B3-organisation and the digestive system

Question 1

what is the pathway of digestion

Answer 1

mouth–>osophegus–>stomach–>pancreas, liver, gall bladder–>small intestine–>large intestine–> rectum –> anus

Question 2

what is digestion

Answer 2

Digestion = the breakdown of large, insoluble molecules, to smaller soluble molecules

Question 3

why must nutrients be soluble

Answer 3

Nutrients must be soluble so that they can dissolve into our blood plasma and be transported to the cells where they are needed

Question 4

what do glands produce

Answer 4

Glands like pancreas and salivary glands release enzymes to break down food

Question 5

what absorbs nutrients

Answer 5

Nutrients are absorbed into the blood from the small intestine

Question 6

what absorbs water

Answer 6

Water is absorbed from the large intestine - once all the water has been absorbed into the blood, what’s left is faeces

Question 7

how does food move in the intestines

Answer 7

Food moves through the intestines by the muscles squeezing –> peristalsis

Question 8

what are our main food groups

Answer 8

Our main food groups are carbohydrates, proteins and lipids

Question 9

what are polymers

Answer 9

These are all polymers - they are made up of smaller molecules to form one big molecule

Question 10

what can our main food groups be broken down into

Answer 10

carbohydrates–> glucose
protein–> amino acids
lipids–>glycerol and fatty acids

Question 11

what is glucose in terms of molecules

Answer 11

Glucose is a single sugar molecule

Question 12

what are complex sugars and some examples

Answer 12

Complex carbohydrates like starch, cellulose are made up of simple sugar units bonded together

Question 13

what are lipids important in

Answer 13

Lipids are important in your cell membranes, hormones and nerve cells

Question 14

what are lipids

Answer 14

Lipids are fats and oils

Question 15

why cant lipids dissolve in water

Answer 15

All lipids are insoluble in water

Question 16

why are proteins important

Answer 16

15-20% of your body is protein. It is used to build your muscles, and enzymes, hormones, antibodies, antigens are all proteins

Question 17

what are the appearance of protein and why are these shapes important

Answer 17

The long chains of amino acids are folded up into specific 3D shapes –> the shapes of proteins are very important because they allow them to carry out their function as best as possible

Question 17

in terms of protein enzymes; what are bonds, what are they sensitive to and what happens when they are broken

Answer 17

Once folded, proteins are kept in that specific shape by bonds

These bonds are very sensitive to temperature and pH

If these bonds are broken, the proteins become ‘denatured’ and lose their shape

Question 18

whats the definition of enzyme

Answer 18

Enzyme = a biological catalyst - it increases the rate of reaction (speeds up) of chemical reactions in the body

Question 18

what does catalyst mean

Answer 18

Catalysts = something that speeds up a chemical reaction without being used up - they can be used over and over again

Question 19

why are enzymes special

Answer 19

Enzymes have a SPECIFIC shape, that allows them to bind to only ONE substrate

Question 19

what are enzymes

Answer 19

Enzymes’ are large protein molecules and their shape is really important to their function

Question 20

what is the lock and the key in the lock and key model

Question 21

FUN FACT: Enzymes can join together small molecules as well as break large ones up

Answer 21

FUN FACT: Enzymes can join together small molecules as well as break large ones up

Question 22

What do enzymes control

Answer 22

Enzymes control metabolism