Biology Unit 2: Biological Molecules and Digestion Flashcards
What is Chemical Digestion?
Chemical digestion involves the various chemicals and enzymes that our body
produces, it breaks food down into molecules small enough to absorb
What is Physical Digestion?
Physical digestion involves some kind of movement/crushing/mixing, it mostly happens in the mouth and stomach.
What are the Parts of Digestion?
- Mouth,
- Oesophagus/gullet,
- Stomach,
- Small Intestine,
- Large Intestine,
- Liver,
- Pancreas
Digestion: Mouth
The start of the alimentary canal.
The teeth break up food into smaller pieces (mechanical digestion) so there is more surface area for the various enzymes to digest food into small enough pieces to absorb.
Starch, a complex carbohydrate, starts breaking down here because of an enzyme in the saliva.
Digestion: Oesophagus/gullet
The tube that connects the mouth and the stomach.
Food moves through this tube after it is swallowed and is pushed down by circular muscles.
This process is called peristalsis and is the reason you can swallow even if you are upside down.
Digestion: Stomach
A muscular bag that mixes and breaks down chewed up food (more mechanical digestion).
It contains acid that kills most bacteria and other microbes and an enzyme that breaks down protein into amino acids (chemical digestion).
Digestion: Small Intestine
More enzymes are released at the start of the small intestine and food keeps getting broken down into molecules that can be absorbed (more chemical digestion).
Most of the absorption of nutrient molecules occurs here. It is the longest part of the alimentary canal
Digestion: Large Intestine
Most of the nutrients have been absorbed by the time digested food gets here.
Water is reabsorbed so it can be used in other parts of the body.
The undigested parts (faeces) are pushed through by muscular contractions (peristalsis again) and are eventually removed via the anus.
Digestion: Liver
Is a very large and important organ.
- It helps break down toxins,
- helps control the amount of sugar in our blood,
- and makes bile which helps our body digest and absorb lipids.
Digestion: Pancreas
What is Digestion?
Breaking down of food to make nutrient molecules available to the body
What is an Enzyme?
A protein that acts as a biological catalyst and speeds up chemical reactions
What is a Carbohydrate?
A nutrient molecule that is the main source of energy
What is a Protein?
A Protein is a nutrient molecule that is used for growth and repair
What is a Lipid?
A Lipid is a nutrient molecule that is used for energy, extra energy is also stored in this form in the body
What is Fibre?
Fibre is a material that is not digested and keeps the bowels functioning correctly
What elements do Carbohydrates contain?
- Carbon (C),
- Hydrogen (H)
- Oxygen (O)
What types of Carbohydrates are there?
They can be
- simple like glucose and other sugars, or
- complex like starch.
How are Complex Carbohydrates digested?
When complex carbohydrates are digested they are broken down into sugars that our bodies can use for respiration.
What do our Bodies use energy For?
Our Body uses Energy for Life Processes like growth, movement, and keeping us warm
What are Some foods high in Carbohydrates?
Some Foods high in Carbohydrates: Bread , Pasta , Rice, Corn , Potatoes, Fruit
What are Proteins?
Proteins are the main source of new building material
How are Proteins Digested?
Proteins are Broken Down and made into New Proteins in our bodies.
What are Proteins Made up of?
Proteins are made up from molecules called Amino Acids, these amino acids are used to make all of the different proteins in our bodies, like muscle protein.
What Elements do Proteins contain?
All the Elements in Carbohydrates
- Carbon (C),
- Hydrogen (H)
- Oxygen (O)
AND:
- Nitrogen (N)
- Sulphur (S)
What is Protein Used for in the Body?
Protein is used for Growth and Repair. People that are more active, or still growing, usually need more protein.
What are foods High in Protein?
Foods high in protein: Eggs, Meat , Nuts, Avocado, Fish, Cheese
What are Lipids?
Lipid is the biological name for Fats and Oils
What are Lipids ( Fats and Oils ) a Good Source of?
- Lipids are a Major source of Energy
- Lipids contain even more Energy than Carbohydrates.
What Elements are Lipids( Fats and Oils ) Made up of?
Lipids are Made up of the same elements as Carbohydrates
- Carbon (C),
- Hydrogen (H)
- Oxygen (O)
BUT: They have a Different chemical Structure.
What is the Difference Between Fats and Oils?
The Main Difference between Fats and Oils is
- Fats are usually Solid at Room Temperature (about 20°C)
- Oils are usually Liquids at Room Temperature.
What are Foods High in Lipids
( Fats and Oils )
Foods High in Lipids:
- Nuts,
- Vegetable Oil ,
- Oily Fish,
- Some Meats,
- Avocado,
- Cheese
What are Foods with Good Fats?
Some Foods high in Good Fats?
Avocados, Eggs, Coconut Oil, Raw Nuts, Olive Oil, salmon, Flaxseed, Leafy Green Veg, Organic Butter, Organic Nut Oils
What are Some Foods High in Bad Fats?
Some Foods High in Bad Fats are:
Margarine, French Fries, Doughnuts, cookies, Pastries, Crackers, Processed Meats, Canola Oil, Hydrogenated Oils
What is Vitamin A Good For?
Vitamin A is Important for:
Healthy Eye Sight (including night vision), Growth, and Fighting Infections
What are some Foods High in Vitamin A?
Foods High in vitamin A are:
Dairy products, Leafy Green Vegetables, Carrots, Kumara
What is Vitamin C good for?
Vitamin C is Important for: Important for:
Growth, helps absorb other Minerals, Fighting Infections
What are Some Foods High in Vitamin C?
Some Foods High in Vitamin C: most Fruits and Vegetables have some, Capsicum, Kiwi Fruit and Citrus Fruit have higher amounts.
What is Vitamin D Good for?
Vitamin D is Important for :
Very Important for bone health as it helps the body Absorb Calcium
What are some Foods high in Vitamin D?
Foods high in Vitamin D: Eggs, Oily Fish, Dairy Products. Our body is able to make its own vitamin D by using sunlight.
How much of the Body is Made up of Water?
50%-60% of the Body is Made up of Water
Where is the Water in Our Bodies?
Most of the Cytoplasm in our Body’s Cells is made up of Water and Most of our Body’s Fluids are Made up of Water
How is Fibre Digested?
Fibre is NOT Digested in the body but Helps Your Digestive System work Properly
How does Fibre Help Your Digestion?
Fibre Helps Your Digestion by Keeping things Moving So you don’t get Constipated
What are Foods High in Fibre?
Foods High in Fibre:
- Whole grain pasta
- Whole grain bread (brown bread with seeds)
- Vegetables
- Nuts
- Seeds
- Brown rice
What is the The Alimentary Canal?
The function of the alimentary canal is to break down foods into a form that can be absorbed and used by the body. It is basically a long tube that starts at the mouth and ends at the anus. Each part of the alimentary canal has a specific role in digesting and absorbing the different nutrient molecules in our food.
What do Enzymes do in the Body?
Enzymes are biological catalysts, they are proteins that our bodies make that speed up chemical reactions without being used up in the reaction.
How do Enzymes Work with Molecules?
Enzymes work like a lock and key, the enzyme is a particular shape and only works with one type of biological molecule.
