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Eukaryotic: Cells with a Nucleus (plants & animals)

Prokaryotic: Cells without a Nucleus (bacteria)

Cell Membrane:  SURROUNDS ALL CELLS. A barrier between the environment and the inside of the cell. (F1)  The cell membrane also controls passage of materials in and out of the cell (F2)(similar to a window screen)

Cytoplasm: Fluid inside a cell, gel-like, between the cell membrane and the nucleus.  Where the organelles are located.

Organelles:Structures and chemicals in the cytoplasm, (not all the same).

These produce energy, build and transport needed materials and store & recycle waste. 

Nucleus: Control Center of the cell. The Brain

Surrounded by a membrane, nuclear membrane. Seperate from the cytoplasm. Contains the Chromatin, which is the genetic material (DNA & RNA) and the Nucleolus which makes ribosomes.

Endoplasmic Reticulum: (E.R.) Internal Delivery System

The E.R. carries lipids, proteins, and other material from one part of the cell to another. The formation is tubes and passageways (maze) for the material to go through. Located close to the nucleus The E.R. usually is bumpy due to having ribosomes attatched.

Ribososomes: Attatched to the E.R. The smallest organelle but the most abundant. They have no membrane. The job of the ribosomes is to collect amino acids from within the cell and make protein. The ribosomes are created inside the nucleus, as a nucleic acid.

Mitochondria: Powerhouse of the cell.

Produces most of the energy for the cell. It has two membranes. The internal membrane is made of many folds for greater surface area. This surface area is to enable more chemical reactions to occur (energy being released). Oxygen (element) is needed to perform chemical reactions.  Muscle and other active cells need more mithochondria cells for more ATP.

Golgi Complex: (Golgi Bodies)

Similar to the E.R. but transport proteins and other formed material from the E.R., package and distribute to other parts of the cell and outside.  Closer to the cell membrane. Pinches part off of itself to transport outside of the cell.

Chloroplasts: Plant cell and algae only. Two membranes, inside membrane is shaped as disks (stacked coins) to collect sunlight. The chloroplasts capture energy from sunlight and use it to produce food for the cell. (PHOTOSYNTHESIS) 

The chloroplasts also are green and give the color green to the plants.

Vacuoles: Storage Area

Contains water, food and other material. Also contains color and sour & sweet juices (lemon, orange). The size and the water help with support of the cell.  Most plant cells have one large vacuole. Some (few) animal cells have several small vacuoles. For our studies, we will say that it is only a plant organelle.

Cell Wall:  SURROUNDS PLANT CELLS ONLY. Protects and supports the plant, so it can grow tall. (F) It is made of cellulose, tough and flexible.

Lysosomes:Clean up Crew

Contains enzymes that break down large food particles, old cell parts and foreign invaders. Gets rid of waste. These are small, round organelles with a membrane to keep the chemicals inside. Usually in animal cells but sometimes found in plant cells. For our studies, we will say that it is only an animal organelle.


PASSIVE TRANSPORTATION: Movement of particles from a high concentration to a low concentration through proteins at the cell membrane.

No energy is needed.

Example: riding a bike down a hill

DIFFUSION: Movement of small particles (molecules) from a high concentration to a low concentration. When in a cell it is through proteins.

No energy is needed.

Example: air spray moving from close area to all around the room, or

bumper cars.

OSMOSIS: Diffusion of water from a high concentration to a low concentration through a selectively permeable membrane like the cell membrane. Pure water is the highest concentration. Pure water will always move to lower levels of concentration until the areas are of equal concentration.

No energy is needed.

Example: A glass of water of pure water and a wilted flower.

ACTIVE TRANSPORTATION: Diffusion of particles from a low concentration to a high concentration through a protein within the membrane. Movement of large molecules and minerals with the help of transport proteins; examples: calcium, potassium, and sodium.

Energy is required and used (ATP)

Example: riding a bike uphill

*Cells allow water and oxygen through the membrane. Other small particles must go through passive or active transportation.

* The cell membrane is selectively permeable so that some substances can pass through (A gatekeeper)

*Molecules are always moving and bump int each other.

ENDOCYTOSIS: The movement of large particles into the cell. The cell surrounds and encloses the particle within it. A vesicle is created to then transport the particle within the cell.

Example: Pac man

EXOCYTOSIS: Vessicles are formed to carry large particles to the cell membrane to leave the cell.

Example: Sweat

* Most energy comes from the sun

PHOTOSYNTHESIS: “made by light” Plants capture light energy and make food. 

We eat plants and other organisms that have eaten plants. 

Plants use the sun energy to change Carbod Dioxide and Water to food, in the form of glucose. Some of the food is stored and some is released with oxygen.

Plants are producers since they make their own food.

Organelle used: chloroplast

CO2 + H2O + Light = Glucose + O2

CELLULAR RESPIRATION: The break down of food that we eat to get the energy that our cells can use.  Oxygen is needed for the process to occur. The break down of foods gives us energy, some in the form of heat to keep our homeostasis.

Consumers use cellular respiration. This process is called aerobic.

Organelle used: mitochondria

Glucose + O2 = CO2 + H2O + Energy (ATP)

FERMENTATION:  Fermentation occurs in the animal and plant cells but in different ways. In animal cells, after the Oxygen supply is depleted or hard to get fermentation occurs. This process is the partial breakdown of glucose to get small amounts of ATP. This process is called anaerobic since it is without oxygen. The product we get is lactic acid and ATP.

Glucose = lactic acid + ATP