Biological Molecules | Biology | Target Mdcat 2025

Question 1

Which of the following has the lowest melting point?

All fats

Triglycerides

Gingelly oil

All

Question 2

The secondary structure of proteins is primarily maintained by ___ bonds.

Glycosidic

Peptide

Ester

Hydrogen

Question 3

The molecular formula for tristearin (a triglyceride) is:

C₅₇H₁₁₀O₅

C₅₇H₁₁₀O₆

C₅₆H₁₁₁O₈

C₅₅H₁₁₂O₇

Question 4

A phospholipid contains:

A phosphorous atom

A phosphorylated group

Both

None

Question 5

Which amino acid is neutral at physiological pH?

Valine

Serine

Alanines

All

Question 6

Lipids are generally ______ in water.

Insoluble

Soluble

Partially soluble

None

Question 7

Which element is NOT found in carbohydrates?

Carbon

Oxygen

Nitrogen

Hydrogen

Question 8

How does biochemistry explain complex organ formation?

By studying molecular interactions between cells

By analyzing genetic variations

By synthesizing artificial organs

None

Question 9

Which protein functions as a secondary structure?

Antibodies

Hormones

Collagen

Hemoglobin

Question 10

Fatty acids are classified based on:

Saturated (no double bonds); Unsaturated (double bonds)

Unsaturated; Saturated

Both can be saturated

Neither

Question 11

The suffix '-ose' indicates that a substance is a:

Lipid

Protein

Sugar

Nucleic acid

Question 12

Palmitic acid contains ______ carbon atoms (including the carboxyl carbon):

16

15

14

12

Question 13

Which group of amino acids is aromatic?

Tyrosine; Phenylalanine

Tyrosine; Tryptophan; Glutamic acid

Glutamic acid; Lysine; Valine

None

Question 14

Guanine always pairs with:

Thymine

Adenine

Cytosine

Uracil

Question 15

Nucleic acids are polymers of:

Nucleotides & nucleosides

Nucleosides only

Nucleotides only

Nucleotides & phosphate groups

Question 16

Water’s high heat of vaporization is due to:

474 cal/g

547 cal/g

447 cal/g

574 cal/g

Question 17

The R-group in lipids can be:

Simple alkyl groups

Complex groups

Long hydrocarbon chains

All

Question 18

Neural tissue lipids have a ______ structure:

More complex

Less complex

Simple

Variable

Question 19

Amino acid structure changes with:

pH; pH

pH; structure

structure; pH

Both

Question 20

Which of the following statements about amino acids is correct?

All amino acids are essential

All amino acids are non-essential

All amino acids are alpha amino acids

All amino acids have the same side chains

Question 21

A characteristic feature of unsaturated fatty acids is:

Absence of double bonds

Presence of triple bonds

Presence of double bonds

Absence of triple bonds

Question 22

Which of the following is a reducing sugar?

Sucrose

Maltose

Cellulose

Starch

Question 23

The bond between monosaccharides in disaccharides is called:

Peptide bond

Phosphodiester bond

Glycosidic bond

Hydrogen bond

Question 24

Which is not a function of proteins?

Enzyme catalysis

Energy storage

Transport

Structural support

Question 25

Hemoglobin is a:

Monomeric protein

Tetrameric protein

Trimeric protein

Dimeric protein

Question 26

Which vitamin is essential for blood clotting?

Vitamin A

Vitamin B12

Vitamin D

Vitamin K

Question 27

Which element is found in all amino acids but not in carbohydrates?

Oxygen

Hydrogen

Carbon

Nitrogen

Question 28

Which of the following is a saturated fatty acid?

Oleic acid

Linoleic acid

Stearic acid

Arachidonic acid

Question 29

Which macromolecule has a primary, secondary, tertiary, and quaternary structure?

Carbohydrates

Lipids

Proteins

Nucleic acids

Question 30

Which of the following is not a disaccharide?

Lactose

Maltose

Sucrose

Cellulose

Question 31

A phosphodiester bond is found in:

Nucleic acids

Lipids

Carbohydrates

Proteins

Question 32

The most abundant protein in the human body is:

Hemoglobin

Collagen

Keratin

Myosin