2.2 - Biological molecules

studied byStudied by 1 Person
0.0(0)
Get a hint
hint

A student mixed an unknown substance with water and ethanol. A white suspension formed in the tube. What is present? [1]

1/157

Studying Progress

New cards
157
Still learning
0
Almost done
0
Mastered
0
157 Terms
New cards

A student mixed an unknown substance with water and ethanol. A white suspension formed in the tube. What is present? [1]

Lipids are present

New cards
New cards

Buoyancy of triglycerides

Fat is less dense than water, it is used by aquatic animals to help them stay aflot

New cards
New cards

Chloroplast

It is a steroid alcohol - a type of lipid which is not made from glycerol or fatty acids

New cards
New cards

Cohesion in water

water molecules stick together as a result of hydrogen bonding

New cards
New cards

Density of water

It provides an ideal habitat for living things.

New cards
New cards

Describe amylose

It contains alpha glucose, with 1-4 glycosidic bonds and all monomers are in the same orientation.

New cards
New cards

Describe and explain how the structure and properties of different carbohydrate and lipid molecules suit them to their role as energy storage molecules in plants and animals. [6]

q19

New cards
New cards

Describe how an enzyme, such as pepsin, breaks down a substrate.

substrate shape is complementary to active site, it then fits into the active site. It is an induced fit and forms enzyme-substrate complex, then products leaves

New cards
New cards

Describe how to do the emulsion test for lipids and how a positive result would be identified.

mix with / add , ethanol / alcohol , and water ; (goes) cloudy

New cards
New cards

Describe the formation of a hydrogen bond between two molecules of water and explain why water can form these bonds.

between O and H between electropositive H and electronegative O as it is polar

New cards
New cards

Describe the formation of a hydrogen bond between two molecules of water and explain why water can form these bonds. [3]

1.between O and H (of adjacent molecules); 2. between, electropositive / δ+ / delta+ (H), and, electronegative / δ- / delta- (O); 3.water molecule, is polar / has charge separation;

New cards
New cards

Describe the primary level of protein structure.

peptide bonds and the sequence of amino acids

New cards
New cards

Describe the process of adhesion [2]

attraction of water molecules to the impermeable walls of xylem tissue

New cards
New cards

Describe the role of cholesterol in cell surface membranes in the human body

Cholesterol binds to phospholipid fatty-acid tails/phosphate heads, increasing the packing of the membrane, therefore reducing the fluidity of the membrane.

New cards
New cards

Disulfide links

The strongest of attractions, this is a covalent chemical bond that crosslinks different protein strands together, giving someone's hair the natural tendency to be straight or curly

New cards
New cards

Draw a condensation reaction

New cards
New cards

Draw a pentose sugar

New cards
New cards

Draw a saturated fatty acid

New cards
New cards

Draw a unsaturated fatty acid

New cards
New cards

Draw an alpha glucose

New cards
New cards

Draw an beta glucose

New cards
New cards

Draw glycerol

Draw glycerol

New cards
New cards

Draw primary structure of a protein

New cards
New cards

Draw the formation of a triglyceride

New cards
New cards

Draw the general structure of an amino acid molecule in the space below.

New cards
New cards

Draw the molecular structure of an amino acid

New cards
New cards

They can be broken down in respiration to release energy and generate ATP.

Energy source of triglycerides

New cards
New cards

Its insoluble in water, they can be stored without affecting the water potential of the cell.

Energy store of triglycerides

New cards
New cards

hydrophilic head and hydrophobic tails (1) hydrophobic part / tails, repelled / AW, by water head / hydrophilic part, forms H bonds with water

Explain how the structure of phospholipids allows them to form the bilayer of a plasma membrane.

New cards
New cards

idea that the glycogen deposited is, in long chains / not branched, so not compact (which damages liver cells);

Glycogen storage disease type IV occurs when the liver is unable to catalyse the addition of branches of glucose molecules. People with this disease may develop liver damage over time. Suggest why this disease may result in liver damage.

New cards
New cards

Water requires a lot of energy to change temperature

High specific heat capacity

New cards
New cards

The phosphate group has a negative charge making polar, however the fatty acid tails are non-polar and are repelled by water.

How do phospholipids behave in water?

New cards
New cards

Hydrolyse the ester bonds and then both glycerol and the fatty acids can be broken down completely to carbon dioxide and water. Respiration of a lipid produces more water than respiration of a sugar

How do triglycerides break down for respiration?

New cards
New cards

2

How many hydrogen atoms for one oxygen atom in a carbohydrate?

New cards
New cards

Very weak bonds; occurs when a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule

Hydrogen bonds

New cards
New cards

water loving

Hydrophilic

New cards
New cards

Water fearing

Hydrophobic

New cards
New cards

Adipose tissue is a storage location for lipids in whales acting as a heat insulator.

