Science Starter #2 – 10/11/16

•What are four components that ALL cells share?

NOTES 3.2: CELL PARTS

Chapter 4 pages 77-90

The Parts of the Cell

Organelles

--Structure within a cell that performs a certain function

Organelles Found in Both Animal and Plant Cells

1. The Nucleus--Controls the cell--Surrounded by a nuclear envelope/membrane

2. The Nucleolus--Site where DNA is concentrated within nucleus

3. Endoplasmic Reticulum

•Intracellular pathway moving molecules from one side of cell to the other.

3. Endoplasmic Reticulum •Has two parts•Moves supplies around cell

•Rough ER•Interconnected flattened sacs•Makes phospholipids and proteins•Studded with ribosomes•Many in protein producing cells (digestive gland)

•Smooth ER•Lacks ribosomes•Builds lipids (hormones)•Regulates calcium

FIGURE 4.10A

4. Golgi Apparatus

--flattened stacks of membranes

--Sorts, packages, labels, and modifies proteins and lipids from ER

--releases molecules in vesicles

5. Cytoskeleton

•Has many structures

•Network of tubes and filaments

•Gives the cell structure and supportEx: Cilia and Flagella (aid in movement)

6. Ribosomes

--Located on the rough ER and cytoplasm

--Site of protein synthesis

--Ribosomes are made by the nucleolus

7. Peroxisomes-- break down alcohol--neutralize free radicals

8. Vacuole-- mainly storage (water and sugar)

9. Mitochondria •converts sugar into cellular energy (ATP)•Contains its own DNA

--support for Endosymbiosis Theory--singular is "mitochondrion”--”power house” of the cell

FIGURE 4.17

Organelles Found ONLY in Plant Cells

10. Chloroplast

--Converts light energy to carbohydrates

--Has stacks of thylakoids

--has its own DNA

11. Central Vacuole --stores water, waste products, and nutrients

--maintains hydrostatic pressure

12. Cell Wall

•Lies outside the plasma membrane

•Contains cellulose

•Gives structure and support

Organelles Found ONLY in Animal Cells

13. Centrioles•Aid in cellular division •Two centrioles = centrosome

14. Lysosomes

--vesicles used to digest

--recycle old cell parts and kills bacteria

--contain degrading enzymes (to "lyse" means to dissolve)

TAY-SACHS disease – missing an enzyme of the lysosomes that breaks down a fatty substance. Over time this fat builds up in the brain and nervous tissue, smothering the cells. Results in degeneration and death.