Quiz: Cells and Body Systems — 30 domande

1. What is the primary purpose of a microscope?

A. To produce new cells from existing cells

B. To make very small objects appear larger for study

C. To separate cells according to their chemical composition

D. To measure the temperature of microscopic specimens

Answer: (B)

Spiegazione

A microscope enlarges very small objects so that cells, microorganisms, and tiny structures can be studied.

2. Which statement correctly distinguishes a compound light microscope from an electron microscope?

A. A compound light microscope uses multiple lenses and light, whereas an electron microscope uses electrons and provides much greater magnification.

B. Both microscopes use electrons, but the compound light microscope provides greater magnification.

C. A compound light microscope uses electrons, whereas an electron microscope uses visible light and provides less magnification.

D. Both microscopes use light, but only the electron microscope uses multiple lenses.

Answer: (A)

Spiegazione

Compound light microscopes use multiple lenses and light, while electron microscopes use electrons and provide much greater magnification for viruses and tiny cell structures.

3. Which microscope part holds a slide securely on the stage?

A. The fine focus knob

B. The eyepiece lens

C. The arm

D. Stage clips

Answer: (D)

Spiegazione

Stage clips secure the slide on the stage so it remains positioned during observation.

4. Which sequence correctly describes how to set up a light microscope?

A. Carry it by the eyepiece and objective lens, place it on an angled surface, position the slide, and then turn on the light.

B. Place the slide on the stage, carry the microscope by the arm, turn on the light, and remove the stage clips.

C. Turn on the light, carry the microscope by the stage, place it on a flat surface, and position the slide without clips.

D. Carry it by the arm and base, place it on a flat surface, turn on the light, position the slide, and secure it with stage clips.

Answer: (D)

Spiegazione

Safe setup involves carrying the microscope with the arm and base, placing it flat, turning on the light, positioning the slide, and securing it with stage clips.

5. After switching from the lowest-power objective to a higher-power objective, which focusing method should be used?

A. Use the stage clips to sharpen the image.

B. Rotate the eyepiece lens to bring the image into focus.

C. Use only the fine focus knob.

D. Use the coarse focus knob before using the fine focus knob.

Answer: (C)

Spiegazione

The coarse focus is used at low power; after switching to higher power, only the fine focus knob should be used.

6. An eyepiece magnification of 10× is combined with an objective-lens magnification of 40×. What is the total magnification?

A. 400×

B. 4×

C. 40×

D. 50×

Answer: (A)

Spiegazione

Total magnification is calculated by multiplying eyepiece magnification by objective magnification: 10 × 40 = 400×.

7. Which statement best defines a cell?

A. A structure found only in organs and organ systems

B. The basic unit of life and the building block of living organisms

C. A complete organism made of several tissues

D. A group of similar cells performing a shared function

Answer: (B)

Spiegazione

A cell is the basic building block and basic unit of life; all living organisms consist of one or more cells.

8. Which statement is part of cell theory?

A. Cells are formed from organs during growth.

B. Only multicellular organisms are made of cells.

C. All tissues develop independently of cells.

D. All cells come from pre-existing cells.

Answer: (D)

Spiegazione

Cell theory states that all living things are made of cells, the cell is the basic unit of life, and all cells come from pre-existing cells.

9. What is the correct order of organisation in a multicellular organism, from simplest to most complex?

A. Cells, tissues, organs, organ systems, organism

B. Tissues, cells, organs, organism, organ systems

C. Organs, tissues, cells, organism, organ systems

D. Cells, organs, tissues, organ systems, organism

Answer: (A)

Spiegazione

Organisation in multicellular organisms increases from cells to tissues, organs, organ systems, and finally the complete organism.

10. What characterizes a unicellular organism?

A. A single cell performs all functions needed for life.

B. One organ system performs functions for many separate cells.

C. Several tissues combine to perform all functions needed for life.

D. Multiple cells specialize into organs and organ systems.

Answer: (A)

Spiegazione

A unicellular organism consists of one cell, and that single cell carries out all functions required for life.

11. What is the main role of the plasma membrane in a cell?

A. It releases energy through respiration

B. It contains the cell’s genetic material

C. It provides structural support and protection

D. It controls which substances enter and leave the cell

Answer: (D)

Spiegazione

The plasma membrane is selectively permeable, so it controls the movement of certain molecules into and out of the cell. Structural support and protection are mainly provided by the cell wall.

