Topic 1

Question 1

What are the three types of carbohydrates?

Answer 1

Monosaccharides, disaccharides, polysaccharides

Monosaccharides are single sugar units, disaccharides are composed of two monosaccharides, and polysaccharides consist of long chains of monosaccharides.

Question 2

What is the structure of hexose glucose?

Answer 2

Alpha and beta forms

Hexose glucose can exist in two anomeric forms: alpha (α) and beta (β), which differ in the orientation of the hydroxyl group on the first carbon.

Question 3

How do monosaccharides join to form disaccharides?

Answer 3

Through condensation reactions forming glycosidic bonds

Monosaccharides like glucose, fructose, and galactose can combine to form disaccharides such as sucrose, lactose, and maltose.

Question 4

What is the process called when glycosidic bonds are split?

Answer 4

Hydrolysis reactions

Hydrolysis involves the addition of water to break down glycosidic bonds in carbohydrates.

Question 5

What is the relationship between the structure of glucose and its function?

Answer 5

Structure relates to energy provision and metabolism

The structure of glucose allows it to be easily metabolized for energy.

Question 6

What is a triglyceride composed of?

Answer 6

Glycerol and three fatty acids

Triglycerides are formed by the esterification of glycerol with three fatty acids.

Question 7

What distinguishes saturated lipids from unsaturated lipids?

Answer 7

Saturated lipids have no double bonds, unsaturated lipids have one or more double bonds

Saturated lipids tend to be solid at room temperature, while unsaturated lipids are typically liquid.

Question 8

How do the structures of lipids relate to their functions?

Answer 8

Related to energy storage, waterproofing, insulation

The hydrophobic nature of lipids makes them effective for energy storage and providing insulation.

Question 9

What is the role of phospholipids in cell membranes?

Answer 9

Form the bilayer structure essential for membrane function

Phospholipids have hydrophilic heads and hydrophobic tails, creating a bilayer that serves as a barrier in cell membranes.

Question 10

What is the structure of an amino acid?

Answer 10

Central carbon, amino group, carboxyl group, R group

The R group varies among different amino acids, determining their unique properties.

Question 11

What are polypeptides formed from?

Answer 11

Amino acid monomers linked by peptide bonds

Polypeptides are formed through condensation reactions that link amino acids together.

Question 12

What types of bonding are significant in the structure of proteins?

Answer 12

Ionic, hydrogen, disulfide bonding

These bonds contribute to the overall 3D structure and stability of proteins.

Question 13

What are the four levels of protein structure?

Answer 13

Primary, secondary, tertiary, quaternary

Each level of structure contributes to the protein’s final shape and function.

Question 14

How is the structure of collagen related to its function?

Answer 14

Provides strength and support in connective tissues

Collagen’s fibrous structure allows it to withstand tensile forces.

Question 15

What is the structure of DNA composed of?

Answer 15

Nucleotides, sugar-phosphate backbones, base pairs

DNA consists of two strands forming a double helix, held together by hydrogen bonds between bases.

Question 16

What is the role of DNA helicase during replication?

Answer 16

Unwinds the DNA double helix

This enzyme separates the two strands of DNA, allowing replication to occur.

Question 17

What is a gene?

Answer 17

A sequence of bases on a DNA molecule coding for amino acids

Genes serve as templates for synthesizing proteins.

Question 18

What is the structure of mRNA?

Answer 18

Nucleotides, sugar-phosphate backbone, hydrogen bonds

mRNA is single-stranded and carries genetic information from DNA to ribosomes.

Question 19

What is the role of tRNA?

Answer 19

Brings amino acids to the ribosome during translation

tRNA has an anticodon that pairs with mRNA codons to ensure the correct amino acid sequence.

Question 20

What is transcription?

Answer 20

The process of synthesizing mRNA from a DNA template

This occurs in the nucleus and involves the enzyme RNA polymerase.

Question 21

What is the genetic code?

Answer 21

Triplets of bases coding for amino acids

The code includes start codons, stop codons, and is degenerate and non-overlapping.

Question 22

What is a gene mutation?

Answer 22

A change in the sequence of bases in a gene

Mutations can result from deletions, insertions, or substitutions of bases.

Question 23

What is the effect of point mutations?

Answer 23

Can alter amino acid sequences

An example is sickle cell anemia, which results from a single base substitution.

Question 24

What is the structure of enzymes?

Answer 24

Globular proteins

Enzymes have specific shapes that allow them to catalyze biochemical reactions.

Question 25

What is the induced fit hypothesis?

Answer 25

Enzyme changes shape to better fit the substrate ## Footnote This model explains how enzymes can be specific for their substrates.

Question 26

What do enzymes do to activation energy?

Answer 26

Reduce activation energy ## Footnote This makes reactions occur more easily and quickly.

Question 27

What factors affect enzyme activity?

Answer 27

Temperature, pH, substrate concentration, enzyme concentration ## Footnote Each of these factors can influence the rate of enzymatic reactions.

Question 28

What types of inhibition affect enzyme activity?

Answer 28

Competitive, non-competitive, end-product inhibition ## Footnote These mechanisms regulate enzyme activity in metabolic pathways.

Question 29

What is the role of nitrate ions in plants?

Answer 29

To make DNA and amino acids ## Footnote Nitrate ions are essential for plant growth and protein synthesis.

Question 30

What do calcium ions form in plants?

Answer 30

Calcium pectate for the middle lamellae ## Footnote This structure helps maintain the integrity of plant cell walls.

Question 31

What is the role of magnesium ions?

Answer 31

To produce chlorophyll ## Footnote Magnesium is a central atom in the chlorophyll molecule, essential for photosynthesis.

Question 32

What do phosphate ions contribute to in plants?

Answer 32

To make ADP and ATP ## Footnote Phosphates are crucial for energy transfer and storage in cells.

Question 33

What is the significance of water's dipole nature?

Answer 33

Leads to hydrogen bonding ## Footnote This property is vital for many biological processes and helps maintain temperature stability.

Question 34

What is the importance of water's high specific heat capacity?

Answer 34

Helps regulate temperature in organisms ## Footnote It prevents rapid temperature changes, providing a stable environment for biochemical reactions.

Question 35

What is the polar solvent property of water?

Answer 35

Dissolves many substances ## Footnote Water's polarity allows it to interact with and dissolve ionic and polar compounds.

Question 36

What is the significance of water's surface tension?

Answer 36

Allows organisms to exploit surface for movement ## Footnote High surface tension enables small organisms to walk on water.

Question 37

What does water's incompressibility contribute to?

Answer 37

Maintaining pressure in biological systems ## Footnote This property is crucial for processes like blood circulation.

Question 38

Why is maximum density of water at 4 °C important?

Answer 38

Prevents lakes from freezing solid ## Footnote This allows aquatic life to survive in winter conditions.