Mrs. Wetzel Biology Chapter 3 Power Point

Cell Theory Early Discoveries: Almost all cells are too small to be seen with the naked eye. Prior to the discovery of the Microscope cells were unheard of. The Dutch Eyeglass maker Zacharias Janssen and his father Hans. Get credit for making the first known Microscope.

Scientists who contributed to the Cell Theory

Cork Cells What part of the cells was Robert Hooke seeing when he examined the cork?

Scientists who contributed to the Cell Theory

Cell Theory * All living things are made of cells *All cells come from other living cells *The cell is the most basic unit of life. There is nothing living that is smaller than a cell

Cell Theory * All living things are made of cells *All cells come from other living cells *The cell is the most basic unit of life. There is nothing living that is smaller than a cell

Two types of Cells Cells come in many different shapes and carry out many different jobs. However they all share some features. 1. Cells are all SMALL 2. Cells all have a membrane of some sort to keep materials in or out 3. Cells have cytoplasm on the inside 4. Cells have genetic material Cells come in many different shapes and carry out many different jobs. However they all share some features. 1. Cells are all SMALL 2. Cells all have a membrane of some sort to keep materials in or out 3. Cells have cytoplasm on the inside 4. Cells have genetic material

Two types of Cells; Prokaryotic & Eukaryotic Prokaryotic: Prokaryotic Cells are VERY small. Their DNA floats in the cytoplasm They have no Nucleus They have no distinct Membrane Bound Organelles Prokaryotic: Prokaryotic Cells are VERY small. Their DNA floats in the cytoplasm They have no Nucleus They have no distinct Membrane Bound Organelles

Two types of Cells Eukaryotic: Are larger than Prokaryotic Cells They have a nucleus DNA (genetic material) Lives in the Nucleus They have Membrane bound Organelles Some are unicellular, some are multicellular

Two types of Cells EukaryoticProkaryotic

Two types of Cells Eukaryotic *Larger *Nucleus *Membrane Bound Organelles Prokaryotic *Smaller *No Nucleus * No Membrane Bound Organelles

Two types of Cells Eukaryotic *Larger *Nucleus *Membrane Bound Organelles FOUND IN : PROTISTA, FUNGI, PLANTS, & ANIMALS Prokaryotic *Smaller *No Nucleus * No Membrane Bound Organelles FOUND ONLY IN: BACTERIA

Relevancy Check What Kingdoms have Eukaryotic Cells, Which ones have Prokaryotic? Prokaryotic Eukaryotic What Kingdoms have Eukaryotic Cells, Which ones have Prokaryotic? Prokaryotic Eukaryotic

Cell Structures Cytoskeleton: Your Skeleton is made of bones that help keep all of your body parts in place. Eukaryotic Cells have a skeleton too. The CYTOSKELETON is the framework for the cell Cytoskeleton: Your Skeleton is made of bones that help keep all of your body parts in place. Eukaryotic Cells have a skeleton too. The CYTOSKELETON is the framework for the cell

Cytoskeleton Three Parts of the cytoskeleton are: Microtubules-Movement Microfilaments-Cell Division & movement Intermediate filaments- Cell strength

Cell Structures Nucleus: Stores and Protects the DNA of the Cell DNA contains genetic material and instructions for making proteins It is often called the brain of the cell Nucleus: Stores and Protects the DNA of the Cell DNA contains genetic material and instructions for making proteins It is often called the brain of the cell

Cell Structures Endoplasmic Reticulum: A network of folded membranes that helps in the production of proteins. Looks like a maze Endoplasmic Reticulum: A network of folded membranes that helps in the production of proteins. Looks like a maze

Cell Structures Ribosomes: Tiny organelles that link amino acids together to form proteins. They are found on the ER, or floating in the cytoplasm Ribosomes: Tiny organelles that link amino acids together to form proteins. They are found on the ER, or floating in the cytoplasm

Ribosomes

Golgi Apparatus: Packages proteins for transport within the cell, or to destinations outside of the cell

Cell Structures Vesicles: Are small sacs that carry different molecules to where they are needed.

Cell Structures Mitochondrion: Supplies Energy for the cell Bean shaped Inner Membranes with many folds and compartments Converts food you eat into usable energy Mitochondrion: Supplies Energy for the cell Bean shaped Inner Membranes with many folds and compartments Converts food you eat into usable energy

Cell Structures Vacuole: A fluid Filled sac used for the storage of materials needed by the cell Water, nutrients, etc. ANIMAL CELLS- Small vacuoles PLANT CELLS- LARGE Vacuole Vacuole: A fluid Filled sac used for the storage of materials needed by the cell Water, nutrients, etc. ANIMAL CELLS- Small vacuoles PLANT CELLS- LARGE Vacuole

Cell Structures Lysosome: Organelles that contain enzymes Protect a cell by attacking incoming bacteria and viruses Breaks down old cell parts Lysosome: Organelles that contain enzymes Protect a cell by attacking incoming bacteria and viruses Breaks down old cell parts

