Solve this multiple-choice question and choose the correct option.

Stimulus–response in organisms: Movements due to light (phototactic/phototropic responses) are characteristically shown by which organism? Focus on simple motile protists in basic biology curricula. Choose the correct organism.

Difficulty: Easy

Euglena
Paramecium
Amoeba
Plasmodium

Correct Answer: Euglena

Explanation:

Concept / ApproachEuglena has a stigma (eyespot) and exhibits phototaxis (movement toward/away from light). While higher plants show phototropism, many school-level MCQs highlight phototactic movement in Euglena.

Why others are incorrectParamecium and Amoeba show taxes/kinesis to various stimuli but lack a distinct eyespot; Plasmodium is non-motile in this sense within the host.

Final AnswerEuglena shows light-directed movement.

← Previous Question Next Question→

More Questions from Biology

Genetics — definition check: What is a mutation in classical genetics? Frame the answer in terms of heritability and changes to genetic material, not recombination or environmental effects. Choose the correct definition.
Digestive enzymes: Ptyalin is an enzyme produced where in the human body? Name the secreting site associated with starch digestion initiation. Choose the correct site.
Model organisms for mutation studies: Which organism is most suitable (classically) for the study of mutations in genetics? Consider ease of culture, generation time, and visible traits. Choose the correct organism.
Animal cognition: Which mammals are widely regarded (excluding humans) as among the most highly intelligent based on problem solving, communication, and social behavior? Choose the best-supported group.
Cell biology — prokaryotes: Prokaryotic cells lack which structural feature found in eukaryotes? Answer with the defining feature absent in prokaryotes. Choose the correct feature.
Plant hormones: Name the organic substances that control plant growth and development in very small amounts. Full question: Organic substances which, even in very small concentrations, regulate growth and development in plants are called what? Choose the correct option.
Plant anatomy: Identify the group in which phloem tissue occurs. Full question: Phloem is a conducting tissue found in which type of organism? Choose the correct option.
Human nutrition: Identify the vitamin deficiency that causes night blindness. Full question: Night blindness (poor vision in dim light) is caused by a deficiency of which vitamin? Choose the correct option.
Plant nitrogen assimilation: Identify what plants convert absorbed soil nitrates into. Full question: Plants absorb dissolved nitrates (NO₃⁻) from the soil and convert them into which biomolecules? Choose the correct option.
Plant pigments: Identify the pigment responsible for most red, blue, and purple colours in plants. Full question: Most of the red, blue, and purple colours of flowers/fruits are due to which pigment group? Choose the correct option.

Discussion & Comments

No comments yet. Be the first to comment!

Join Discussion