What is meant by living? Give any four defining features of life forms.

Explanation

### Step-by-Step Text Solution

**Step 1: Define Living Organisms**
Living organisms are entities that exhibit certain characteristics that distinguish them from non-living things. These characteristics include the ability to evolve, self-replicate, respond to stimuli, grow, and reproduce.

**Step 2: Identify Four Defining Features of Life Forms**
1. **Cellular Organization**: Living organisms are made up of cells, which are the basic units of life. Cells can organize into tissues, organs, and systems, forming a complete organism.

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