1. Eukaryotic Cell Structures
All About Cells
Eukaryotic Cell Structures

2. The Basics of a Cell
Much like our bodies are made up of organs, cells are made up of smaller parts called organelles.
Eukaryotic cells are divided into two major parts:
The nucleus
The cytoplasm – the portion of the cell outside the nucleus

3. The Nucleus The nucleus: Is the control center of the cell
Contains almost all of the cell’s DNA
The nucleus contains codes that allows it to make proteins and other important molecules

4. The Parts of the Nucleus
Nuclear envelope – the two membrane structure that surrounds the nucleus
Nuclear pores – pores on the surface of the nuclear envelope that allow material to move in and out of the nucleus
Chromatin – consists of DNA bound to protein, and is spread throughout the nucleus; when the cell divides the chromatin condenses to form Chromosomes.
Chromosomes – contain the genetic material that is passed from one generation to the next.
Nucleolus – where the assembly of ribosomes begins

5. Ribosomes
Ribosomes are small particles of RNA and protein found throughout the cytoplasm
They produce proteins by following the instructions of the nucleus
Can be found:
Attached to membranes of cell organelles
Free floating

6. Endoplasmic Reticulum
The site of where lipid components of the cell membrane are assembled, along with proteins and other materials that are exported from the cell

7. Types of Endoplasmic Reticulum
There are two types of Endoplasmic Reticulum, or ER:
Rough ER – which is involved in the synthesis of proteins
Called rough ER because of the ribosomes found on its surface
Smooth ER – in many cells, contains enzymes that perform specialized tasks, including the synthesis of membrane lipids and the detoxification of drugs
Called smooth ER because of the lack of ribosomes found on its surface

8. Golgi Apparatus
Proteins produced in the Rough ER move into the Golgi Apparatus
The function of the Golgi Apparatus is to modify, sort, and package proteins and other materials from the ER for storage in the cell or secretion outside the cell

9. Lysosomes Filled with enzymes
One function is the digestion, or breakdown, of:
Lipids
Carbohydrates
Proteins
This allows the rest of the cell to use this fuel
They also function to breakdown other organelles that have reached the end of their usefulness

10. Vacuoles Storage in the cell Store materials such as: Water Salts
Proteins
Carbohydrates
In many plants, there is a single fluid filled vacuole
This feature in plants make is possible for them to support heavy structure such as leaves and flowers
Also can be found in some animals and unicellular organisms

11. Mitochondria
Organelles that convert the chemical energy stores in food into compounds that are move convenient for the cell to use
Considered the “power house” of the cell
Enclosed by two membranes; the inner membrane is folded up
Your mitochondria is inherited from your mother!

12. Chloroplasts
Organelles that capture energy from sunlight and convert it into chemical energy in a process called photosynthesis
The biological equivalent to a solar power plant
Surrounded by two membranes
Inside the organelle are stacks of other membranes with contain the green pigment chlorophyll

13. Cytoskeleton
Supporting structure and transportation system in the cell
A network of protein filaments that helps the cell to maintain its shape
Also involved in movement
Two principle proteins filaments make up the cytoskeleton:
Microfilaments
Microtubules

14. Microfilaments Threadlike structures made of a protein called ACTIN
Form an extensive network in some cells and produce a tough, flexible framework that supports the cell
Also can help the cell move

15. Microfilaments
In animal cells, structures known as centrioles are formed from tubulin
Centrioles:
Are located near the nucleus
Help aid in cellular division

16. Microfilaments
Microtubules also help to build projections from the cell surface that enable cells to swim rapidly through liquids
These projections are:
Cilia/Cilium
Flagella/Flagellum

17. Microtubules Hollow structures made up of proteins known as TUBULINS
Play critical roles in maintaining cell shape
Also important in cell division – they help separate the chromosomes

18. Analogies
A comparison between two different things in order to highlight some point of similarity
For example: science writer Claudia Kalb relies on the computer to explain how our brains process memories:
Some basic facts about memory are clear. Your short-term memory is like the RAM on a computer: it records the information in front of you right now. Some of what you experience seems to evaporate--like words that go missing when you turn off your computer without hitting SAVE. But other short-term memories go through a molecular process called consolidation: they're downloaded onto the hard drive. These long-term memories, filled with past loves and losses and fears, stay dormant until you call them up. ("To Pluck a Rooted Sorrow," Newsweek, April 27, 2009)

19. The Cell As A Factory
Membrane – the walls, floor and roof of the factory
Cytoplasm – the air in the factory
Nucleus– the main office in a factory
Ribosomes – small machines, turning out proteins on the orders of its ‘boss” – the nucleus

20. The Cell As A Factory Endoplasmic Reticulum:
Rough ER - Assembly line, gets proteins from the ribosomes and modifies them
Smooth ER – Specially trained workers
Golgi Apparatus – Customization shop, putting the finishing touches on proteins and readying them for shipment, then ships the proteins to the parts of the cell where they are needed
Lysosomes – the cleanup crew of the factory

21. The Cell As A Factory Vacuoles – the storage room
Mitochondria – the powerhouse of the factory, converting one form of energy into another
Chloroplasts – solar power plants, providing energy to the factory
Cytoskeleton – the steel or cement beams and columns that provide the factory’s structure