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Robert Hooke

In 1665, Robert Hooke (born in 1635 in England) was looking at empty cork cells under a microscope and named them.

The Cell Theory

1. All living things are made up of cells. They are the basic unit of life.
2. All cells come from other living cells.

Parts of a Microscope and Functions

Ocular lens: The eyepiece, to be looked through. Magnifies 10x.
Nosepiece: Holds the objective lenses, can be rotated to change them.
Objective lenses: The main magnification. There are three levels of magnification: 4x, 10x, and 40x.
Stage clips: Hold the slide in place.
Stage: Where the slide is put and where the light comes through.
Light: Provides light to see the specimen.
Arm: Supports the microscope and hols the ocular lens and nosepiece.
Coarse focus: Moves the stage up and down to focus the image.
Fine focus: Moves the stage slightly to get detailed focus.
Diaphragm: Controls how much light is let through to the specimen.
Base: the bottom of the microscope. Also supports the microscope.

Resolution

The ability of a lens system to show fine details of the object being observed.

Field of View

The diameter of the circle of light that is seen when looking into a microscope. The higher the magnification, the smaller the field of view. Sometimes it is abbreviated to FOV.

Depth of Field

It is possible to see varying levels of the specimen when it is being magnified. The higher the magnification, the more levels can be seen.

Micrometer

Also called a micron, it is used in microscopy. There are 1,000 micrometers in a millimeter.

Prokaryotic Cells

Contain no true nucleus or complex organisms (bacteria).

Eukaryotic Cells

Contain a nucleus surrounded by a membrane (all living cells except bacteria)

Parts of an Animal Cell and Functions

Nucleus: Contains the DNA (in chromosomes) that makes the cell unique. It also controls the functions of the organelles.
Nucleolus: The prominent structure in the nucleus, the nucleolus produces ribosomes, which are necessary of protein synthesis.
Mitochondria: Provides cell with energy by cellular respiration (combining glucose (food) with oxygen to create fuel and energy). They also burn carbohydrates and glucose tomake energy
Rough Endoplasmic Reticulum (RER): An endoplasmic reticulum is a network of membrane-bound tubes and vesicles. RERs appear rough because of the numerous ribosomes on them. RERs store and transport proteins from the ribosomes.
SER: An endoplasmic reticulum is a network of membrane-bound tubes and vesicles. SERs appear smooth and make lipids (fats).
Ribosomes: Packets of RNA and protein that synthesizes protein (lengthening the protein chain).
Cytoskeleton: Mantains the cell's shape and helps it move.
Cytosol/Cytoplasm: A gel/liquid substance that fills the inside of the cell. It is mostly water with some proteins, and is where all the organelles reside. Cytoplasm is the cytosol and all the organelles.
Golgi apparatus: A stack of membrane-bound vesicles important for packaging micro-molecules to transport elsewhere in the cell.
Lysosomes: Contain an enzyme (hydrolytic enzyme) necessary for intracellular digestion.
Secretory vesicle: Where cell secretions are stored and transported.
Vacuole: A membrane-bound sac that stores water food and waste. It also helps in intracellular digestion and the release of waster products.
Cell membrane: Controls the flow of water and other substances in and out of the cell. It is made of two layers of phospholipids with protein embedded.
Nuclear membrane: A two-layer membrane that surrounds the nucleus and controls what goes into it and comes out.
Centrioles: Involved in cell division.
Peroxisomes: Protect the cell from hydrogen peroxide, which they produce. It is toxic to the cell. Peroxisomes also break down poisons.
Chromosomes (chromatin): Contains DNA and protein (genes) and provides instructions for the cell.

