Carbohydrates Flashcards
Carbohydrates
A macronutrient
Made up of carbon, hydrogen, and oxygen
Divided into starch, sugar and fibre
Main bodily functions: energy for physical activity and bodily functions, fibre to help digestion and flavours food
50% of daily energy
Simple carbs ( sugars)
Absorbed quickly into the body (feel quickly soon after eating)
Monosaccharides
- glucose
- galactose
- fructose
Disaccharides
-sucrose
-lactose
-maltose
Monosaccharides (single molecule)
Glucose - ripe fruit and veg
Fructose - fruits and honey
Galactose - milk from mammals
Disaccharides (two molecules)
Maltose (two glucose joined together ) - barley and malt extract - added to sweets, biscuits and breakfast cereals
Sucrose ( glucose and fructose) - commonly known as as sugar
Lactose ( glucose and galactose ) - milk from mammals and products made from it
Complex carbs
Do not taste sweet. Absorbed slowly in the body ( feel full for longer)
Starch
Pectin
Dextrin
Fibre
Starch
Cereals and grains
Whole meal pasta
Sweet potatoes, parsnips, carrots,beet,acorn squash
Bread and cakes
Pectin
Citrus
Carrots
Fibre
Whole grain cereal
Fruit and veg
Nuts and seeds
Dextrin
Formed when starchy foods are toasted
Glycaemic index
High GI = digested quickly and cause rapid rise
Low GI = digested slowly and cause a gradual rise
Why do we need starchy food in our diet
Slow release energy feel full for longer often give fibre and other vitamins
Chemical composition of carbohydrates
Carbon = C6
Hydrogen = H12
Oxygen = O6
Forming maltose
Condensation reaction occurs
Glycosidic bond is formed
Water is lost
What is the difference between type one and type two diabetes?
Type 1 diabetes causes the level of glucose (sugar) in your blood to become too high. It happens when your body cannot produce a hormone called insulin, which controls blood glucose. You need to take insulin every day to keep your blood glucose levels under control. Managing type 1 diabetes can take time to get used to, but you can still do all the things you enjoy. This guide is here to help.Type 1 diabetes is not linked with age or being overweight – these things are linked with type 2 diabetes.
Type 2 diabetes is a common condition that causes the level of sugar (glucose) in the blood to become too high.
It can cause symptoms like excessive thirst, needing to pee a lot and tiredness. Many people have no symptoms. It increases your risk of getting serious problems with your eyes, feet, heart and nerves.
It’s a long-term condition that can affect your everyday life. You may need to change your diet, take medicines and have regular check-ups.
It’s caused by problems with a chemical in the body (hormone) called insulin. It’s often linked to being overweight or inactive, or having a family history of type 2 diabetes.
What does the pancreas do and why is it relevant to diabetes
Insulin is a hormone made in your pancreas. It helps your body use glucose (sugar) for energy.
In type 1 diabetes your pancreas no longer makes insulin, so you have to inject it to control your blood glucose levels.
Diabetic neuropathy
When diabetes causes damage to your nerves.
Four main types - diabetic peripheral neuropathy
- biabetic sensory neuropathy
Diabetic autonomic neuropathy
Diabetic motor neuropathy
Caused by high blood sugar levels damaging the small blood vessels that supply the nerves in your body - stops essential nutrients reaching the nerves - as a result of this the nerves can become damaged and may disappear.
Cannot be reversed but can be treated with medication and painkillers.
Gestational diabetes
Gestational diabetes is diabetes diagnosed for the first time during pregnancy (gestation). Like other types of diabetes, gestational diabetes affects how cells use sugar (glucose). Gestational diabetes causes high blood sugar that can affect the pregnancy and the baby’s health.
During pregnancy you can help control gestational diabetes by eating healthy foods, exercising and, if necessary, taking medication. Controlling blood sugar can keep you and your baby healthy and prevent a difficult delivery.
If you have gestational diabetes during pregnancy, generally your blood sugar returns to its usual level soon after delivery. But if you’ve had gestational diabetes, you have a higher risk of getting type 2 diabetes. You’ll need to be tested for changes in blood sugar more often.
Biological role of monosaccharides
As an energy source a large amount of energy is stored between the c-h bonds. This is released to form ATP (adenosine triphosphate). ATP is the energy currency of the cell.
As building blocks they are repeated glucose molecules build up; starch and glycogen. Ribose (5C ) forms part RNA . Deoxyribose 5C ) forms part DNA
Disaccharides
Double sugars
Taste sweet
Glucose + glucose = maltose and water
Glucose and fructose = sucrose and water
Glucose and galactose = lactose and water
Complex carbohydrates - polysaccharides
Polymers made up of monosaccharides
Repeated condensation reactions
Normally 1000s of monomers
Polysaccharides are not sugars
Almost entirely made up from glucose molecules
Insoluble
Polysaccharides - starch
Many glucose molecules together in straight chains, stored inside microscopic granules in plants
Glycogen polysaccharide
Animals and humans stored in the liver as energy
Starch
Starch grains are a mixture of amylose and amylopectin
Starch is a polysaccharide
Starch is an insoluble store of glucose
Starch is only found in plant cells
Amylose
Condensation reactions between a glucose (1-4 links)
Forms from 1000s of condensation reactions
Coiled springs are formed
Glycogen
Storage of polysaccharide in animals
Made up of glucose
Stored energy
Has 1-4 links and 1-6 links
Amylopectin
Condensation reactions between a glucose (1-4 links)
Branches of 1-6 links also exist
Coiled springs with a branched structure are formed
Cellulose
The main structural component of cell walls due to its strength which is a result of the many hydrogen bonds found between the parallel chains of microfibrils (70 chains of beta glucose combine to form a microfibril ) ( lots of microfibrils make a fibre)
Has a slow decomposition
Mechanically very strong
It is a polymer of beta glucose
C1-4 links make up this polysaccharide
If C1 and 4 are to react, one glucose molecule needs to flip through 180 degrees.
It is this subtle difference that make cellulose so strong
This structure has H bonds holding it together