12. Which pairing correctly matches each cell structure with its function?

A. The nucleus makes proteins, while ribosomes store genetic material

B. The nucleus transports lipids, while ribosomes provide cell support

C. The nucleus releases energy, while ribosomes control entry and exit

D. The nucleus controls activities, while ribosomes make proteins

Answer: (D)

Spiegazione

The nucleus contains genetic material and controls cell activities, whereas ribosomes produce proteins needed for growth and repair.

13. Which statement correctly compares mitochondria and the endoplasmic reticulum?

A. Mitochondria release energy, while the endoplasmic reticulum transports materials and helps make proteins and lipids

B. Mitochondria store water, while the endoplasmic reticulum digests food particles

C. Mitochondria control cell activities, while the endoplasmic reticulum stores genetic material

D. Mitochondria make cell walls, while the endoplasmic reticulum absorbs light energy

Answer: (A)

Spiegazione

Mitochondria release energy through respiration. The endoplasmic reticulum transports materials and contributes to the production of proteins and lipids.

14. Which combination of structures is characteristic of a typical plant cell but absent from an animal cell?

A. A cell wall, vacuoles and no chloroplasts

B. Mitochondria, cytoplasm and an endoplasmic reticulum

C. A cell wall, chloroplasts and a large vacuole

D. A nucleus, ribosomes and a plasma membrane

Answer: (C)

Spiegazione

Plant cells usually contain a cell wall, chloroplasts and a large vacuole. Animal cells do not have cell walls or chloroplasts, while fungal cells have a cell wall and vacuoles but no chloroplasts.

15. What makes a cell specialised?

A. It lacks internal structures so substances can pass freely

B. It performs every function required by an organism equally

C. It is always larger than the surrounding cells

D. It is adapted for a specific function through its structure or organelles

Answer: (D)

Spiegazione

A specialised cell is adapted for a particular function through features such as its shape, number of organelles or unique structures.

16. A person consciously contracts a muscle to move an arm. Which type of muscle is responsible?

A. Skeletal muscle

B. Smooth muscle

C. Cardiac muscle

D. Digestive muscle

Answer: (A)

Spiegazione

Skeletal muscle is voluntary and moves the body. Smooth and cardiac muscles are involuntary; cardiac muscle is found only in the heart.

17. Why does the absence of a nucleus benefit a mature red blood cell?

A. It enables the cell to produce more digestive enzymes

B. It provides more space for oxygen-carrying haemoglobin

C. It allows the cell to control muscle contraction

D. It gives the cell a thicker wall for mineral transport

Answer: (B)

Spiegazione

Mature red blood cells lack a nucleus, leaving more internal space for haemoglobin. Their flexible, disc-shaped form also supports oxygen transport.

18. Which statement correctly compares root hair cells with guard cells?

A. Root hair cells absorb water and minerals, while guard cells regulate stomatal opening

B. Root hair cells release digestive enzymes, while guard cells store urine

C. Root hair cells transport sugars, while guard cells carry water through stems

D. Root hair cells produce haemoglobin, while guard cells contract the heart

Answer: (A)

Spiegazione

Root hair cells use their large surface area and thin wall to absorb water and minerals. Guard cells open and close stomata by swelling and shrinking.

19. What does homeostasis maintain in an organism?

A. A stable internal environment

B. The mechanical breakdown of food

C. The movement of food through the digestive tract

D. The production of proteins by ribosomes

Answer: (A)

Spiegazione

Homeostasis is the maintenance of stable internal conditions, including temperature, water levels, blood sugar, oxygen levels and pH. Digestion instead breaks food into absorbable molecules.

20. Which sequence shows the correct order of the main digestive tract organs?

A. Mouth, oesophagus, stomach, small intestine, large intestine, rectum

B. Mouth, stomach, oesophagus, large intestine, small intestine, rectum

C. Mouth, oesophagus, large intestine, stomach, small intestine, rectum

D. Oesophagus, mouth, stomach, small intestine, rectum, large intestine

Answer: (A)

Spiegazione

Food passes through the mouth, oesophagus, stomach, small intestine, large intestine and rectum. The liver supports digestion by producing bile.

