Biological molecules

Question 1 of 55

1

What is covalent bonding?

Select one of the following:

2 non-metals sharing an eloctron to complete their outer shells
A metal and a non-metal bonding through electrostatic attraction

Explanation

Question 2 of 55

1

In hydrogen bonding, the individual bonds are very strong.

Select one of the following:

True
False

Explanation

Question 3 of 55

1

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The sub-unit of a polysaccharide is a ( monosaccharide, mononucleotide, disaccharide, glucose ). Two of these together form a disaccharide.

Explanation

Question 4 of 55

1

Formation of polypeptides and polysaccharides are ____________ reactions.

Select one of the following:

condensation
hydrolysis
magic

Explanation

Question 5 of 55

1

Fill the blank space to complete the text.

A molar solution is a solution that contains

Explanation

Question 6 of 55

1

❌ join together to make ❌.

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Monomers

Polymers

Nucleotides

polymers

monomers

glucose

Explanation

Question 7 of 55

1

Monosaccharides are...

Select one or more of the following:

Sweet-tasting
Insoluble
Starchy
Soluble
Have the general formula (CH2O)n

Explanation

Question 8 of 55

1

The test for reducing sugars involves adding hydrochloric acid

Select one of the following:

True
False

Explanation

Question 9 of 55

1

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A reducing sugar is a sugar that can reduce another substance by

Explanation

Question 10 of 55

1

To test for reducing and non-reducing sugars we use...

Select one or more of the following:

Tollen's reagent
Benedict's reagent
Starch
Iodine

Explanation

Question 11 of 55

1

What are the results of the Benedict's test for reducing sugars?

Select one or more of the following:

Turns red for a high concentration
Stays blue for no reducing sugars
Turns green for a high concentration
Turns yellow/orange for a medium concentration
Turns purple for a low concentration

Explanation

Question 12 of 55

1

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Glucose plus ( glucose, fructose, lactose ) forms maltose.

Explanation

Question 13 of 55

1

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Glucose plus ( fructose, glucose, galactose ) forms sucrose.

Explanation

Question 14 of 55

1

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Glucose plus ( fructose, galactose, sucrose ) forms lactose.

Explanation

Question 15 of 55

1

Click on the orange point and write the correct answer.

What is this molecule?

Explanation

Question 16 of 55

1

Click on the orange point and write the correct answer.

What is this molecule?

Explanation

Question 17 of 55

1

How does the Benedict's test for non-reducing sugars differ to that of reducing sugars? (tick all appropriate)

Select one or more of the following:

The colour changes are different
You have to add hydrochloric acid after the first round of heating
You add nitrogen sulphide to neutralise the acid
You add sodium hydroxide to neutralise the acid
There is a temperature change after you add the iodine

Explanation

Question 18 of 55

1

Polysaccharides are insoluble

Select one of the following:

True
False

Explanation

Question 19 of 55

1

The test for starch uses ❌. If starch is present it will turn from ❌ to ❌.

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iodine

Tollen's reagent

orange

red

blue

silver

black

purple

Explanation

Question 20 of 55

1

Starch is made of alpha glucose.

Select one of the following:

True
False

Explanation

Question 21 of 55

1

Tick the correct answers.

Select one or more of the following:

Cellulose is found in plants
Cellulose is made of alpha glucose
Glycogen is found in bacteria
Glycogen is made of alpha glucose
Starch is linked by glycosidic bonds
Starch is a straight molecule
Glycogen is short coils with lots of branches
Cellulose is branched
Cellulose has hydrogen bonds that form cross-linkages

Explanation

Question 22 of 55

1

Fill the blank spaces to complete the text.

Lipids are insoluble in but soluble in

Explanation

Question 23 of 55

1

What are some roles of lipids?

Select one or more of the following:

Insulation
Water-absorbant
Protection
Source of energy
Source of nitrogen for plants

Explanation

Question 24 of 55

1

Phospholipids...

