IB Biology Topic 2

What is the primary function of lipids?

long term energy storage

What are nucleic acids?

Genetic material of all cells and determines the inherited features of an organism

What is nucleic acids monomer?

nucleotide

What is nucleic acids polymer?

DNA and RNA

What is a proteins monomer?

amino acids

What is a proteins polymer?

polypeptide

What is lipids polymer?

triglyceride

What is a disaccharide?

two monosaccharides joined together

What structure do monosaccharides form?

Ring structures

Do lipids have monomers?

They do not have a common reoccurring monomer

What are unsaturated fats?

Long hydrocarbon chains that have single bonds and are good fats

What are saturated fats?

Long hydrocarbon chains that have at least one double bond and are bad fats

What carbohydrate is liver tissue made of

Glycogen

What carbohydrates are leaf tissues made of?

Cellulose and starch

What are the simple lipids

triglycerides and waxes

What are the compound lipids?

phospholipids, glycolipids, lipoproteins

What are derived lipids?

Steroids and carotenoids

What bonds join amino acids together?

peptide bonds

What is metabolism?

the chemical processes that occur within a living organism in order to maintain life.

What are the 2 functions of metabolism?

Source of energy for cellular processes, they enable the synthesis and assimilation of new materials for use within the cell

What is an anabolic reaction?

Builds larger molecules from smaller molecules and usually occur by a condensation reaction

What is a catabolic reaction?

Breaks down larger molecules into smaller molecules typically involves oxidation reactions

Why does water have a permanent dipole?

Because the oxygen has higher electronegativity it pulls the electrons closer so it has a partial negative charge and hydrogen has a partial negative

What are the 4 properties of water?

cohesion, adhesion, surface tension and solvent properties

Why does water have a high specific heat capacity?

The hydrogen bonds between water molecules can absorb a lot of energy so it takes a lot of energy to heat water up

What is cohesion?

Attraction between molecules of the same substance

What is adhesion?

An attraction between molecules of different substances

Why does water have a high surface tension?

hydrogen bonding allows the water to resist low levels of external force

What joins monosaccharides together?

glycosidic bonds

What is the main function of monosaccharides

energy source

What are 3 examples of monosaccharides?

glucose, fructose, galactose

What is the main function of disaccharides

transport form

What are 3 examples of disaccharides?

sucrose, maltose, lactose

What is the main function of polysaccharides?

storage form

What are 3 examples of polysaccharides

starch, glycogen, cellulose

What type of glucose forms cellulose

beta glucose

What type of glucose forms starch

alpha glucose

What are the 4 main classes of Carbon compounds?

carbohydrates, lipids, proteins, nucleic acids

What is the primary function of carbohydrates?

provide energy

What is the primary function of proteins?

build and repair body tissues

What is carbohydrates monomer?

monosaccharide

What is carbohydrates polymer?

polysaccharide

What are the 2 types of starch

amylose and amylopectin

What are the differences between amylase and amylopectin

Amylase is linear amylopectin is branched
Amylase is harder to digest and less soluble
Amylopectin takes up more space

What type of glucose is glycogen made up of

alpha glucose

Which polysaccharides of glucose have 1-4 glycosidic bonds?

Cellulose, amylose, amylopectin and glycogen

Which polysaccharides of glucose have 1-6 glycosidic bonds?

Amylopectin and glycogen

What are the properties of saturated fats

Contain no double bonds in their hydrocarbon tail

Solid

General public considers bad for your health.

What are the properties of unsaturated fats

liquid at room temperature,

plant origin

have double carbon bond

What is a cis unsaturated fatty acid?

The hydrogen atoms attached to the carbon double bond are on the same side

What is a trans unsaturated fatty acid?

The hydrogen atoms attached to the carbon double bond are on different sides

What are the properties of trans unsaturated fats

Produced industrially by hydrogenation

Linear

Solid

What is the function of triglycerides

long term energy storage

How are triglycerides formed?

3 condensation reactions between glycerol and 3 fatty acids

What kind of bond joins a triglyceride

Ester bond

What types of fats raise blood cholesterol levels

Saturated fats and trans fats

What types of fats lower blood cholesterol levels

Cis unsaturated fats

What are low density lipoproteins?

Transports cholesterol from liver to body
Increased by saturated fats and trans fats which raise blood cholesterol

What are high density lipoproteins?

Scavenge excess cholesterol and Carrie's it back to the liver for disposal
Levels are decreased by trans fats
Levels are increased by cis unsaturated fats lowering blood cholesterol

What are health risks of high cholesterol

Leads to hardening and narrowing of arteries (atherosclerosis)

When there are high levels of LDL in the bloodstream, the LDL particles will form deposits in the walls of the arteries

The accumulation of fat within the arterial walls lead to the development of plaques which restrict blood flow

If coronary arteries become blocked, coronary heart disease (CHD) will result - this includes heart attacks and strokes

Why is energy stored as carbohydrates

Mono and disaccharides are water soluble
Carbohydrates are easier to digest
But they store less energy per gram

Why is energy stored as lipids

Triglycerides can store more energy per gram
However they are insoluble in water and not easily digested

How do you calculate BMI?

weight in kg/ (height in meters)^2

What is the basic structure of an amino acid?

An amine group, a carboxyl group, a functional R-group and a hydrogen atom bonded to a centeral carbon

Why do amino acids differ in their properties?

differing side chains, called R groups

How are amino acids linked together?

peptide bonds in a condensation reaction

What is the primary structure of a protein?

sequence of amino acids

What is the secondary structure of a protein?

alpha helix or beta pleated sheet

What bonds occur in secondary protein structures

Hydrogen bonds

What is the tertiary structure of a protein?

3D structure including bending

What is the quaternary structure of a protein?

two or more polypeptide chains joined

What is an example of a quaternary structure protein

hemoglobin

What are immobilised enzymes?

Enzymes that are attached to an insoluble material so they can't become mixed with the products

What are some industrial uses of immobilised enzymes

Paper production, food (dairy) production, biofuel production

What are examples of structural proteins

Collagen - Component of connective tissue in animals

Spider silk- Spun and used by spiders to make webs (stronger by weight than steel)

What are some examples of hormonal proteins

Insulin: Protein produced by the pancreas and triggers a reduction in blood glucose levels

What are some examples of immunity proteins

Immunoglobulins: Antibodies produced by plasma cells that are capable of targeting specific antigens

What are some examples of sensation proteins

Rhodopsin: A pigment in the photoreceptor cells of the retina that is responsible for the detection of light

What are some examples of proteins as enzymes

Rubisco: An enzyme involved in the light independent stage of photosynthesis

What can travel in the plasma of the bloodstream

Water soluble substances will usually be able to travel freely in the blood plasma, whereas water insoluble substances cannot

What are the water soluble components of blood plasma

Sodium chloride (NaCl) , components (Na⁺ and Cl^–) may be freely transported within the blood

Glucose contains many hydroxyl groups (–OH) which may associate with water and thus can freely travel within the blood

Amino acids will be transported in the blood in an ionised state (either the amine and/or carboxyl groups may be charged)

What are the water insoluble components of blood plasma

Lipids (fats and cholesterol) are non-polar and hydrophobic and hence will not dissolve in water

They form complexes with proteins (lipoproteins) in order to move through the bloodstream

Hydrophilic portions of proteins, cholesterol and phospholipids will face outwards and shield internal hydrophobic components