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Lesson 2 of 13

Inside one cell

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6 min

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Look at onion skin under a microscope. Every cell has parts inside.

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The rule

DNA is the set of instructions a cell follows.

A working part inside a cell is an organelle. Each organelle has its own job. The nucleus holds the DNA. Mitochondria release energy from food.

An organelle is a part of a cell with its own job. The cytoplasm is the jelly that fills the cell. The organelles are inside it.

The membrane is the cell's edge, all around it.
Step 1 of 4
  1. The membrane is the cell's edge, all around it.
  2. The nucleus holds the DNA, inside its own edge.
  3. Mitochondria release energy from food, for the cell to use.
  4. Cytoplasm is the jelly filling the rest of the space.

Six organelles and their jobs

Proteins are large molecules that do jobs in cells. ATP is a small molecule that carries energy.

Six organelles, and the job of each
PartIts job
NucleusHolds the DNA. It controls the cell.
RibosomeMakes proteins.
Endoplasmic reticulum (ER)A network that makes and moves proteins and fats.
Golgi apparatusSorts and packs materials, then sends them out.
LysosomeBreaks down waste and worn-out parts.
MitochondrionReleases energy from food. The energy is stored in ATP.

Rough ER has ribosomes on it. Smooth ER has none.

Try the lab to finish this lesson.