21. How does chemical digestion differ from physical digestion?

A. Chemical digestion uses enzymes to break large molecules into smaller molecules

B. Chemical digestion absorbs water, while physical digestion filters blood

C. Chemical digestion stores food, while physical digestion produces urine

D. Chemical digestion cuts food into smaller pieces without changing its molecules

Answer: (A)

Spiegazione

Physical digestion breaks food into smaller pieces and increases its surface area. Chemical digestion uses enzymes to break large food molecules into smaller molecules.

22. Which enzyme-substrate pairing is correct?

A. Protease breaks down starch

B. Amylase breaks down fats

C. Lipase breaks down proteins

D. Amylase breaks down starch

Answer: (D)

Spiegazione

Amylase digests starch, proteases digest proteins and lipases digest fats.

23. Which structures make up the central nervous system?

A. All nerves outside the brain

B. The brain and spinal cord

C. Sensory receptors and motor neurons

D. The spinal cord and peripheral nerves

Answer: (B)

Spiegazione

The central nervous system consists of the brain and spinal cord. Nerves outside these structures belong to the peripheral nervous system.

24. What is the main function of a neuron’s long axon?

A. To carry electrical messages along the neuron

B. To detect stimuli in the environment

C. To produce hormones for target organs

D. To protect the neuron from immune responses

Answer: (A)

Spiegazione

The long axon carries electrical messages along the neuron, allowing them to travel quickly. Dendrites are associated with receiving or connecting with signals.

25. Which pathway correctly describes how information generally travels through the nervous system?

A. Stimulus, receptor, sensory neuron, central nervous system, motor neuron, response

B. Stimulus, motor neuron, receptor, central nervous system, sensory neuron, response

C. Receptor, stimulus, motor neuron, sensory neuron, central nervous system, response

D. Stimulus, central nervous system, receptor, sensory neuron, motor neuron, response

Answer: (A)

Spiegazione

Information generally follows the sequence of stimulus, receptor, sensory neuron, central nervous system, motor neuron, and response.

26. Which comparison between the nervous and endocrine systems is correct?

A. Both systems act slowly through hormones and produce long-lasting effects.

B. The nervous system acts quickly through electrical impulses, while the endocrine system acts more slowly through hormones.

C. Both systems act quickly through electrical impulses and produce short-term effects.

D. The nervous system acts slowly through hormones, while the endocrine system acts quickly through electrical impulses.

Answer: (B)

Spiegazione

The nervous system uses fast electrical impulses that usually have short-term effects, whereas the endocrine system uses slower hormones with longer-lasting effects.

27. In an organ transplant, who is the donor?

A. The person who receives the organ

B. The patient whose damaged organ remains untreated

C. The person who provides the organ

D. The doctor who performs the surgery

Answer: (C)

Spiegazione

The donor provides the healthy organ, while the recipient is the person who receives it to replace a damaged organ.

28. Why are immunosuppressant drugs commonly given after an organ transplant?

A. They increase immune attacks against infected cells only.

B. They reduce immune attacks against the transplanted organ.

C. They replace the functions of the transplanted organ.

D. They prevent the transplanted organ from receiving blood.

Answer: (B)

Spiegazione

Immunosuppressants reduce immune responses, lowering the risk that the body will reject the transplanted organ. However, they can increase infection risk and cause side effects.

29. What does dialysis do when the kidneys cannot function properly?

A. It filters waste products and excess water from the blood.

B. It completely restores all normal kidney functions.

C. It replaces the immune system’s response to transplanted organs.

D. It produces a new kidney from the patient’s own cells.

Answer: (A)

Spiegazione

Dialysis filters the blood to remove waste products and excess water. It helps when the kidneys fail but does not fully replace kidney function.

30. Which issue is an ethical concern associated with organ transplantation?

A. How limited organs should be allocated fairly

B. How hormones produce long-lasting effects

C. Whether dialysis can filter excess water

D. Whether neurons should carry electrical messages

Answer: (A)

Spiegazione

Organ shortages and fair allocation are ethical issues in transplantation, along with donor consent, fair access, and risks to living donors.