Life Processes, Control & Coordination Quiz

Plants absorb water through their roots and transport it to leaves where photosynthesis occurs. Simultaneously, oxygen produced in the leaves diffuses out, and carbon dioxide diffuses in. Which of the following structures are involved in both transport and exchange processes?

1. Root hair cells and stomata
2. Xylem and phloem
3. Xylem and vacoule
4. Stomata and guard cells

Answer: (a) Root hair cells and stomata

Given below is the diagram of a single-celled organism. The arrows represent the movement of substances such as in and out of the cell. Which combination of life processes is most accurately represented by these movements?

1. Digestion, coordination, and reproduction
2. Coordination, digestion, and excretion
3. Excretion, transport, and respiration
4. Immunity, digestion, and movement

Answer: (c) Excretion, transport, and respiration

Farmers are advised to water their crops early in the morning rather than in the evening. Which combination of biological processes explains this practice?

1. Water absorption, stomatal closure, and respiration
2. Transpiration, nutrient absorption, and photosynthesis
3. Photosynthesis, evaporation, and osmotic diffusion
4. Evaporation, osmoregulation, and nutrient transport

Answer: (b) Transpiration, nutrient absorption, and photosynthesis

In the diagram of root cells below, water moves between regions due to differences in water concentration. In which direction would the net flow of water be the greatest?

1. C to B
2. B to C
3. A to C
4. A to B

Answer: (a) C to B

The table below shows the oxygen consumption rates in different tissues of a mammal during rest and physical activity. From the data, what conclusion can you draw about respiration in these tissues? Tissue Oxygen Consumption at Rest (mL/min) Oxygen Consumption During Activity (mL/min) Heart 8 20 Skeletal Muscles 12 60 Brain 15 15

1. Skeletal muscles rely on anaerobic respiration at rest.
2. The heart's oxygen consumption doubles due to increased blood pressure.
3. Skeletal muscles generate more energy than the brain at rest.
4. The brain has a consistent oxygen demand regardless of activity.

Answer: (d) The brain has a consistent oxygen demand regardless of activity.

A table summarises the effect of plant hormones under different conditions. Identify the incorrect pairing. Hormone Effect A Cytokinins Delay in leaf senescence B Abscisic Acid Induces seed dormancy C Ethylene Promotes root elongation D Gibberellins Stimulates stem elongation

1. A
2. B
3. C
4. D

Answer: (c) C

In the following diagram, nerve cell A is communicating with nerve cell B. What structures on the membrane of nerve cell B enable it to detect the message from nerve cell A?

1. Axon
2. Ion channels
3. Dendrites
4. Receptor proteins

Answer: (d) Receptor proteins

A student accidentally touches a hot iron and immediately withdraws their hand. This action is described as a reflex. Which of the following explains why this action occurs rapidly without conscious thought?

1. The response bypasses the central nervous system entirely.
2. The brain delays the response until pain is felt.
3. The signal is processed only in the spinal cord.
4. The sensory neuron directly connects to the motor neuron.

Answer: (c) The signal is processed only in the spinal cord.

The table below describes homeostatic processes associated with specific organs. Select the correct option (1, 2, 3) to complete the missing parts of the table. Organ/System Stimulus Mechanism Outcome Kidneys Increase in blood osmolarity 1 Production of concentrated urine Skin Increase in environmental temperature Sweating and vasodilation 2 Hypothalamus Drop in core body temperature 3 Heat production via shivering

1. Reabsorption of water, Cooling of skin, Vasodilation
2. Secretion of ADH, Temperature stabilisation, Movement of muscles
3. Water filtration, Evaporative cooling, Vasoconstriction
4. ADH release, Stabilisation of body temperature, Increased metabolism

Answer: (b) Secretion of ADH, Temperature stabilisation, Movement of muscles

Study the flowchart given below and based on your understanding identify which of the following human processes is represented by the diagram?

1. Cell respiration
2. Coordination
3. Nutrient absorption
4. Reflex action

Answer: (b) Coordination