IB myp 4-5 Biology – Practice Questions- All Topics
Topic :Cells-Tissues
Topic :Cells– Weightage : 21 %
All Questions for Topic : Tissues,Organs,System,Structure and Function,Life processes,Factors affecting human health,Vaccination
Question
What is smallest unit of life (1 mark)
▶️Answer/Explanation
Cells are the smallest unit of life
Question:
Formulate a hypothesis regarding which of these extra structures are needed in the cells below so they can perform their functions:
a) Cells forming the lining of the small intestine, where digested foods are absorbed.
▶️Answer/Explanation
Ans: Microvilli, vesicles, pseudopodia.
b) White blood cells that fight disease by moving into infected tissue and engulfing the organisms causing the infection.
▶️Answer/Explanation
Ans: Lysosomes, actin and myosin filaments, pseudopodia.
c) Neurons that transmit nerve impulses and send signals across synapses from one neuron to another.
▶️Answer/Explanation
Ans: Vesicles.
d) Cells that develop into hair or nail.
▶️Answer/Explanation
Ans: Keratin fibres, microtubules.
Question:
The photos (I–IV) shown here are electron micrographs of the four cell types in the previous question. Apply your scientific knowledge to deduce the cell type in each photo and what cell structures are visible.
▶️Answer/Explanation
Ans: I is nerve endings/synapses in a neuron.
II is a white blood cell that has engulfed disease–causing microbes.
III is a cell that is developing into cornified skin.
IV is cells in the lining of the small intestine that absorb digested food.