IB Biology HL Questions and Answers
| Latest Version | 2025/2026 | Correct &
Verified
What organisms are primary consumers?
✔✔ Herbivores
What is biomass?
✔✔ Total mass of living material
Why is energy lost between trophic levels?
✔✔ Used in respiration and lost as heat
What is the carbon cycle?
✔✔ Movement of carbon through ecosystems
What process releases carbon dioxide from organisms?
✔✔ Respiration
What process removes carbon dioxide from the atmosphere?
✔✔ Photosynthesis
What gas causes the greenhouse effect?
1
,✔✔ Carbon dioxide
What is homeostasis?
✔✔ Maintenance of stable internal conditions
What hormone regulates blood glucose?
✔✔ Insulin
What organ controls hormonal regulation?
✔✔ Pituitary gland
What system responds quickly using electrical signals?
✔✔ Nervous system
What type of immunity is gained after vaccination?
✔✔ Active immunity
What are antibodies?
✔✔ Proteins that bind to antigens
What is an antigen?
✔✔ A foreign molecule that triggers immune response
2
,What is apoptosis?
✔✔ Programmed cell death
What is the main goal of cell division?
✔✔ Growth, repair, and reproduction
What is the basic unit of life?
✔✔ The cell
What molecule stores genetic information?
✔✔ DNA
What is the role of ribosomes?
✔✔ Protein synthesis
Which organelle produces ATP in eukaryotic cells?
✔✔ Mitochondria
What process converts glucose into usable energy?
✔✔ Cellular respiration
3
, What is the chemical formula of glucose?
✔✔ C₆H₁₂O₆
What type of bond joins amino acids together?
✔✔ Peptide bond
What level of protein structure is determined by amino acid sequence?
✔✔ Primary structure
What enzyme breaks down starch into maltose?
✔✔ Amylase
What is the function of enzymes?
✔✔ To speed up chemical reactions
What factor can denature an enzyme?
✔✔ Extreme temperature or pH
What is diffusion?
✔✔ Movement of particles from high to low concentration
What process requires energy to move substances across membranes?
4
| Latest Version | 2025/2026 | Correct &
Verified
What organisms are primary consumers?
✔✔ Herbivores
What is biomass?
✔✔ Total mass of living material
Why is energy lost between trophic levels?
✔✔ Used in respiration and lost as heat
What is the carbon cycle?
✔✔ Movement of carbon through ecosystems
What process releases carbon dioxide from organisms?
✔✔ Respiration
What process removes carbon dioxide from the atmosphere?
✔✔ Photosynthesis
What gas causes the greenhouse effect?
1
,✔✔ Carbon dioxide
What is homeostasis?
✔✔ Maintenance of stable internal conditions
What hormone regulates blood glucose?
✔✔ Insulin
What organ controls hormonal regulation?
✔✔ Pituitary gland
What system responds quickly using electrical signals?
✔✔ Nervous system
What type of immunity is gained after vaccination?
✔✔ Active immunity
What are antibodies?
✔✔ Proteins that bind to antigens
What is an antigen?
✔✔ A foreign molecule that triggers immune response
2
,What is apoptosis?
✔✔ Programmed cell death
What is the main goal of cell division?
✔✔ Growth, repair, and reproduction
What is the basic unit of life?
✔✔ The cell
What molecule stores genetic information?
✔✔ DNA
What is the role of ribosomes?
✔✔ Protein synthesis
Which organelle produces ATP in eukaryotic cells?
✔✔ Mitochondria
What process converts glucose into usable energy?
✔✔ Cellular respiration
3
, What is the chemical formula of glucose?
✔✔ C₆H₁₂O₆
What type of bond joins amino acids together?
✔✔ Peptide bond
What level of protein structure is determined by amino acid sequence?
✔✔ Primary structure
What enzyme breaks down starch into maltose?
✔✔ Amylase
What is the function of enzymes?
✔✔ To speed up chemical reactions
What factor can denature an enzyme?
✔✔ Extreme temperature or pH
What is diffusion?
✔✔ Movement of particles from high to low concentration
What process requires energy to move substances across membranes?
4
