Biology

Unit 2 Notes: Organelles

(1) What is an organelle?

• An organelle is a small structure inside a cell.

• Each organelle has a unique structure and function within that cell.

• Cells rely on organelles to complete the living characteristics, and maintain homeostasis.

(2) The Nucleus

• FUNCTION: Store and protect the cell’s genetic information (or DNA).

• What does it look like?• A larger ball / sphere.

• Has tiny holes (or pores) on the outside of it for DNA to leave during important processes.

(3) The Endoplasmic Reticulum

• FUNCTION: Produce Lipids and Hormones, and then ship lipids—hormones—and proteins to their proper location inside the cell.

• What does it look like?• Uneven, branched rows (like a maze).

• Directly surrounds the nucleus.

(4) The Golgi Body / Apparatus

• FUNCTION: Package, Sort, and Ship the different biomolecules and enzymes/proteins to their proper destination inside the cell (or outside to another cell).

• What does it look like?• Squiggly layers of pancakes.

• Directly near the edge of the cell.

(5) The Mitochondria

• FUNCTION: Produce ATP for the cell using Cellular Respiration.

• What does it look like?• Kidney bean with a squiggly line inside of it.

(6) The Lysozome

• FUNCTION: Contain digestive enzymes to break down useless/non-functioning cell parts.

• What does it look like?• A small sphere.

• May have dots inside to represent its enzymes.

• Same as a Peroxisome.

(7) The Cell Membrane

• FUNCTION: Control what enters and exits the cell, along with providing minimal cell structure/shape.

• What does it look like?• The outer-covering of the cell.

• Looks like the line drawn around to represent the cell.

(8) The Centrosome

• FUNCTION: Help organize DNA strands during Cell Division.

• What does it look like?• Bundles of churros / sticks / tubes.

(9) The Cytoplasm

• FUNCTION: Hold all organelles, and allow for molecules to move throughout the cell.

• What does it look like?• Has no appearance on paper.

• It is the “filling” of a cell.

• We would say it looks like the “empty space” in a cell.

(10) Small Vacuoles & Vesicles

• FUNCTION: Store molecules (like sugars, proteins, salts, enzymes) until they reach their final destination or are used.

• What does it look like?• Tiny bubbles.

(11) The Ribosome

• FUNCTION: Connect amino acids together to form complex proteins (or polypeptides).

• What does it look like?• Tiny dots.

• You’ll find them floating around the inside of the cell, and on the endoplasmic reticulum.

(12) Special Organelles to Plants• Cell Wall:

• FUNCTION: Provide extra structure, support and protection to the outside of the cell.• What does it look like?

An extra, more boxy covering on the outside of a plant cell.

• Chloroplast:• FUNCTION: Convert unusable light-energy into chemical potential energy stored in sugar, using

Photosynthesis.• What does it look like?

A bean with stacks of discs on the inside.

• Enlarged Vacuole:• FUNCTION: Store extra water for plants to use during Photosynthesis, and to also help maintain

rigidity.• What does it look like?

A giant bubble.

(13) Special Organelles to Animals• Peroxisome:

• FUNCTION: Break down harmful hydrogen peroxide produced in the cell, using the enzyme catalase.

• What does it look like?A small sphere.May have dots inside to represent its enzymes.Same as a Lysosome.