Kundali IQHome › Exam notes › CTET › Life Processes
Life Processes
Five Subject Roadmaps
Useful for: CTET, OTET, OSSTET, CSIR NET, CTSA / STSS, Junior Teacher, OAVS, OSEPA Upper Primary — Science
Overview
Life processes — nutrition, respiration, transportation and excretion — maintain living organisms.
Key points
- Autotrophs make their own food by photosynthesis; heterotrophs depend on others.
- Aerobic respiration: glucose + oxygen → carbon dioxide + water + energy.
- Anaerobic respiration in yeast produces ethanol and CO₂; in muscles it produces lactic acid.
- Humans have double circulation through a four-chambered heart.
- Xylem carries water; phloem carries food.
- The nephron is the functional unit of the kidney.
Explanation
- Stomata exchange gases and lose water (transpiration).
- Villi increase absorption in the small intestine.
- Haemoglobin carries oxygen.
- Plants excrete through leaves falling and stored wastes.
- Muscle cramps follow lactic acid build-up.
Step by step
- Identify the concept or reaction.
- Recall the definition, equation or example.
- Check balance, units and direction.
Examples
- Yeast in dough makes it rise → anaerobic respiration releasing CO₂.
- Water rises in a plant stem → xylem transport.
- Urine is formed in → nephrons.
Traps and advanced points
- Trap: Mixing aerobic and anaerobic products.
- Trap: Xylem/phloem swap.
- Trap: Single circulation in humans.
Quick revision
- Four life processes.
- Aerobic vs anaerobic products.
- Double circulation; nephron.
Practice MCQs
The functional unit of the kidney is the —
- alveolus
- villus
- neuron
- nephron
Read chapter notes · Similar questions
Show answer
Answer: (d) nephron. Urine is formed in nephrons.
Aerobic respiration produces —
- ethanol
- lactic acid
- carbon dioxide, water and energy
- only oxygen
Read chapter notes · Similar questions
Show answer
Answer: (c) carbon dioxide, water and energy. Glucose + oxygen → CO₂ + water + energy.
Yeast respiring without oxygen produces —
- ethanol and carbon dioxide
- only water
- glucose
- lactic acid
Read chapter notes · Similar questions
Show answer
Answer: (a) ethanol and carbon dioxide. Anaerobic respiration in yeast gives ethanol and CO₂.
Muscle cramps after heavy exercise are due to —
- ethanol
- lactic acid
- oxygen
- glucose
Read chapter notes · Similar questions
Show answer
Answer: (b) lactic acid. Anaerobic respiration in muscles forms lactic acid.
Xylem carries —
- water and minerals
- hormones only
- oxygen only
- food
Read chapter notes · Similar questions
Show answer
Answer: (a) water and minerals. Phloem carries food; xylem carries water.
Humans have double circulation because the heart has —
- one chamber
- three chambers
- two chambers
- four chambers that separate oxygenated and deoxygenated blood
Read chapter notes · Similar questions
Show answer
Answer: (d) four chambers that separate oxygenated and deoxygenated blood. Blood passes through the heart twice in one cycle.
Absorption of digested food mainly occurs in the —
- small intestine
- large intestine
- oesophagus
- stomach
Read chapter notes · Similar questions
Show answer
Answer: (a) small intestine. Villi in the small intestine absorb nutrients.
Haemoglobin mainly carries —
- urea
- carbon dioxide only
- oxygen
- glucose
Read chapter notes · Similar questions
Show answer
Answer: (c) oxygen. Haemoglobin carries oxygen.
Loss of water from leaves through stomata is —
- respiration
- excretion
- digestion
- transpiration
Read chapter notes · Similar questions
Show answer
Answer: (d) transpiration. Transpiration pulls water up the xylem.
Green plants are —
- autotrophs
- parasites
- saprophytes
- heterotrophs
Read chapter notes · Similar questions
Show answer
Answer: (a) autotrophs. They make food by photosynthesis.
More topics in this chapter
Notes and questions are written by Kundali IQ for practice. They are not official papers; always check the latest official notification for the syllabus and pattern.