---
title: Unraveling the Secrets of Life: A Deep Dive into Nutrition in Animals and Plants (Class 7 Science)
slug: class-7-science-nutrition-in-animals-and-plants
source: https://www.swavid.com/blogs/class-7-science-nutrition-in-animals-and-plants
---

# Unraveling the Secrets of Life: A Deep Dive into Nutrition in Animals and Plants (Class 7 Science)

## Quick Answer
Nutrition is the fundamental process by which all living organisms obtain and utilize food for growth, repair, reproduction, and essential life functions. This article explains how plants, as autotrophs, produce their own food primarily through photosynthesis, and how animals, as heterotrophs, acquire nutrients by consuming other organisms, detailing their diverse digestive processes.

## Who This Helps
*   Class 7 science students studying biology and life processes.
*   Educators seeking clear explanations of nutrition in plants and animals.
*   Individuals interested in understanding basic biological concepts of food acquisition and utilization.
*   Anyone preparing for exams on fundamental science topics related to living organisms.

## Key Takeaways
*   Nutrition is essential for all life, enabling growth, repair, and reproduction.
*   Plants are autotrophs, producing their own food, mainly via photosynthesis.
*   Photosynthesis uses sunlight, carbon dioxide, and water to create glucose and oxygen.
*   Animals are heterotrophs, obtaining nutrients by consuming other organisms.
*   Holozoic nutrition in animals involves ingestion, digestion, absorption, assimilation, and egestion.
*   The human digestive system is a complex alimentary canal with specialized organs and enzymes.
*   Ruminants possess a unique four-chambered stomach for digesting tough plant material.
*   Plants and animals are interconnected through nutrient cycles and energy flow.

## What People Usually Ask
### What is nutrition in living organisms?
Nutrition is the process by which organisms obtain and use food to support life functions like growth, repair, and energy production.

### How do plants get their food?
Plants primarily get their food through photosynthesis, a process where they convert sunlight, carbon dioxide, and water into glucose (food) and oxygen.

### What is photosynthesis?
Photosynthesis is the process green plants and some other organisms use to synthesize nutrients from carbon dioxide and water, using sunlight as an energy source.

### How do animals obtain nutrients?
Animals obtain nutrients by consuming other organisms (plants, other animals, or both), a mode of nutrition known as heterotrophic nutrition.

### What are the main types of animal nutrition?
Animals exhibit heterotrophic nutrition, categorized as herbivores (plant-eaters), carnivores (meat-eaters), and omnivores (eaters of both plants and animals).

### What are the five steps of holozoic nutrition?
The five steps of holozoic nutrition are ingestion (taking in food), digestion (breaking down food), absorption (nutrient uptake), assimilation (nutrient utilization), and egestion (waste elimination).

### How does the human digestive system work?
The human digestive system breaks down food mechanically and chemically in organs like the mouth, stomach, and small intestine, absorbing nutrients into the bloodstream and eliminating waste.

### Why do cows chew their cud?
Cows (ruminants) chew their cud to re-chew partially digested plant material, allowing specialized microbes in their rumen to further break down tough cellulose for nutrient extraction.

## FAQ
### What is the difference between autotrophic and heterotrophic nutrition?
Autotrophic nutrition is when organisms, like plants, produce their own food from simple inorganic substances, typically through photosynthesis. Heterotrophic nutrition is when organisms, like animals, obtain food by consuming other living organisms or organic matter.

### What are the raw materials required for photosynthesis?
The raw materials for photosynthesis are carbon dioxide (absorbed from the atmosphere), water (absorbed from the soil), and sunlight (energy source). Chlorophyll, the green pigment, is also essential for trapping solar energy.

### Where does photosynthesis primarily occur in a plant?
Photosynthesis primarily occurs in the chloroplasts, specialized organelles found within the cells of green leaves and other green parts of the plant. Chlorophyll inside the chloroplasts absorbs sunlight.

### What is the role of chlorophyll in photosynthesis?
Chlorophyll is the green pigment in plants that absorbs light energy from the sun. This absorbed energy is then used to power the chemical reaction that converts carbon dioxide and water into glucose and oxygen.

### What are villi, and what is their function in human digestion?
Villi are tiny, finger-like projections lining the inner surface of the small intestine. Their primary function is to significantly increase the surface area available for the absorption of digested nutrients into the bloodstream and lymph.

### What is peristalsis in the digestive system?
Peristalsis is the rhythmic, wave-like contractions and relaxations of the muscular walls of the alimentary canal (like the esophagus and intestines). This involuntary movement propels food along the digestive tract.

### How do parasitic plants obtain their nutrition?
Parasitic plants, such as Cuscuta (Dodder), lack chlorophyll and cannot perform photosynthesis. They obtain their nutrition by attaching to a host plant and inserting specialized structures called haustoria into the host's tissues to absorb prepared food and nutrients.