Chapter B3 Organisation And The Digestive System

Question 1

What is a tissue?

Answer 1

A group of cells with similar structure and function working together

Question 2

What is an example of human body tissue?

Answer 2

Epithelial tissue- covers outside of your body and your organs
Glandular tissue- contains secretory cells that can release and produce substances such as hormones and enzymes

Question 3

What is an organ?

Answer 3

A collection of tissues, working together to form a specific function

Question 4

Give an example of an organ?

Answer 4

Stomach

Pancreas

Question 5

What is an organ system?

Answer 5

A group of organs working together to perform a specific function

Question 6

Name an organ system in the human body

Answer 6

Digestive system
Circulatory system
Gas exchange system

Question 7

What is an organism made up of?

Answer 7

A multicellular organism is made from groups of organ systems

Question 8

What are the main organs where food is digested?

Answer 8

Stomach and small intestine

Question 9

What are carbohydrates broken down by?

Answer 9

Carboghydrases like amylase

Question 10

Where is amylase found?

Answer 10

The salivary glands and the pancreatic fluid

Question 11

What is a lipid molecule?

Answer 11

Consists of glycerol attaches to three molecules of fatty acid

Question 12

What is a lipid digested by?

Answer 12

Liphase

Question 13

What helps to speed up the digestion of lipids?

Answer 13

Bile- it is an alkaline which allowes it to neutralise the stomach acid, creating alkaline in the small intestine

Question 14

Where is bile stored and made?

Answer 14

Gall bladder

Question 15

Why do humans have a digestive system?

Answer 15

To break our food molecules down so that it can be absorbed

Question 16

What are proteins broken down by?

Answer 16

Proteases such as pepsin

Question 17

What are carbohydrates made up of and what is an example of a carbohydrate?

Answer 17

Carbohydrates are made up of simple sugars

Example is bread, potatoes, pasta and rice

Question 18

What are lipids made up of and give an example of a lipid?

Answer 18

Lipids are made up of glycerol and three molecules of fatty acids

Example is rich food such as olive oil, butter, margarine and cheese.

Question 19

What are proteins made up of and what is an example of a protein?

Answer 19

Proteins are made up of amino acids

An example is chicken or fish

Question 20

What do carbohydrates do?

Answer 20

Provide us with sustainable energy that is long lasting

Question 21

What do lipids do?

Answer 21

Source of energy and an important energy store- important for cell membranes and nervous system

Question 22

What do proteins do?

Answer 22

Used to build up cells and tissues of your body, and are also the basis of your enzymes.

They act as antibodies, hormones like insulin, and enzymes

Question 23

Basic process of digestion for lipids?

Answer 23

Mouth - teeth chew
Tongue- rolls food into a ball
Oesophagus- pushes food to stomach by peristalsis
Stomach- produces HCL which kills bacteria on food and creates acidic environment for enzymes to work
Small intestine- liquid bile is produced which emulsifies the fat. This neutralises the stomach acid. Pancreatic lipase are also present.
Large intestine- excess water is removed and taken to blood stream
Anus- undigested food exits by excretion

Question 24

What does emulsifies mean?

Answer 24

Breaks up the fat into smaller droplets

Question 25

Basic process of digestion of carbohydrates?

Answer 25

Mouth- salivary glands produce amylase- turns starch into maltose. Teeth grind the food. Tongue- rolls into ball Oesophagus- pushes food to stomach by peristalsis Stomach- kills bacteria on food and creates acidic environment Small intestine- pancreatic amylase breaks remaining starch to maltose. Enzymes then turn this into glucose. Intestinal walls also produce maltase, which turns maltose to glucose. Large intestine- excess water is removed. Remaining starch is excreted.

Question 26

How does the body prevent constipation?

Answer 26

Takes the water from the undigested food

Question 27

Basic process of digestion of proteins?

Answer 27

Mouth- teeth chew food Tongue- rolls into ball Oesophagus m- pushes to stomach by peristalsis Stomach- proteases are released, kills bacteria on food and creates acidic environment Small intestine- releases protease that breaks down the proteins into amino acids Large intestine- excess water is removed and excreted through the anus

Question 28

What is a catalyst?

Answer 28

Speeds up chemical reactions

Question 29

What do enzymes react with?

Answer 29

A substrate

Question 30

What is an enzyme?

Answer 30

A large protein molecule

Question 31

The long chains of amino acids are folded to have unique shapes- why?

Answer 31

To produce a molecule that can bond to the active site of a specific substrate

Question 32

What is the lock and key theory?

Answer 32

The substrate of the reaction fits with an enzyme so it can be catalysed, like a lock and key

Question 33

Explain what an enzyme does

Answer 33

Joins with a substrate which fits into its specific active site Then binds to create an enzyme substrate complex The substrate then splits into new products and the enzyme is ready to use again

Question 34

Do enzymes change a reaction?

Answer 34

No they just make it faster

Question 35

What do enzymes control?

Answer 35

Metabolism

Question 36

Give examples of metabolic reactions

Answer 36

Building large molecules from various smaller ones- building starch from glucose Breaking large molecules into smaller ones- breaking down carbohydrates Changing one molecule into another- changing sugars like glucose to an amino acid

Question 37

What factors effect enzymes?

Answer 37

Temperature and PH level

Question 38

How does temperature effect an enzyme?

Answer 38

The activity of the enzyme initially increases, until its optimum is reached. When an enzymes optimum is reached, the enzyme becomes denatured and stops working. For human enzymes this is 41 degrees. Their optimum is 37 degrees

Question 39

What is the effect of PH on an enzyme?

Answer 39

Can change he shape of the molecule, resulting in the specific active site being lost, and thus the enzyme no longer being able to act as a catalyst. Each enzyme has an optimal PH, such as lipase working best at an alkaline PH

Question 40

What does mucus protect in the stomach during digestion?

Answer 40

Protects stomach walls from acid and protects them from being digested by the enzymes and acid

Question 41

If someone develops a muscle ulcer, why may they be in pain?

Answer 41

The lining of the stomach is attacked by the acid and protein eating enzymes

Question 42

Give an example of how your body changes PH level?

Answer 42

Bile neutralises the stomach acid so that the small intestine conditions are alkaline

Question 43

How does your body alter the surface area to aid digestion?

Answer 43

The bile also emulsifies the lipids, resulting in a larger surface area of fats for the lipase enzymes to act upon