All Free Biology MCQs with Answers

• A. Electronegative oxygen
• B. Nitrogen atom
• C. Sulphur
• D. Both A and B

Explanation: Most contain nitrogen, and some also contain sulfur or cobalt or oxygen except carbon, hydrogen elements.

• A. Vitamin C
• B. Vitamin B
• C. Both options A and B are correct
• D. None of these options is correct

Explanation: Vitamin B1 (thiamine) and vitamin B2 (riboflavin) are generally non-toxic.

• A. Carbohydrates
• B. Proteins
• C. Lipids
• D. All of these

Explanation: Large organic molecules are composed of many atoms, and they are often referred to as macromolecules.

• A. UTP
• B. FAD
• C. NAD
• D. ATP

Explanation: The most abundant free nucleotide in mammalian cells is ATP.

• A. H
• B. N and O
• C. S
• D. All of the above options are correct

Explanation: Carbon can bind to H, O, N, and S and form many important structural and functional components of a living organism.

• A. Convergent evolution
• B. Divergent evolution
• C. Coevolution
• D. Parallel evolution

Explanation: The pattern of evolution in which different species have evolved from different ancestors in a common habitat is known as convergent…

• A. Homologous organs
• B. Analogous organs
• C. Vestigial organs
• D. Saltatory organs
• E. Vital organs

Explanation: Explanation for this question will be added soon.

• A. Natural selection
• B. Artificial selection
• C. Evolution
• D. Genetic drif

Explanation: When humans purposefully apply selection pressure to populations, such as in breeding programs for plants or animals, it is known as…

• A. Amphibians and reptiles
• B. Reptiles and birds
• C. Birds and mammals
• D. None of these

Explanation: Archaeopteryx is known to be a communicating connection between reptiles and birds because it looks like a bird and has bird wings.

• A. Analogous organs
• B. Homologous organs
• C. Convergent organs
• D. Divergent organs

Explanation: Analogous organs are similar in function but different in structure. These organs have evolved independently in different species to…

• A. Darwin's theory of evolution
• B. Lamarckism
• C. Neo-darwinism
• D. Endosymbiont Hypothesis

Explanation: This statement aligns with the endosymbiotic theory, which suggests that mitochondria and chloroplasts were once free-living bacteria that…

• A. Organisms ranged from simple to complex.
• B. One type of organism gives rise to another type of organism.
• C. Both a and b.
• D. All living things are specially created by nature.

Explanation: During Aristotle's time, it was though that organisms ranged from simple to complex. All other options are incorrect.

• A. Organisms ranged from simple to complex
• B. One type of organism gives rise to another type of organism
• C. Both Options A and B are correct
• D. Only living things are created by nature

Explanation: In Aristotle's time, with respect to the theory of inheritance, it was already known that organisms varied on the basis of their…

• A. Fe2+
• B. Mg2+
• C. Mn2+
• D. Ca2+

Explanation: The chlorophyll molecule consists of a central magnesium atom surrounded by a nitrogen- containing structure called a porphyrin ring…

• A. Proteins and carbohydrates
• B. Fats and proteins
• C. Fats and carbohydrates
• D. Vitamins and fats

Explanation: 'Chylomicrons' are a type of lipoprotein. As the name suggests, lipo- means lipids and proteins.

• A. Serine
• B. Choline
• C. Inositol
• D. Ethanolamine

Explanation: 'Lecithin', also called Phosphatidylcholine, is a group of phospholipids (phosphoglycerides) that are important in cell structure and…

• A. Lipoproteins
• B. Glycolipids
• C. Sphingolipids
• D. Glycoproteins

Explanation: Cell-surface markers are glycoproteins that are able to respond to or sense the environment around the cell and contain receptors that…

• A. Glycoproteins
• B. Lipids
• C. Phospholipids
• D. Nucleoprotiens

Explanation: The nucleoprotein of negative-strand RNA viruses forms a major component of the ribonucleoprotein complex that is responsible for viral…

• A. Glycoproteins
• B. Glycolipids
• C. Nucleohistones
• D. Carbohydrates

Explanation: Any protein molecule with a carbohydrate attached is known as a glycoprotein.

• A. They are conjugated molecules of carbohydrates
• B. Both have role in the extracellular matrix of animals and bacterial cell wall
• C. They are components of biological membranes.
• D. Both are produced and secreted by endoplasmic reticulum

Explanation: D is correct because glycoprotein and glycolipids are secreted by golgi apparatus .It also modifies these conjugated molecules.