Select one of the following:

allow the transfer of lipid-insoluble substances across membranes
contribute to the flexibility of membranes

Explanation

Question 25 of 55

1

Click on the orange point and write the correct answer.

What is this molecule?

Explanation

Question 26 of 55

1

The fatty acids in triglycerides are unsaturated.

Select one of the following:

True
False

Explanation

Question 27 of 55

1

Structure and functions of triglycerides:
The high ratio of carbon-hydrogen bonds to carbon atoms means they are a good ❌.
The low mass to energy ratio means they are good ❌.
The large and insoluble molecules are ❌ and don't affect the ❌ of the cells.
The high ration of hydrogen to oxygen atoms mean they are a good ❌.

Drag and drop to complete the text.

source of energy

storage molecules

good storage molecules

water potential

source of water

Explanation

Question 28 of 55

1

Click on the orange point and write the correct answer.

What is this molecule?

Explanation

Question 29 of 55

1

Phospholipids have...

Select one or more of the following:

A hydrophilic head
A hydrophobic head
A hydrophilic tail
A hydrophobic tail

Explanation

Question 30 of 55

1

Structure and function of phospholipids:
The hydrophilic heads and hydrophobic tails form a ❌ in ❌ environments.
The ❌ heads help hold the surface of the cell-surface membrane.
They can form ❌ with carbohydrates which are important for cell recognition.

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bilayer

aqueous

gaseous

hydrophilic

glycolipids

emulsions

Explanation

Question 31 of 55

1

Select from the dropdown lists to complete the text.

Test for lipids:
1. Add 2cm^3 of your sample and 5cm^3 of ( ethanol, iodine ) to a test tube
2. Shake the tube to dissolve any ( lipids, glucose ) in the sample
3. Add 5cm^3 of ( water, Benedict's reagent ) and shake gently
4. If lipids are present then the solution will turn ( cloudy-white, yellow, blue, black )

Explanation

Question 32 of 55

1

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Amino acids are the basic ( monomer, polymer, sugar ) units for proteins and the polymer is called a ( polynucleotide, polypeptide, polysaccharide ).

Explanation

Question 33 of 55

1

Amino acids provide indirect evidence for...

Select one of the following:

Evolution (the same 40 are in everything)
Meiosis (each is split in two for gametes)
Evolution (the same 20 are in everything)
Mitosis (the same ones are in the daughter cells)

Explanation

Question 34 of 55

1

Label this amino acid structure

Drag an answer into the correct orange point.

R group

Nitrogen

Amino group

Phosphate

Carboxyl group

Carbohydrate

Hydrochloric acid

Hydrogen

Central carbon atom

Central carbon ion

Explanation

Question 35 of 55

1

The process of joining many amino acid monomers together is called polymerisation.

Select one of the following:

True
False

Explanation

Question 36 of 55

1

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The primary structure of a protein is formed by the specific sequence of . The primary structure determines its and therefore function so changing just a single amino acid in the chain could potentially change the way the whole protein works.

Explanation

Question 37 of 55

1

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The ( secondary, tertiary ) structure of a protein is the long polypeptide chain being twisted into a ( 2D, 3D ) shape. This is caused by the ( hydrogen, disulfide ) bonds that form between the H from the ( positive, negative ) NH group of one and the O of another's ( positive, negative ) C=O.

Explanation

Question 38 of 55

1

The tertiary structure of the protein is formed by the secondary structure being further coiled and twisted into a more ❌ and recognisable shape. This shape is maintained by three types of bonds: hydrogen bonds, ❌ bonds and disulfide bridges. The ❌ bonds are numerous but easily broken. The ionic bonds are stronger than the hydrogen bonds however they are easily broken by a change in ❌. The disulfide bridges are the ❌ out of the three.

