside the cell and contains all the other cell structures

Question 2

What is the nucleus surrounded by and what does this do?

Answer 2

The large nucleus is surrounded by a nuclear membrane to separate it from the cytoplasm

Question 3

What is the cell wall made of in plant cells and what does it contain?

Answer 3

The cell wall is made of cellulose and surrounds the cell membrane in plant cells

Question 4

What are chloroplasts, where are they found, description?

Answer 4

Chloroplasts are organelles found in the cytoplasm that are packed with the pigment chlorophyll and so are green in colour

Question 5

What are vacuoles?

Answer 5

Vacuoles are large vesicles that take up a large part of the interior of plant cells

Question 6

What organelles are visible in almost all cells when looking at higher magnification?

Answer 6

• mitochondria
• ribosomes
• vesicles

Question 7

What can ribosomes be found in?

Answer 7

Ribosomes are tiny structures that can be free within the cytoplasm or attached to a system of membranes within the cell known as Endoplasmic Reticulum

Question 8

Where are vesicles found?

Answer 8

these are small circular structures found moving throughout the cytoplasm

Question 9

function of the nucleus

Answer 9

• contains genetic material in chromosomes which control how cells grow and work
• controls cell division

Question 10

cytoplasm function

Answer 10

• supports cell structures
• site of many chemical reactions
• contains water and many solutes

Question 11

cell membrane function

Answer 11

• holds the cell together

- controls substances entering and leaving the cell

Question 12

cell wall function

Answer 12

• gives the cell extra support and defines its shape

Question 13

chloroplasts function

Answer 13

• site of photosynthesis providing food for plants

- chlorophyll pigments absorb light energy needed for the reaction to occur

Question 14

vacuole function

Answer 14

• contains cell sap
• used for storage of certain materials
• also helps support the shape of the cell

Question 15

mitochondria function

Answer 15

• site of aerobic respiration providing energy for the cell
• cells with high rates of metabolism (carrying out many different cell reactions) will have significantly higher numbers of mitochondria than cells with lower numbers of reactions taking place in them

Question 16

ribosomes function

Answer 16

• site of protein production in protein synthesis

Question 17

vesicles function

Answer 17

• used to safely transport substances from one part of the cell to another

Question 18

what are specialised cells?

Answer 18

those which have developed certain characteristics in order to perform particular functions.

Question 19

What are the adaptations of cells controlled by?

Answer 19

These differences are controlled by genes in the nucleus

Question 20

How do cells specialise? What does it cause?

Answer 20

Cells specialise by undergoing differentiation: this is a process by which cells develop the structure and characteristics needed to be able to carry out their functions

Question 21

what are examples of specialised cells in animals?

Answer 21

• ciliated cell
• nerve cell
• red blood cell
• sperm cell
• egg cell (ovum)

Question 22

function of a ciliated cell

Answer 22

movement of mucus in the trachea and bronchi

Question 23

ciliated cells adaptations

Answer 23

extensions of the cytoplasm at the surface of the cell form hair-like structures called cilia which beat to move mucus and trapped particles up to the throat

Question 24

nerve cell function

Answer 24

conduction of impulses

Question 25

nerve cell adaptations

Answer 25

- long so that nerves can run to and from different parts of the body to the central nervous system - the cell has extensions and branches so that it can commute with other nerve cells muscles and glands - the axon (extension of cytoplasm away from the cell body) is covered with a fatty sheath which insulates the nerve cell and speeds up the nerve impulses

Question 26

red blood cell function

Answer 26

transport of oxygen

Question 27

red blood cell adaptations

Answer 27

- biconcave disc shape increases surface area for more efficient diffusion of oxygen - contains haemoglobin which joins with oxygen to transport it - contains no nucleus to increase amount of space available for haemoglobin inside cell

Question 28

sperm cell function

Answer 28

reproduction

Question 29

sperm cell adaptations

Answer 29

- the head contains the genetic material for fertilisation in a haploid nucleus (containing half the normal number of chromosomes) - the acrosome in the head contains digestive enzymes so that a sperm can penetrate an egg - the mid-piece is packed with mitochondria to release energy needed to swim and fertilise the egg - the tail enables the sperm to swim

Question 30

egg cell function

Answer 30

reproduction

Question 31

egg cell adaptations

Answer 31

- contains a lot of cytoplasm which has nutrients for the growth of the early embryo - haploid nucleus contains the genetic material for fertilisation - cell membrane changes after fertilisation by a single sperm so that no more sperm can enter

Question 32

What are examples of specialised cells in plants?

Answer 32

- root hair cell - xylem vessel - palisade mesophyll cell

Question 33

root hair cell function

Answer 33

absorption of water and mineral ions from soil

Question 34

root hair cells adaptations

Answer 34

- root hair increases surface area of cell to ensure maximum absorption of water and mineral ions - walls are thin to ensure water moves through quickly - no chloroplasts present

Question 35

xylem vessel function

Answer 35

conduction of water through the plant ; support of the plant

Question 36

xylem vessel adaptation

Answer 36

- no top and bottom walls between xylem vessels so there is a continuous column of water running through them - cells are dead without organelles or cytoplasm to allow free passage of water - their walls become thickened with a substance called lignin which means they are able to help support the plant

Question 37

palisade mesophyll cell function

Answer 37

photosynthesis

Question 38

palisade mesophyll cell adaptations

Answer 38

- column shaped to maximise absorption of sunlight and fit as many in a layer under the upper epidermis of the leaf as possible - contains many chloroplasts for maximum photosynthesis

Question 39

cells definition

Answer 39

basic functional and structural units in a living organism

Question 40

tissues definition

Answer 40

group of cells of similar structure working together to perform the same function

Question 41

organs definition

Answer 41

made from different tissues working together to perform specific functions

Question 42

organ systems definitions

Answer 42

groups of organs with related functions working together to perform body functions

Question 43

name 9 different organ systems

Answer 43

- shoot - root - digestive - circulatory - immune - respiratory - excretory - nervous - reproductive

Question 44

shoot system organs

Answer 44

leaf stem flower fruit

Question 45

shoot system tissue example

Answer 45

- epidermis mesophyll - xylem - phloem

Question 46

root system organs

Answer 46

- root | - tuber

Question 47

root system tissue example

Answer 47

- xylem - phloem - ground tissue

Question 48

digestive system organs

Answer 48

- oesophagus - stomach - small intestine - large intestine

Question 49

digestive system tissue example

Answer 49

- muscle - connective - nerve - epithelial

Question 50

circulatory system organs

Answer 50

- heart - veins - arteries

Question 51

circulatory system tissue example

Answer 51

- muscle - connective - nerve - epithelial

Question 52

immune system organs

Answer 52

thymus | spleen

Question 53

immune system tissue example

Answer 53

- bone marrow

Question 54

respiratory system organs

Answer 54

- trachea - bronchi - lungs

Question 55

respiratory system tissue example

Answer 55

- muscle - connective - epithelial

Question 56

excretory system organs

Answer 56

- liver - kidney - skin - lungs

Question 57

excretory system tissue example

Answer 57

- muscle - connective - nerve - epithelial

Question 58

nervous system organs

Answer 58

- brain | - spinal cord

Question 59

nervous system tissue example

Answer 59

- nerve

Question 60

reproductive system organs

Answer 60

- ovary - cervix - uterus - vagina - penis - testes

Question 61

reproductive system tissue example

Answer 61

- muscle - connective - nervous - erectile