Chapter 7 Notes Cells
CELL FUNCTIONS:
1.
Digestion
2.
Absorption (ingestion)
3.
Biosynthesis- to make
4.
Respiration- using oxygen to change food into a usable form of energy
5.
Reproduction- cell division (fission)
6.
Excretion- getting rid of waste
7.
Secretion- passing out of materials produced by cells that are needed by other cells
8.
Response
9.
Transportation- movement of materials (ex. Food) inside a cell
10.
Growth
TWO TYPES OF CELLS:
Prokaryotes- “Pro” means before ;“Karyote” means nucleus has nuclear material no nuclear membrane to separate nuclear material from the rest of the cell few organelles, have ribosome’s bacteria and blue-green algae, Monerans
Eukaryotes- “Eu” means true nuclear material enclosed in a nuclear membrane many organelles, complex animal and plant cells (except blue-green algae), also protist and fungi
Prior learning: All cells belong to organisms in our ecosystem....the ecosystems is made up of producers and consumers- Chapter 3
Producer-organism that can make its own food (ex. Green plants)
Consumer- organism that cannot make its own food (ex. Animals)
HISTORY AND DEVELOPMENT OF THE CELL THEORY
1665- Robert Hooke (English)named cells he found in cork (dead cells)
1676- Anton van Leeuwenhoek (Dutch)observed and made drawings of small organisms found in tooth scrapings (called them animalcules) (living cells)
1824- R.J.H. Dutrochet (French)stated that all plant and animal tissues were made up of groups of cells. Explained that tissue growth was due to growth of individual cells.
1835- Felix Dujardin (French)-stated that single celled organisms were complete self sufficient living things.
1838- Mathias Schleiden (German)-all plants were made of cells
1839- Theodor Schwann(German)-all animals were made of cells
Schleiden and Shwann- proposed that cells were the basic units of structure and function in all living things.
1855- Rudolf Virchow (German)- all living cells come only from other living cells
1970- Lynn Margulis- proposed the idea that certain organelles, were once individual single-celled organisums themselves
CELL THEORY-
1) cells are the basic unit of structure and function of living things,
2) living cells are produced from other living cells
3) all living things are made up of cells
LEVELS OF ORGANIZATION

Cells are often organized to better serve the needs of the organism. The levels of organization in living things often begin at the microscopic level with organelles. Organelles working together form cells. Cells rarely work alone. Similar cells working together for a specific function are called tissues. Organs are groups of different tissues that work together. Organs work together and form specific systems. An organism is an entire living thing that carries out all of the basic life functions and is made of organ systems. The levels of organization from smallest to largest are:
Organelles----> Cells------> Tissues-----> Organs-----> Systems-----> Organisms
CELL ORGANELLES
1.Cell Wall
Found in plants cell (fungi, bacteria and some protest_ not in animal cells.
Nonliving outermost structure.
Hard, but allows H2O, O2, and CO2 and other dissolved materials to pass through.
Provides protection and support for plants cells.
Made of cellulose
Prior learning: cellulose is a complex polysacharride this is a carbohydrate made up of many monosacharrides -Chapter 2
2. Cell Membrane. (Plasma membrane)
Outermost structure in animal cells
Plant and bacteria cells also have – located just inside the cell wall.
Function – regulates movement of materials into and out of cell. The cell membrane allows a cell to maintain a stable internal environment as change occur in environment outside the cell (Homeostasis)
1) Permeable – allows substances to pass through.
2) Impermeable – prevents substances from passing through.
3) Selectively permeable – (Semi-permeable) allows some substances through while stopping other substances from
passing through the cell membrane
Prior learning: Phospholipid are types of lipids made up of a glycerol and three fatty acids (triglyceride)-
Chapter 2
3. Nucleus
Large oval or spherical structure
Made of proteins, enzymes, contain hereditary material
Function – control center of cell/direct all activities of cell.
Parts of nucleus
4. Nuclear membrane – regulates what enters and leaves membrane
5. Nucleoplasm – everything inside the nuclear membrane
6. Nucleolus – ribosorne RNA is made and stored here
7. Chromatin Material- Chromosomes; DNA
8. Cytoplasm
Clear thick protoplasm that fills the space between cell membrane and nucleus
Always moving
Organelles suspended in
9. Ribosomes
Site where proteins are made
Some float freely in cytoplasm and some are attached to Endoplasmic Reticulum

