Biochemistry 1st year Topic 3 Flashcards
What is an organic molecule?
A molecule containing carbon and hydrogen
What is an inorganic molecule?
A molecule without carbon and hydrogen
What are the 3 most common elements that make up biological structures?
Carbon
Hydrogen
Oxygen
However the body needs other elements to build up proteins and other structures. Mention a few.
Calcium,potassium,phosphorus,nitrogen,sulfur,iron etc
What are the 3 most common nutrients?
Carbohydrates,proteins and lipids
What are carbohydates made up of and how can we divide them?
carbon
hydrogen
oxygen
monosaccharides
disaccharides
polysaccharides
Describe the structure of monosaccharides, disaccharides and polysaccharides.
Monosaccharides: only contain 1 carbon ring in their atoms. (simple sugar)
Disaccharides: contain 2 carbon rings in their atoms (2 monosaccharides bonded together)
Polysaccharides: many monosaccharides bonded together (usually glucose)
Give examples of monosaccharides, disaccharides and polysaccharides and where we can find them.
Monosaccharides: glucose,fructose and galactose
Disaccharides: lactose,maltose and sucrose
Polysaccharides: glycogen,cellulose and starch
Monosaccharides: main source of energy for cells
Disaccharides: sucrose: the most simple table sugar + lactose is foud in milk and dairy products
Polysaccharides: cellulose is found in the cell walls of plant cells
glycogen is found in the cytoplasm of animal cells (energy storage)
starch is found in the cytoplasm of plant cells (energy storage)
What are lipids made up of and say if they are soluble or insoluble?
carbon,hydrogen and oxygen
insoluble (non-polar)
What is the monomer of lipids?
Explain its structure and draw a diagram.
Triglyceride: 1 glycerol molecule bonded to 3 fatty acid molecules.
What do we call many triglycerides joined together?
wax
Mention some examples of lipids.
oil,fat,phospholipids,cholesterol.
What are lipids mainly used for?
Insulation
energy
protection
storage
Lipids are usually found under the skin
What are proteins made up of and mention its monomer?
carbon,hydrogen,oxygen,nitrogen and sulfur.
amino acids
Mention some examples of protein.
keratin (makes up hair)
haemoglobin (found in red blood cells)
What is the smallest unit of an element?
atom
What is a molecule?
It is a group of atoms bonded together
What is a compound?
It is a group of different atoms bonded together
What is an atom made up of?
Nucleus
protons (positively charged)
neutrons (do not have no overall charge)
electrons (negatively charged)
An atom has the same number of neutrons as well as the same number of PROTONS
What is an ion?
An atom which is losing or gaining an electron
What happens to the atom if it loses or gains an electron?
If it loses an electron it becomes more positive,if it is gaining an electron its becoming more negative.
What is the difference between an ionic and a covalent bond?
An ionic bond: the attraction between oppositely charged ions forms an ionic bond
A covalent bond: the attraction between the sharing of electrons from the same atoms
Water is made up of 2 hydrogen atoms bonded to one oxygen atom forming hydrogen bonds that give water unique properties.
Mention some chemical properties of water
1) Water is a universal solvent ex: sugar or salt. (important chemical reactions taking place in animal or plant cells. This means it can dissolve a lot of substances in it especially polar substances.
2) High specific heat capacity: it can absorb heat without changing its temperature quickly
3) cohesion and adhesion forces: water molecules stick and attach ex: this allows water to be pulled up from the roots up into the leaves + allows insects to “walk on water due to the surface tension. (allows water to resist external force)
Cohesion: when water molecules stick to each other
Adhesion:when water molecules attach to other substances
4)Material carrier: carries sperm to the ova + 50% of the blood contains water to transfer substances
5) Lubricant: mucous is secreted externally in some animals like snails helping them to move
6)Has a metabolic role: chemical reactions need water to occur and are important in hydrolysis (break-down of large molecules using water)
7) Supportive functions such as : in the hydroskeleton of some organisms and it aids in the plants turgor pressure
What are simple and complex carbohydrates?
Simple: they can exist as simple sugars like glucose or fructose
Complex:more complex like starch and cellulose
Mention some foods which contain carbs
pasta,bread,rice and potatoes
The number of carbon atoms in monosaccharides can vary in 3 types. What are these called?
Pentoses 5
hexoses 6
septoses 7
What is the chemical formula of glucose?
C6H12O6
Draw the structure of a glucose molecule
True or false. Carbohydrates are broken down more rapidly than other nutrients
True
What is excess glucose converted to?
Glycogen and excess glycogen is converted to fat for storage
What are disaccharides made up of and what type of bond do we have between ?
Disaccharides are made up of 2 monosaccharides joined togther by a glycosidic linkage bond.
How are lactose,sucrose and maltose formed?
lactose:glucose + galactose
sucrose:glucose + fructose
maltose: glucose + glucose
Where is sucrose mainly found?
In plants and it is transported thorugh the phloem tissue+
sugar we normally buy in shops and found in sugar cane
What are hydrolysis and condensation reactions? + give an example
Hydrolysis is when: water is added to separate molecules
Condensation: water is removed to join molecules
Condensation :
glucose + glucose = maltose + WATER
Hydrolysis:
Maltose + WATER = glucose + glucose
Polysaccharides are complex carbohydrates.
Describe their structure.
Polysaccharides are made up of repeated monosaccharides joined together by glycosidic linkages. (usually glucose)
True or false
Polysaccharides are soluble.
False
INSOLUBLE
True or false
Polysaccharides can be branched or unbranched
True
Where is glycogen stored in the body?
The liver and the muscles
Mention some examples of lipids and ther consistency in room temperature
fats:solids at room temperature and oils are liquids at room temperature