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complex

hydrogen

pH

temperature

pressure

strongest

weakest

ionic

Explanation

Question 39 of 55

1

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The ( quaternary, tertiary, secondary ) structure is the most complex and consists of many individual polypeptide chain linked in various ways. Some of these molecules have non-protein (( fake, prosthetic, pseudo )) groups associated with them e.g. the ( iron, nitrogen, calcium, magnesium ) containing haem group in haemoglobin.

Explanation

Question 40 of 55

1

What is the test for proteins called?

Select one of the following:

Tollen's
Sterilisation
Biuret
Benedict's

Explanation

Question 41 of 55

1

What are the steps in the test for proteins?

Select one or more of the following:

1. Place your sample and an equal volume of sodium hydroxide in a test tube
1. Place your sample and an equal volume of sodium disulphate in a test tube
!. Place your sample and an equal volume of hydrochloric acid in a test tube
2. Add a few drops of high concentration copper sulphate and mix gently
2. Add a few drops of very dilute copper sulphate and mix gently
3. If it goes red there are peptide bonds and therefore proteins present but stays blue in their absence
3. If it goes purple there are peptide bonds and therefore proteins present but stays blue in their absence
3. If it goes green there are peptide bonds and therefore proteins present but stays blue in their absence

Explanation

Question 42 of 55

1

Fill the blank spaces to complete the text.

Enzymes are globular proteins that act as . They do this by lowering the of a reaction by providing an alternative pathway for the reaction without being themselves.

Explanation

Question 43 of 55

1

The functional region of an enzyme is called the...

Select one of the following:

substrate
active site
complex

Explanation

Question 44 of 55

1

The molecule upon which the enzyme acts is called the...

Select one of the following:

substrate
active site
protein

Explanation

Question 45 of 55

1

Scientists used to use the ❌ model to explain how enzymes work but this is now out-dated. Instead, we use the ❌ model. It suggests that the enzyme's active site changes shape when in close proximity to the ❌ as a result of the ❌ in each molecule. The active site ❌ itself around the substrate to form an ❌ which distorts bonds in the substrate to lower the ❌ energy.

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lock and key

induced-fit

substrate

charges

moulds

enzyme-substrate complex

activation

Explanation

Question 46 of 55

1

For an enzyme to work, it must...

Select one or more of the following:

Come into contact with the substrate
Be diluted in solution
Have the correct orientation so the active site and substrate collide
Have a complementary active site to the substrate
Be at body temperature (37°C)

Explanation

Question 47 of 55

1

The two changes most frequently measured to measure the rate of enzyme-catalysed reactions are...

Select one or more of the following:

Dissapearance of substrate
Amount of gas released
Formation of products
Temperature fluctuation

Explanation

Question 48 of 55

1

Measuring rate of change on a graph involves drawing a tangent to the curve and then working out the change in x divided by the change in y.

Select one of the following:

True
False

Explanation

Question 49 of 55

1

Label this graph of the effects of temperature on enzyme activity

Drag an answer into the correct orange point.

Optimum temperature

Temp too high, enzymes start to denature

As temp increases, kinetic energy does

Temp too low, not enough energy to work

No enzymes left, no activity

Explanation

Question 50 of 55

1

Label this graph of the effects of pH on enzyme activity

Drag an answer into the correct orange point.

Optimum pH

Narrow range

pH too low

pH too high

H+ ion concentration denaturing enzymes

Explanation

Question 51 of 55

1

Label this graph of the effects of enzyme concentration on enzyme activity

Drag an answer into the correct orange point.

Too few enzymes for amount of substrate

All substrate has an active site

Already enough active sites for sub.

Temperature too high

Not enough kinetic energy

Optimum pH

Explanation

Question 52 of 55

1

Label this graph of the effects of substrate concentration on enzyme activity

Drag an answer into the correct orange point.

