Final answer:
The three main parts of a cell are the plasma membrane, which controls substance input and output; the cytoplasm, where metabolic activities occur; and the DNA, which contains genetic information. Additional components like ribosomes, mitochondria, peroxisomes, and the cytoskeleton support protein synthesis, energy production, detoxification, and structural integrity.
Step-by-step explanation:
The purpose of the three main parts of a cell can be described as follows:
- Plasma Membrane: This is the outer covering of the cell that separates its interior from the surrounding environment. It regulates the passage of substances in and out of the cell, thus maintaining homeostasis.
- Cytoplasm: This jelly-like substance within the cell contains all other cellular components. It's where metabolic processes occur and where the organelles reside.
- DNA: This is the genetic material that dictates all cellular functions and the cell's ability to reproduce. It contains the instructions necessary for the synthesis of proteins.
Additionally, cells contain ribosomes for protein synthesis, mitochondria for energy production (ATP), and peroxisomes for detoxifying harmful substances. The cytoskeleton, composed of microfilaments, intermediate filaments, and microtubules, provides structural support and enables cellular movement.
The nucleus, found only in eukaryotic cells, acts as the command center, housing DNA and coordinating activities such as growth, metabolism, and protein synthesis.