Structure and functions in living organisms

Question 1

Name the organelles in an animal cell

Answer 1

-Nucleus
-Cell membrane
-Cytoplasm
-Mitochondria
-Ribosomes

Question 2

Name the organelles found in a plant cell

Answer 2

-Nucleus, cell membrane, cytoplasm, mitochondria, ribosomes
+
-cell wall, vacuole, chloroplasts

Question 3

List the following in size order:
-Cells, Organs, Organelles, Systems, Tissues

Answer 3

-Organelles, Cells, Tissues, organs and systems

Question 4

What is the function of the nucleus

Answer 4

Stores DNA and co-ordinates the cell’s processes

Question 5

What is the role of the cytoplasm

Answer 5

Jelly-like fluid that supports and suspends the cell organelles

Question 6

What is the role of cell membrane

Answer 6

Regulates the movement of substances in and out of the cell.

Question 7

What is the role of the cell wall

Answer 7

Gives the cell structure and shape, prevents plant cells from bursting when it absorbs water.

Question 8

What is the role of the mitochondria

Answer 8

This is where respiration takes place

Question 9

What is the role of the chloroplasts

Answer 9

This is where photosynthesis occurs

Question 10

What are stem cells?

Answer 10

-Stem cells are unspecialised cells
-They have the ability to differentiate into many cell types.

Question 11

Where are stem cells found?

Answer 11

-Bone marrow
-Many organs
-Eyes
-Umbilical cord
-Embryo (not adult stem cells)

Question 12

Where are stem cells found in plants?

Answer 12

In the stem.

Question 13

What is differentiation?

Answer 13

When cells can turn on/off different genes, by translation or transcription of genes.

When a cell changes to become specialised for it’s job

Question 14

How are cells specialised?

Answer 14

They have different structures to suit their different functions

Question 15

How do stem cells split?

Answer 15

They divide by mitosis frequently.

Question 16

What can stem cells be used for?

Answer 16

To cure diseases and they can differentiate into any cell type.

Question 17

What are issues with using stem cells for curing disease?

Answer 17

-Stem cells grown in labs can become contaminated with a virus making the person sicker.

-Some people are against stem cell research as an embryo can be considered as a human life.

Question 18

What elements are present in carbs?

Answer 18

Carbon, Hydrogen and oxygen.

Question 19

What elements are present in proteins

Answer 19

Carbon, Nitrogen, Hydrogen and Oxygen

Question 20

What elements are in lipids

Answer 20

Carbon, Hydrogen and oxygen.

Question 21

What are proteins made up of

Answer 21

Long chains of amino acids

Question 22

What are carbs made up of

Answer 22

Starch and glycogen are made up of lots of simple sugars like glucose or maltose.

Question 23

What are lipids made up of

Answer 23

They are built from fatty acids and glycerol.

Question 24

How are plants adapted for photosynthesis?

Answer 24

Leaf cells contain chloroplasts which contain chlorophyll which absorbs sunlight and carries out photosynthesis.

Question 25

What are magnesium ions needed for?

Answer 25

They are needed for chlorophyll

Question 26

What are nitrate ions needed for?

Answer 26

Amino acids

Question 27

What is the role of the mouth?

Answer 27

-Salivary glands in the mouth produce amylase enzyme in the saliva -Teeth break down food

Question 28

What is the Oesophagus

Answer 28

-The muscular tube that connects the mouth and stomach.

Question 29

What is the alimentary canal?

Answer 29

The gut

Question 30

Role of the liver

Answer 30

-Where bile is produced

Question 31

Role of Gall Bladder

Answer 31

-Where bile is stored

Question 32

What is Bile?

Answer 32

Bile is an alkaline that neutralises stomach acid so the enzymes in the small intestine can work at optimum pH. -Bile also emulsifies fats increasing speed of digestion.

Question 33

What is the role of the small intestine?

Answer 33

-Produces protease, amylase and lipase enzymes to complete digestion -This is also where the nutrients are absorbed out of the gut into the body

Question 34

What are the 2 parts of the small intestine?

Answer 34

The first bit is the duodenum and the last part is ileum.

Question 35

Role of Pancreas

Answer 35

-Produces protease, amylase and lipase enzymes. It releases these into the small intestine.

Question 36

Role of the Large Intestine

Answer 36

-Where excess water is absorbed from the food.

Question 37

Role of the rectum?

Answer 37

-The last part of the large intestine -Where the faeces are stored

Question 38

Role of the stomach`

Answer 38

-Pummels the food with its muscular walls -It produces pepsin -Produces hydrochloric acid to kill bacteria and give protease enzyme to work.

Question 39

How is the small intestine adapted for absorption of food?

Answer 39

-Large surface area for absorption because walls of small intestine are covered in millions of villi. -Villi has a permeable layer of surface cells and a very good blood supply to assist quick absorption.

Question 40

Where does gas exchange occur in humans?

Answer 40

The alveoli

Question 41

How are alveoli specialised for gas exchange?

Answer 41

-Very large surface area -Moist lining for gases to dissolve in -One cell thick -Permeable walls

Question 42

Role of the intercostal muscles and diaphragm

Answer 42

They contract during breathing in and relax during exhalation. (Diaphragm moves up when relaxing)

Question 43

Thorax

Answer 43

The top part of the body seperated by the diaphragm

Question 44

Intercostal muscles

Answer 44

They run inbetween the ribs

Question 45

Rib-cage

Answer 45

Protect the vital organs such as lungs

Question 46

Trachea

Answer 46

This is where the air that is breathed in goes

Question 47

Bronchi

Answer 47

Tubes that go from trachea to each lung.

Question 48

Bronchioles

Answer 48

Small tubes that are connected to alveoli and bronchus

Question 49

Alveoli

Answer 49

This is where gas exchange happens, small bags connected to bronchioles.

Question 50

What are the lungs surrounded by

Answer 50

Pleural membranes

Question 51

How can smoking cause coronary heart disease

Answer 51

-Carbon monoxide in cigarette smoke reduces the amount of oxygen the blood can carry -Blood pressure increases, damaging artery walls leading to blood clots in the artery.

Question 52

How can smoking cause cancer

Answer 52

Because Tobacco smoke contains carcinogens, chemicals that lead to cancer.

Question 53

How can smoking cause diseases like emphysema

Answer 53

-Smoking damages the walls inside the alveoli reducing the SA for gas exchange.

Question 54

Effect of Tar on the body from smoking

Answer 54

Tar damages the cilia in the lungs and trachea, leading to the build up of mucus leading to illness like chest infection

Question 55

Why do multicellular organisms need a variety of substances to live

Answer 55

The cells in all living organisms need a variety of substances to live, such as water, minerals and sugars. They also need to get rid of waste substances

Question 56

Why do unicellular organisms rely on diffusion?

Answer 56

The substances can diffuse directly into and out of the cell across the cell membrane. The rate of diffusion is quick as distance is short.