Not enough sub. to fill all active sites

Max rate, all sub in an active site

All active sites already occupied

Temperature too high

Optimum pH

Not enough kinetic energy

Explanation

Question 53 of 55

1

Fill the blank spaces to complete the text.

inhibitors interfere with the functioning of an enzyme by binding to the active site and getting in the way of the substrate. inhibitors interfere with the functioning of an enzyme by binding to it in a place other than the active site, changing its shape so the active site is no longer to the substrate.

Explanation

Question 54 of 55

1

What is this?

Drag the answer into the correct orange point.

Competitive

Non-competitive

Explanation

Question 55 of 55

1

What is this?

Drag the answer into the correct orange point.

Competitive

Non-competitive

	Created by Georgia Battersby-Hill about 8 years ago

Chapter 1 of AQA AS Biology

Biological molecules

Biological molecules

Question 1 of 55

What is covalent bonding?

Select one of the following:

Explanation

Question 2 of 55

In hydrogen bonding, the individual bonds are very strong.

Select one of the following:

Explanation

Question 3 of 55

Select from the dropdown list to complete the text.

The sub-unit of a polysaccharide is a monosaccharide mononucleotide disaccharide glucose( monosaccharide, mononucleotide, disaccharide, glucose ). Two of these together form a disaccharide.

Explanation

Question 4 of 55

Formation of polypeptides and polysaccharides are ____________ reactions.

Select one of the following:

Explanation

Question 5 of 55

Fill the blank space to complete the text.

A molar solution is a solution that contains

Explanation

Question 6 of 55

❌ join together to make ❌.

Drag and drop to complete the text.

Explanation

Question 7 of 55

Monosaccharides are...

Select one or more of the following:

Explanation

Question 8 of 55

The test for reducing sugars involves adding hydrochloric acid

Select one of the following:

Explanation

Question 9 of 55

Fill the blank space to complete the text.

A reducing sugar is a sugar that can reduce another substance by

Explanation

Question 10 of 55

To test for reducing and non-reducing sugars we use...

Select one or more of the following:

Explanation

Question 11 of 55

What are the results of the Benedict's test for reducing sugars?

Select one or more of the following:

Explanation

Question 12 of 55

Select from the dropdown list to complete the text.

Glucose plus glucose fructose lactose( glucose, fructose, lactose ) forms maltose.

Explanation

Question 13 of 55

Select from the dropdown list to complete the text.

Glucose plus fructose glucose galactose( fructose, glucose, galactose ) forms sucrose.

Explanation

Question 14 of 55

Select from the dropdown list to complete the text.

Glucose plus fructose galactose sucrose( fructose, galactose, sucrose ) forms lactose.

Explanation

Question 15 of 55

Click on the orange point and write the correct answer.

What is this molecule?

Explanation

Question 16 of 55

Click on the orange point and write the correct answer.

What is this molecule?

Explanation

Question 17 of 55

How does the Benedict's test for non-reducing sugars differ to that of reducing sugars? (tick all appropriate)

Select one or more of the following:

Explanation

Question 18 of 55

Polysaccharides are insoluble

Select one of the following:

Explanation

Question 19 of 55

The test for starch uses ❌. If starch is present it will turn from ❌ to ❌.

Drag and drop to complete the text.

Explanation

Question 20 of 55

The sub-unit of a polysaccharide is a ( monosaccharide, mononucleotide, disaccharide, glucose ). Two of these together form a disaccharide.

Glucose plus ( glucose, fructose, lactose ) forms maltose.

Glucose plus ( fructose, glucose, galactose ) forms sucrose.

Glucose plus ( fructose, galactose, sucrose ) forms lactose.

Structure and function of phospholipids:
The hydrophilic heads and hydrophobic tails form a ❌ in ❌ environments.
The ❌ heads help hold the surface of the cell-surface membrane.
They can form ❌ with carbohydrates which are important for cell recognition.

Amino acids are the basic ( monomer, polymer, sugar ) units for proteins and the polymer is called a ( polynucleotide, polypeptide, polysaccharide ).