1. Biology Unit 4 Notes #2 (Sections 3.2 – 3.4)
Cell Structure
Biology
Unit 4 Notes #2
(Sections 3.2 – 3.4)

2. Cell Types
With more advanced microscopes, scientists discovered that all cells can be grouped into two types:
prokaryotic cells
eukaryotic cells
Most prokaryotic cells are unicellular organisms (bacteria) called prokaryotes.
The genetic material in a prokaryotic cell is not surrounded by a membrane.

3. Cell Types
Plants, animals, fungi, and protists are all made of eukaryotic cells and are called eukaryotes.
In eukaryotic cells, the genetic material is surrounded by a membrane.
Every eukaryotic cell has membrane-surrounded organelles, which have specialized functions and enable the cell to carry out different functions at the same time.

4. Review – Cell Types Which category of cells contain nuclei?
How do prokaryotes and eukaryotes differ?

5. Basic Eukaryotic Cell Structure
All cells take in food, rid waste, reproduce
3 main sections
1) Cell membrane
2) Cytoplasm
3) Nucleus 3 2 1

6. CO2
water
1. Cell Membrane
Function: Controls the passage of materials into and out of a cell
Double layer of phospholipids (bilayer)
Semi-Permeable: only some materials may enter/exit
oxygen

7. 1. Cell Membrane 3 Parts Polar Head Nonpolar Tails
phosphate
Phospholipid Composition
3 Parts
Polar Head
1) Phosphate Group
2) Glycerol
Nonpolar Tails
3) Two chains of fatty
acids
Arrangement:
Outside: Polar heads
Inside: Nonpolar Tails
glycerol
Fatty acids

8. 1. Cell Membrane Phospholipid Bilayer “Water-loving”
“NOT Water-loving”

9. Review Name the 3 parts to a phospholipid?
Which part(s) make up the head of a phospholipid?
Which part(s) make up the tails of a phospholipid?
Which part of phospholipid always seems to be in contact with a watery environment? Why?

10. 2. Cytoplasm Jelly-like material inside of the cell
Most organelles float within
Nucleus
Ribosomes
Vacuoles
Mitochondria
Chloroplasts ER
Golgi Body
Lysosomes
Job: Help dissolve solutes & move materials around

11. 2. Cytoplasm
The cytoskeleton, is found within the cytoplasm maintains the shape of an animal cell.
The cytoskeleton is a network of threadlike proteins that are joined together.

12. 2. Cytoplasm
The cytoskeleton, maintains the shape of an animal cell.

13. 3. Nucleus
In most cells, the nucleus is the largest organelle. The nucleus is the part of a eukaryotic cell that directs cell activities and contains genetic information stored in DNA.
EM Research Services, Newcastle Unersity

14. 3. Nucleus
DNA in the nucleus is organized into structures called chromosomes.
The nucleolus is also contained in the nucleus and makes ribosomes, organelles involved in the production of proteins.
The nuclear envelope is a porous, two-membrane structure that surrounds the nucleus.

15. 3. Nucleus Job: Controls cell activity Inside: 1) Chromatin
long strands of DNA
holds info to make proteins
2) Nucleolus: makes ribosomes