Chapter 3 - Food Flashcards
What is nutrition
The way in which an organism obtains and used food
3 reasons for nutrition
Source of energy
Makes chemicals for metabolic reactions
Growth and repair if structures in the organism
What is metabolism
The sum of all chemical reaction
Name the two types of metabolic reactions
Anabolic reaction
Catabolic reaction
What is an anabolic reaction
Convert smaller molecules into larger ones
It requires enzymes and uses energy
An example of an anabolic reaction
Photosynthesis
What is a catabolic reaction
Complex (larger) molecule broken down into a simpler (smaller) molecule
It requires enzymes and uses energy
An example of a catabolic reaction
Respiration
Name the six common elements in food
C = carbon H = hydrogen O = oxygen N = nitrogen O = phosphorus S = sulfur
Name the 5 salts dissolved in food
Na = sodium Mg = magnesium Cl = chlorine K = potassium Ca = Calcium
Name the 3 trace elements in food
Fe = Iron Cu = copper Zn = zinc
What is a bio molecule
Chemicals that are made inside a living thing
Contains carbon
Name the four types of bio chemicals
Carbohydrate
Lipids (fats,oils)
Proteins
Vitamins
What elements are found in carbohydrates and what is the ratio
C = carbon
H = hydrogen
O = oxygen
Cx (H2O)y
Describe the structure of a carbohydrate
Monosaccharides- one sugar unit - glucose (sweet + soluble)
Disaccharides - two sugar units - sucrose (sweet + soluble)
Polysaccharides - many sugar units - starch (not sweet + insoluble)
Name 4 sources of carbohydrate
Bread
Potatoes
Rice
Pasta
What is the structural role of a carbohydrate
Cellulose - used for plant cell wall
Chitin - used in cell walls of fungi and insects exoskeleton
What is the metabolic role of carbohydrate
Respiration - breaking down glucose for a release of energy (catabolic) (short term)
What elements are found in lipids
C = carbon H = hydrogen O = oxygen
What is the difference between lipids and fat
Lipids are liquid at room temperature (oil)
Fat is solid at room temperature (butter)
What is the structure of lipids
Triglycerides - glycerol and 3 fatty acids
Phospholipids - glycerol, 2 fatty acids and phosphate group
Name 4 sources of lipids
Oil
Butter
Cream
Lard
What is the structural role of lipids
For storage
Gives heat insulation and protection to organs
What is the metabolic role of lipids
Respiration - (long term) release of energy
What are the elements in proteins
C = carbon H = hydrogen O = oxygen N = nitrogen Sometimes - P = phosphorus S = sulfur
What is the structural of proteins
Made of amino acids
Protein is more than 200 amino acids
Fibrous - strong, no folding e.g. keratin in nails and hair
Globular - folding, rounded e.g. myosin (muscles)
What is a peptide
less than 20 amino acids
What is a polypeptides
More than 20 peptides
What is protein
More than 200 amino acids
Name 4 sources of proteins
Meat
Eggs
Nuts
Beans
What is the structural role of protein
Keratin in skin, hair, nails
Myosin in muscles
What is the metabolic role of protein
Used as enzymes
Antibiotics
Some hormones
(Catabolic)
What do hormones do
Regulate body reactions
Name 2 vitamins studied
Vitamin C
Vitamin D
What elements are present in vitamins
They are carbon based
Not made by the body
What is the structure of vitamin c
Ascorbic acid (water soluble)
What is the structure of vitamin D
Calciferol (fat soluble)
What are sources of vitamin D
Dairy products
Egg yolk
Fish liver oils
Sunlight is needed
What are sources of vitamin C
Citrus fruits
Green vegetables
What is the cellular structure of vitamin c
Builds connective tissue e.g. skin
What is the structural role of vitamin D
Absorbs calcium from food e.g. needed for teeth and bones
What deficiency does lack of vitamin c cause
Scurvy - bleeding gums
What deficiency does lack of vitamin d cause
In a child rickets
In adults osteomalica
What three ways are minerals used
Form part of rigid body structure
Form soft tissues in the body
Function in cellular and body fluid
What are the 2 minerals in plants, where do they get them from and what are they used for
Calcium - salt absorbed from soil, helps bind cell walls together
Magnesium - salt absorbed from soil, part of structure of chlorophyll
Name 2 minerals in animal, where do they get them and what are they used for
Calcium - milk, cheese, hard drinking water, forms bones and teeth
Iron - liver, meat, green vegetables, part of structure of haemoglobin
What does water account for
99% of all molecules in the body
60%-65% of body mass
90% of mass of plants
What are the three main reasons for water
Where all metabolic reaction takes place
Basis for transport
Environment in which many organisms live
name 5 examples of reasons for water and describe
Component of cytoplasm and body fluids - most common chemical in cells (cytoplasm)
Good solvent - dissolves a wide range of molecules (allows chemical reactions in cytoplasm and organelles) ( transports some of these molecules)
Participated in chemical reactions - Photosynthesis + respiration
Movement through membranes - osmosis (cells become swollen or shriveled)
Good absorber of heat - slow to heat up and slow to cool down (oceans have relatively stable temperatures) (organisms can keep temperatures stable)
What does ECF stand for
Extra Cellular body fluid
