📚 CBSE Grade-10 Study Guide
HomeScience (086) (AI practice)

Science (086) — AI-generated practice question

AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.

Q1. [2] medium thorough-understanding
Both the nervous system and the endocrine system help animals respond to changes in the environment, yet the body uses hormones rather than nerve impulses to prepare for a fight-or-flight response. Justify this choice by comparing the two systems in terms of the speed, reach, and duration of their effects.
Generated by claude-sonnet-4-6 · 2026-06-26 01:02 · grounding rag
Model Answer

Nerve impulses act quickly but over a limited range — only tissues connected by nerves receive the signal. For fight-or-flight, the body needs to prepare many different tissue types simultaneously (heart, muscles, lungs, digestive system). Adrenaline, released into the blood, reaches all cells of the body, producing wide-ranging changes. Its effects also last longer, sustaining readiness until the threat passes. Hence, hormonal control is better suited for this response.

Source: Chapter 6, Section 6.3 — Hormones in Animals

---

Explanation

The examiner wants you to hit three comparison points — speed, reach, duration — and link each to why hormones win for fight-or-flight. The key textbook line is: "If the body design relied only on electrical impulses, the range of tissues instructed would be limited; a chemical signal would reach all cells." Mention adrenaline by name. Don't just describe what adrenaline does — explain why the chemical route is chosen over nerve impulses. Two well-linked points with the justification will earn full marks.

Previous-year CBSE Grade 10 board exam questions, organised by subject and chapter, each with a model answer — free to read and print.