Insulation of triglycerides

New cards
New cards

Formed when one or more electrons are transferred from one atom to another

Ionic bonds

New cards
New cards

starch AND glycogen

Name the carbohydrate molecules used to store energy in plants and animals

New cards
New cards

peptide bond

Name the covalent bond between two adjacent amino acids in a chain of amino acids.

New cards
New cards

hydrolysis; water is added

Name the type of reaction involved in breaking this bond and describe what happens in this reaction.

New cards
New cards

subunits quaternary

Polypeptides known as alpha (α) and beta (β) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ form part of the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ structure of haemoglobin.

New cards
New cards

Humans have fat around delicate organs to act as a shock absorber.

Protection of triglycerides

New cards
New cards

primary structure

State the name given to the sequence of amino acids in a protein molecule.

New cards
New cards
  1. 1-4 glycosidic

  2. maltose

State the precise name of the covalent bond that forms between the two glucose molecules and the name of the disaccharide that is formed. [2]

New cards
New cards

(enzymes are) globular, proteins / polypeptide; hydrophilic / water soluble, (R-)groups on outside (of enzyme);

State why the structure of enzyme molecules allows them to be detected in solution using the biuret test.

New cards
New cards

facilitated diffusion (1) conversion of ornithine into citrulline creates concentration gradients

Suggest the method by which these molecules move into and out of the organelle during the cycle. Give reasons for your choice

New cards
New cards

protein/polpeptide

Sulfur atoms are required for the synthesis of which type of biological molecule? [1]

New cards
New cards

The water molecules at the surface ar ehydrogen bonded to the molecules un

Surface tension in water

New cards
New cards

secondary

The _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ structure of collagen is described as a left-handed helix because of the direction in which the polypeptide twists.

New cards
New cards

The phospholipid bilayer

A double layer of phospholipids that makes up plasma and organelle membranes.

New cards
New cards

The secondary structure of a protein is determined by the arrangement of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ bonds, which stabilise the structure.

hydrogen

New cards
New cards

The secondary structure of a protein may contain many regions folded in zig-zag patterns known as .....

beta- pleated sheet

New cards
New cards

Water as a reactant

Foods are broken down into their building blocks by adding water. This would be an example of which characteristic of water?

New cards
New cards

Water as a solvent

many substances dissolve well in water because their polar molecules bond easily with other polar molecules

New cards
New cards

What are amino acids?

building blocks of proteins

New cards
New cards

What are disaccharides?

double sugars

New cards
New cards

What are ester bonds?

bonds between fatty acids and glycerol

New cards
New cards

What are fatty acids?

carboxylic acids, typically with a single long chain, although they can be branched

New cards
New cards

What are lipids?

A group of substances that are soluble in alcohol rather than water.

New cards
New cards

What are polysaccharides made out of?

Hundreds or thousands of monosaccharide monomers bonded together

New cards
New cards

What are polysaccharides?

polymers of monosaccharides

New cards
New cards

What are the 3 main groups of carbohydrates?

monosaccharides, disaccharides, polysaccharides

New cards
New cards

What are the 3 most important lipids?

triglycerides, phospholipids, steroids

New cards
New cards

What are the different types of disaccharides?

maltose, sucrose, lactose and cellobiose

New cards
New cards

What are the different types of polysaccharide?

Amylose, amylopcetin and glycogen

New cards
New cards

What are the features of monosaccharides?

Sweet, soluble in water and crystalline. They are easily oxidised and so are called reducing sugars

New cards
New cards

What are the features of phospholipids?

The phosphate head is hydrophilic and the fatty acid tail as hydrophobic

New cards
New cards

What are the functions of triglycerides?

Energy source Energy store Insulation Buoyancy Protection

New cards
New cards

What are the properties of water?

cohesion and surface tension , high specific heat, high heat of vaporization, density, reactant and solvent

New cards
New cards

What charge is hydrogen?

positive

New cards
New cards

What charge is oxygen?

negative

New cards
New cards

What do carbohydrates contain?

carbon, hydrogen, oxygen

New cards
New cards

What do carbohydrates do?

They act as a source of energy, as structural units and are also part of other molecules such as nucleic acids

New cards
New cards

What do lipids contain?

carbon, hydrogen, oxygen

New cards
New cards

What do nucleic acids contain?

carbon, hydrogen, oxygen, nitrogen, phosphorus

New cards
New cards

What do phospholipids look like in the presence of detergent?

B

New cards
New cards

What do proteins contain?

carbon, hydrogen, oxygen, nitrogen, sulfur

New cards
New cards

What do proteins do?

Help build and maintain cells.

New cards
New cards

What does amylopectin contain?

it contains 1-4 and 1-6 glycosidic bonds between α-glucose monomers

New cards
New cards

What does it mean if a fatty acid is saturated?

every C atom is bonded to at least two H atoms, max number of H

New cards
New cards

What does it mean if a fatty acid is unsaturated?

there is at least one double bond between successive C atoms (liquid at room temp)

New cards
New cards

What does polar mean?

unequal sharing of electrons

New cards