Parts of a Plant Cell and Functions

Nucleus: Contains the DNA (in chromosomes) that makes the cell unique. It also controls the functions of the organelles.
Nucleolus: The prominent structure in the nucleus, the nucleolus produces ribosomes, which are necessary of protein synthesis.
Mitochondria: Provides cell with energy by cellular respiration (combining glucose (food) with oxygen to create fuel and energy). They also burn carbohydrates and glucose to make energy
Rough Endoplasmic Reticulum (RER): An endoplasmic reticulum is a network of membrane-bound tubes and vesicles. RERs appear rough because of the numerous ribosomes on them. RERs store and transport proteins from the ribosomes.
SER: An endoplasmic reticulum is a network of membrane-bound tubes and vesicles. SERs appear smooth and make lipids (fats).
Ribosomes: Packets of RNA and protein that synthesizes protein (lengthening the protein chain).
Cytoskeleton: Mantains the cell's shape and helps it move.
Cytosol/Cytoplasm: A gel/liquid substance that fills the inside of the cell. It is mostly water with some proteins, and is where all the organelles reside. Cytoplasm is the cytosol and all the organelles.
Golgi apparatus: A stack of membrane-bound vesicles important for packaging micro-molecules to transport elsewhere in the cell.
Lysosomes: Contain an enzyme (hydrolytic enzyme) necessary for intracellular digestion.
Secretory vesicle: Where cell secretions are stored and transported.
Vacuole: A membrane-bound sac that stores water food and waste. It also helps in intracellular digestion and the release of waster products. It keeps the cell from wilting, and is very large.
Cell membrane: Controls the flow of water and other substances in and out of the cell. It is made of two layers of phospholipids with protein embedded.
Nuclear membrane: A two-layer membrane that surrounds the nucleus and controls what goes into it and comes out.
Peroxisomes: Protect the cell from hydrogen peroxide, which they produce. It is toxic to the cell. Peroxisomes also break down poisons.
Chromosomes (chromatin): Contains DNA and protein (genes) and provides instructions for the cell.
Chloroplasts: Contains chlorophyll, which is responsible for the cell's green color. Also, photosynthesis occurs here, producing food (glucose).
Cell wall: Maintains the shape of the cells and is a protective barrier. It is made of cellulose.

Differences Between Plant and Animal Cells

Plant cells have cell walls, larger vacuoles, and chloroplasts. Animal cells have centrioles and smaller vacuoles. Everything else is the same.

Diffusion

The movement of molecules across a cell membrane from an area of higher concentration to an area of lower concentration, in order to reach equilibrium.

Osmosis

he movement of water molecules (or another solvent) through diffusion.

Active Transport

The passage of molecules moving from one side of a membrane to another by means of the cell's energy.

Passive Transport

The movement of molecules across a cell membrane by diffusion.

The Egg Lab

The egg lab was a lab where osmosis was observed with an egg. It was put in different solutions, then was left to see which way osmosis would occur.

Semipermeable

Only some molecules can get through (like water).

Hypotonic

A solution with less solute than solvent.

Hypertonic

A solution with more solute then solvent.

Isotonic

A solution with equal amounts of solute and solvent.

Turgor Pressure

A cell's pressure from the cell's contents against the plasma membrane.

Plasmolysis

The shrinking of a cell due to loss of water by osmosis.

Cytolysis

The destruction of a cell.

Interphase

The stage of the cell cycle when the cell is growing, engaged in metabolic activity, carrying out its normal functions. The DNA replicates (makes a copy of itself) at the end of this phase.

Prophase

Chromosomes begin to condense and become visible as two chromatids connected by a centromere. Nuclear membrane is disappearing. Spindle fibers begin to form.

Metaphase

Sister chromatids line up at the middle of the cell (equatorial plate). They are attached to spindle fibers, which help get them in place.

Anaphase

The sister chromatids separate at the centromere and pull apart, bringing identical DNA to each side of the cell

Telophase

Two nuclei begin to form around the new bundles of chromosomes. A cleavage furrow (a pinching in of the membrane) forms in animal cells and a cell plate (new cell wall) forms in plant cells. In animal cells, the cleavage furrow pinches in until the cells separate into two daughter cells.

Why Is Mitosis Important?

Mitosis is important because it replaces cells that die and makes skin and organs able to repair themselves, It is important for single-celled organisms because it keeps then from dying and then going extinct.

Homeostasis

The balance of a system.

Solution

A mixture of two dissolved substances.

Solvent

The substance (liquid) that is used to dissolve solutes.

Solute

The substance that is dissolved in a solution.

Osmotic Equilibrium

When the solutions on both sides of a membrane are isotonic.

Cell Membrane

It controls the flow of water and other substances in and out of the cell. It is made of two layers of phospholipids with protein embedded.

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