All Free Biology MCQs with Answers

• A. Lamarck
• B. Charles Darwin
• C. Herbert spencer
• D. Aristotle

Explanation: The term "survival of the fittest" was used by Herbert Spencer, an English philosopher and scientist.

• A. Vestigial organs
• B. Homologous organs
• C. Analogous organs
• D. Embryonic organs

Explanation: Vestigial organs are structures in the body that have lost or greatly reduced their original function in the course of evolution.

• A. Analogy
• B. Homology
• C. Evolutionary relationship
• D. Phylogeny

Explanation: Homology refers to the similarity in characteristics or traits between different species that is due to shared ancestry.

• A. Von bear
• B. Hackel
• C. Herbert Spencer
• D. Darwin

Explanation: Option B is correct.The principle that "ontogeny recapitulates phylogeny" was formulated by Ernst Hackel.

• A. Haemocyonin
• B. Haemoprotein
• C. Myoglobin
• D. Haemorrhoids

Explanation: A coiled haemoglobin is referred to as 'Haemoprotein' because haemoglobin is a type of haemoprotein.

• A. Magnesium
• B. Sodium
• C. Iron
• D. Potassium

Explanation: Hemoglobin is a protein in red blood cells responsible for oxygen transport.

• A. Secreted proteins
• B. Blood clotting factors
• C. Antibodies
• D. All of the above

Explanation: The correct answer is All of the above because oligosaccharides are involved in the modification and functionality of secreted proteins…

• A. Lipoprotein
• B. Nucleoprotein
• C. Glycolipid
• D. Glycoprotein

Explanation: Option D is correct.The conjugated molecule that is primarily present in egg albumin is glycoprotein.

• A. Vitamins
• B. Amino acids
• C. Nucleotides
• D. Sugar

Explanation: NAD (Nicotinamide adenine dinucleotide) is a coenzyme that plays a central role in various cellular processes, including energy…

• A. Cytoplasm
• B. Nucleus
• C. Vacuoles
• D. Nuclear pores

Explanation: The cytoplasm is the gel-like fluid inside the cell. It is the medium for chemical reactions.

• A. Proteins
• B. Carbohydrates
• C. Phospholipids
• D. Terpendoids

Explanation: rough endoplasmic reticulum (RER), a series of connected flattened sacs, part of a continuous membrane organelle within the cytoplasm of…

• A. lysosomes
• B. ribosome
• C. rough endoplasmic reticulum
• D. smooth endoplasmic reticulum

Explanation: The cell organelle responsible for the detoxification of waste substances is the smooth endoplasmic reticulum.

• A. Peroxisomes
• B. Lysosomes
• C. Glyoxisomes
• D. Ribosomes

Explanation: Glyoxisomes are specialized organelles found only in plants. These contain enzymes for the glyoxylate cycle, through which fats are…

• A. A (outer membrane) - regulates molecule passage
• B. B (inner membrane) - forms infoldings called cristae
• C. C (crista) - site of Glycolysis.
• D. D (matrix) - site of Anaerobic fermentation.

Explanation: The correct answer is B (inner membrane) - forms infoldings called cristae.

• A. Sodium ions
• B. Calcium ions
• C. Potassium ions
• D. Magnesium ions

Explanation: The correct answer is Option D: Magnesium ions. Magnesium ions play a crucial role in stabilizing the ribosome-mRNA complex by…

• A. Chloroplastids
• B. Proplastids
• C. Chromoplastids
• D. Leucoplastids

Explanation: All types of plastids are produced from proplastids. Proplastids are undifferentiated, non-pigmented plastids that serve as the precursor…

• A. Glyoxisome
• B. Bile juice
• C. Pancreatic juice
• D. Lysosomes

Explanation: Glyoxisomes are specialized organelles found in plant cells and some microorganisms.

• A. Enzymes
• B. Protein
• C. Sugar
• D. Lipids

Explanation: The smooth endoplasmic reticulum (SER) is primarily responsible for the synthesis of lipids, which include phospholipids, cholesterol, and…

• A. Golgi-Apparatus
• B. Lysosomes
• C. Peroxisomes
• D. Glyoxisomes

Explanation: Lysosomes perform phagocytosis, pinocutosis and autophagy as they contain enzymes to digest foreign material and casue cell death.

• A. Stroma
• B. Grana
• C. Thylakoid membrane
• D. Crista

Explanation: The correct answer is the thylakoid membrane. This is where the pigments chlorophyll a, b, and carotenoids are located, as they are…