1. Cell Structure and Function

2. The Discovery of the Cell
Robert Hooke – first to see and identify cork “cells” using a microscope.
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3. The Cell Theory Cell Theory:
All living things are made of one or more cells.
Cells are the smallest unit of life.
New cells are produced from pre-existing cells.
Schleiden
Schwann
Virchow
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4. Basic Cell Substances The main ingredient of any cell is water.
The structure of a water molecule makes it ideal for dissolving many other substances

5. Macromolecules Macromolecules form when many small molecules join
The 4 types of macromolecules are:
Nucleic acids-
form when long chains of nucleotides join.
Important because they contain genetic information
Ex: DNA and RNA

6. Macromolecules 4. Proteins- Necessary for nearly everything cells do
Made up of long chains of molecules called amino acids.
Some help break down nutrient in food
3. Lipids-
large molecule that does not dissolve in water
Store energy
Plays an important role as protective barriers in cells (membranes)

7. Macromolecules 4. Carbohydrates-
Made up of one or more sugar molecules
Store energy
Provide structural support
Used for communication between cells

8. Prokaryotes and Eukaryotes
Cells can be grouped into 2 types:
Prokaryotes – cells that do not contain nuclei.
Ex: (Bacteria)
Eukaryotes – cells that contain nuclei and have membrane-surrounded components called organelles which have specialized functions
Ex: plants, animals, fungi, protist

9. Eukaryotic Cell Structure
Organelles – structures in a cell that act like “little organs.”
Cytoplasm – the jelly-like fluid where the organelles “float.”
It contains salts and other molecules

10. The Nucleus
Nucleus – large membrane-enclosed structure that contains the cell’s genetic information and directs cell activities
Nuclear Envelope – membrane that surrounds the nucleus.
Nuclear Envelope

11. Mitochondria
Mitochondria – converts chemical energy stored in food into energy(ATP).
“Powerhouse of the Cell!”
Converts glucose and oxygen into ATP, Carbon Dioxide (CO2) and Water (Cellular Respiration)
ATP- the fuel for cellular processes such as growth, cell division, and material transport

12. Mitochondria
Mitochondria

13. Ribosomes Ribosomes – Make Proteins!
Found in a cells cytoplasm or attached to the endoplasmic reticulum (E.R)
Ribosome

14. Endoplasmic Reticulum (ER)
Endoplasmic reticulum –transports proteins to the Golgi apparatus and breaks down toxic material.
Rough ER – has ribosomes
Smooth ER – no ribosomes

15. Endoplasmic Reticulum (ER)
Rough ER
Smooth ER

16. Golgi Apparatus
Golgi Apparatus (Golgi bodies)- prepares proteins and packages them into ball-like structures called vesicles
Golgi Apparatus

17. Lysosomes
Lysosomes – small organelles filled with enzymes that help recycle cellular components

18. Vacuoles Vacuoles – store food, water, and waste material
Animal cells have small vacuoles
Plant cells have large Central Vacuoles
Vacuoles

19. Chloroplasts
Chloroplasts – organelles that capture energy from sunlight and convert it into chemical energy. (Photosynthesis)
Found only in plants.
Chloroplast

20. Cytoskeleton
Cytoskeleton – made of a network of threadlike proteins that are jointed to form a framework inside a cell.
helps cell to maintain shape, move, and move organelles.

21. Cell Boundaries
Cell membrane – thin, flexible membrane that surrounds the cell and protects the inside of a cell from the environment outside.
Controls what enters and leaves the cell.
Made of phospholipids (2 layers) and proteins.
Two layers!

22. Cell Boundaries
Cell wall – rigid layer around the membrane that provides structure and support.
found only in bacteria, fungi and plants.

23. Cell Appendages Cell appendages are often used for movement.
Flagella- long, tail- like appendage that whip back and forth and move a cell.
Cilia- short hair like structures that can move a cell or move molecules away from a cell.

24. Moving Cellular Material

25. The exchange of materials between as cell and its environment takes place at the cell membrane.
A cell membrane is semipermeable- it allows only certain substance to enter or leave a cell

26. Passive Transport
Passive transport – the movement of substances through a cell membrane without using the cell’s energy
Diffusion – movement of particles from an area of high to low concentration.
Diffusion continues until the concentration of a substance is the same on both sides of a membrane.
Osmosis – the diffusion of water through a membrane.

27. Osmosis Practice 90% H2O 10% NaCl
Cell
Concentrations are equal, so no net movement of water!
90% H2O
10% NaCl
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28. Osmosis Practice 80% H2O 20% NaCl
Cell
Concentration of water is greater in the cell than out, so water will move out!
90% H2O
10% NaCl

29. Osmosis Practice 90% H2O 10% NaCl
Cell
Concentration of water is greater outside the cell than
in, so water will move
In!
80% H2O
20% NaCl
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30. Active Transport
2. Active Transport- The movement of materials across a cell membrane with the use of energy
Moves substances from areas of low concentration to areas oh high concentration
Exocytosis – a cell’s vesicles releases their contents outside of the cell.
Endocytosis – the cell surrounds a large particle and brings it into the cell

31. Cell Size and Transport
For a cell to survive, its surface area must be large compared to its volume.
As a cell grows, its volume increases faster than its surface area

32. Cells & Energy

33. CELLULAR RESPIRATION All living things need energy to survive
Cellular Respiration – converts the energy in food molecules into a usable form of energy called ATP

34. CELLULAR RESPIRATION
Step 1: Glycolysis- occurs in the cytoplasm of all cells
Glucose is broken down into smaller molecules
Step 2: Occurs in the mitochondria of Eukaryotic cells and requires oxygen
Small molecules made during glycolysis are broken down
Large amounts of usable energy called ATP are produced
Water and Carbon Dioxide is given off

35. CELLULAR RESPIRATION
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36. FERMENTATION C6H1206 ATP + Lactic Acid C6H1206 ATP + Alcohol + CO2
Eukaryotic and prokaryotic cells use fermentation to obtain energy from foods when oxygen levels are low.
It occurs in the cell’s cytoplasm
Lactic- acid fermentation- Occurs in muscles
C6H ATP + Lactic Acid
(Glucose) (energy)
Some types of bacteria and yeasts make ATP during alcohol fermentation.
C6H ATP + Alcohol + CO2
(Glucose) (energy)

37. PHOTOSYNTHESIS
Plants and some unicellular organisms obtain energy from light (radiant energy)
Photosynthesis is a series of chemical reactions that converts light energy into chemical energy (Glucose)

38. PHOTOSYNTHESIS
In plants light energy is absorbed by pigments called chlorophyll
Photosynthesis occurs in the chloroplasts
Uses CO2 that is released during cellular respiration to make food energy and release oxygen.