Endoplasmic Reticulum- E.R.
Canal-like membrane system in cytoplasm
10. Rough Endoplasmic Reticulum (contains ribosomes) – function is protein synthesis and transportation of proteins
11. Smooth Endoplasmic Reticulum (no ribosomes)- function is carbohydrate and lipid synthesis and transportation
12. Mitochondria
Oval, rod-shaped with inner membrane folds to increase production of ATP
Function- “Powerhouse of cell” ; cellular respiration
Supply energy for cell- break down food substances to to produce ATP..a chemical used for fuel by the cell
Vacuoles
13. Small Vacuoles
Found in plant and animal cells
Plant cells- larger and more numerous
Function- stores food, enzymes, water, other materials needed by cell
14. Large Central Vacuole
Large vacuole in plant cells that help cell maintain Turgor pressure (Osmotic pressure) the plant stores water in the large central vacuole. Not found in animal cells
*contractile vacuole is a vacuole that is found in some aquatic organisms in order to regulate osmosis
15. Lysosome
Small, round
Contain enzymes
Rare in plants- usually in cytoplasm of animal cells
Function- 1) Digestion 2) Destroy bacteria 3) Get rid of dead cells
16. Golgi Apparatus or Golgi Body
Closely stacked flattened sacs packages substances that the cell makes for use by the cell or to secrete to other cells
Plastids
Found in plant cells and some unicellular organisms
Function- 1) Make food 2) Store food 3) Give color
Types of Plastids
17. Leucoplast- Stores oils, starches, and protein (no color)
Chromoplast (catagory of plastids that contain pigment to give color) a major example is the chloroplast.
18. Chloroplast- a type of Chromoplast (makes plants green, photosynthesis, uses sunlight to convert low energy yeild reactants into high energy yeild products)
19. Microtubules- (part of the cytoskeleton) thin hollow cylinders made of protein; help animal cells to maintain shape- spindle fibers move chromosomes
20. Microfilaments- (part of the cytoskeleton) involved in changes in shape of cells
21. Centrioles- Found in animal cells; necessary for reproduction of cells- necessary for spindle fiber formation
Crossing The Membrane

Homeostasis–state of balance between cells and their environment
Diffusion– process by which molecules move from one place to another
Molecules diffuse from areas of greater concentration to areas of lesser concentration.(without energy)
Diffusion across cell membrane– some kinds of molecules can move between the molecules that make up the membrane.
Osmosis– diffusion of water through a membrane. Movement of water from a place of greater concentration to a place of lesser concentration. (without energy)
Passive Transport– movement of molecules across a membrane without the use of chemical energy.
Facilitated diffusion (such as ion channels and glucose permease), and Osmosis are examples of passive transport
Osmotic Pressure-pressure that builds up during osmosis as water enters the cell and forces the cytoplasm against the cell membrane. In plants the build up of osmotic pressure is calledTurgor
Pressure.
Active Transport
Requires energy (ATP)
Lesser concentration of molecules to a greater one
Against the gradient
1. Endocytosis
2. Exocytosis
3. Sodium Potassium pump
Passive Transport
No energy required
Greater concentration of molecules to lesser concentration of molecules
With the gradient
1. Diffusion
2. Facilitated Transport (Ion Channel)
3. Osmosis
Hypotonic solution is a healthy for a plant cell, because they build up turgor pressure
Isotonic solution is healthy for an animal cell, because its just the right amount of osmotic pressure for normal cell.
Hypertonic solutions are unhealthy for both plant and animal cell because they lose all their osmotic pressure.
Prior learning;
Solution is made up of a Solvent- (a liquid that a solute is dissolved in ex; water) and aSolute-( the substance that dissolves in a solvent ex: Sugar) Chapter 2