alleryStart learning →Which ions enter guard cells to help open stomata?
- Sodium ions
- Potassium ions
- Calcium ions
- Iron ions
Show answer and solution
Correct answer: B. Potassium ions
Potassium uptake increases solute concentration in guard cells, helping water enter.
ICSE Class 10 Plant Physiology: transpiration — practice questions — page 2
Explore 54 free Plant Physiology: transpiration questions in ICSE Class 10 Biology. Open each question or exercise to read its content, reference answers and available explanation.
Practise Plant Physiology: transpiration with Quill →Plant Physiology: transpiration questions and exercises with answers
Showing questions 31–54 of 54.
Which ions enter guard cells to help open stomata?Read the answer and worked solution →What happens when potassium leaves guard cells?Read the answer and worked solution →Which hormone helps close stomata during drought?Read the answer and worked solution →What does stomatal closure during drought help reduce?Read the answer and worked solution →What surrounds each stoma and helps control it?Read the answer and worked solution →How are guard cells arranged around a pore?Read the answer and worked solution →Which side of a guard cell is thicker?Read the answer and worked solution →Why does a turgid guard cell bend outward?Read the answer and worked solution →What is transpiration stream water replaced by?Read the answer and worked solution →What does cavitation do to xylem water transport?Read the answer and worked solution →When may cavitation occur?Read the answer and worked solution →What can a plant do overnight to help refill cavitated xylem?Read the answer and worked solution →What is the source of water that exits through stomata?Read the answer and worked solution →What can close stomata when water loss exceeds root uptake?Read the answer and worked solution →What does closing stomata trade off during drought?Read the answer and worked solution →A high humidity gradient at a leaf pore helps determine what?Read the answer and worked solution →Where is water vapour inside a leaf before it exits?Read the answer and worked solution →How does transpiration affect plant nutrient flow?Read the answer and worked solution →Which structural adaptation helps desert plants reduce water loss?Read the answer and worked solution →Why do open stomata cause gas gain and water loss?Read the answer and worked solution →Match each pathway of plant transpiration with the organ through which water vapor is lost:Read the answer and worked solution →Match each mechanism of stomatal regulation with its physiological trigger:Read the answer and worked solution →Match each environmental factor with its effect on transpiration rate:Read the answer and worked solution →Match each physiological water loss term with its distinct botanical definition:Read the answer and worked solution →
Worked practice questions
What happens when potassium leaves guard cells?
- Water enters the root hair
- Stomatal pores widen
- Stomatal pores close
- The leaf begins mitosis
Show answer and solution
Correct answer: C. Stomatal pores close
Potassium release draws water out and causes stomatal closure.
Which hormone helps close stomata during drought?
- Auxin hormone
- Gibberellin
- Cytokinin
- Abscisic acid
Show answer and solution
Correct answer: D. Abscisic acid
Abscisic acid is produced in response to drought and triggers stomatal closure.
How to practise
- Choose a Plant Physiology: transpiration question and try to work out your answer.
- Open the question to check the correct answer and read its worked solution.
- Continue in the app for bite-sized lessons, explanations and review with Quill. You can start without creating an account.
Put it into practice
Continue with Plant Physiology: transpiration practice for ICSE Class 10. Read explanations as you go. No signup form needed to start.
Practise Plant Physiology: transpiration →