Cell Structures Centriole: Shaped like tiny tubes in a circle Help animal cells divide Centriole: Shaped like tiny tubes in a circle Help animal cells divide

Plant Cells Vs. Animal Cells Plant CellAnimal Cell Cell Wall Large Vacuole Chloroplasts Cell Wall Large Vacuole Chloroplasts Centrioles Lysosomes Centrioles Lysosomes

Plant Cells Vs. Animal Cells Plant CellAnimal Cell

Plant Cells Vs. Animal Cells Plant Cell WallAnimal Cell Membrane Cell Wall; Strong, rigid, layer that protects, supports, and shapes the cell. Some cell walls are very thick Cell Membrane; a thin layer that separates the inside of the cell from the outside. It is selectively permeable.

Cell Wall vs. Cell Membrane Cell WallCell Membrane

Phospholipid Bilayer- Provides a selectively permeable protective covering for cells Allows some materials to pass through, some can not The cell membrane is referred to as a fluid mosaic model because the phospholipids are not rigid, they can move and slide

Cell Membrane Phospholipid Charged Phosphate group Glycerol 2 Fatty acid chains

Cell Membrane A variety of Molecules are embedded among the phospholipids. Cholesterol: Molecules strengthen the cell membrane Proteins: Channels that extend through the membrane helping materials to cross over Carbohydrates: act as identification. Allowing the cell to communicate with each other

Selective Permeability A selectively permeable membrane allows some, but not all molecules to cross.

Relevancy Check: What can you think of that has a selectively permeable membrane?

Concentration Gradient Concentration is the amount molecules of one type in an area. Few Molecules= Low concentration Lots of Molecules= High concentration. Concentration of molecules can vary from one area to another. A Concentration Gradient is the difference in the concentration of a substance from one location to another. Concentration is the amount molecules of one type in an area. Few Molecules= Low concentration Lots of Molecules= High concentration. Concentration of molecules can vary from one area to another. A Concentration Gradient is the difference in the concentration of a substance from one location to another.

Relevancy Check What in your daily life reminds you of a concentration gradient?

Movement across the Cell Membrane Ways molecules can move across the cell membrane (enter or leave a cell) 1. Passive Transport A. Diffusion: The movement of molecules from an area of High concentration to an area of Low concentration (no energy needed) B. Osmosis: The movement of WATER molecules from an area of high concentration to low concentration C. Facilitated diffusion: gets help from protein channels embedded in cell membrane Ways molecules can move across the cell membrane (enter or leave a cell) 1. Passive Transport A. Diffusion: The movement of molecules from an area of High concentration to an area of Low concentration (no energy needed) B. Osmosis: The movement of WATER molecules from an area of high concentration to low concentration C. Facilitated diffusion: gets help from protein channels embedded in cell membrane

Movement across the Cell Membrane Ways molecules can move across the cell membrane (enter or leave a cell) 1. Active Transport: Requires energy from the cell. Molecules move across the concentration gradient. From an area of low concentration to High concentration. A. Endocytosis- takes in large molecules of oPhagocytosis is a type of endocytosis that “Eats” large molecules B. Exocytosis – opposite of endocytosis- large molecules exit the cell Ways molecules can move across the cell membrane (enter or leave a cell) 1. Active Transport: Requires energy from the cell. Molecules move across the concentration gradient. From an area of low concentration to High concentration. A. Endocytosis- takes in large molecules of oPhagocytosis is a type of endocytosis that “Eats” large molecules B. Exocytosis – opposite of endocytosis- large molecules exit the cell

Facilitated Diffusion vs. Simple Diffusion Facilitated diffusion relies on Protein Channels to transfer larger ions across the cell membrane. It requires no energy from the cell because the molecule go from an area of high concentration to an area of low concentration.

Osmosis Osmosis The movement of water across a semi permeable membrane. Osmosis is the movement of water (red dots) through a semipermeable membrane to a higher concentration of solutes (blue dots).

Isotonic Isotonic Solution A solution that has the same salt concentration as the normal cells of the body and the blood. When a cell is placed in an isotonic solution, the water diffuses into and out of the cell at the same rate. The fluid that surrounds the body cells is isotonic

Hypertonic Hypertonic Solution A Hypertonic solution contain a high concentration of solute in relation to the solution within the cell (e.g. the cell's cytoplasm). When a cell is placed in a hypertonic solution, the water diffuses out of the cell, causing the cell to shrivel up.

Hypotonic Hypotonic Solution A hypotonic solution contain A solution with a lower salt concentration than in normal cells When a cell is placed in a hypotonic solution, the water diffuses into the cell, causing the cell to swell and possibly explode.

Active Transport Active Transport Active Transport requires the cell to use energy, usually in the form of ATP. Active Transport creates a charge gradient in the cell membrane. For example in the mitochondrion, hydrogen ion pumps pump hydrogen ions into the intermembrane space of the organelle as part of making ATP. Active Transport Active Transport requires the cell to use energy, usually in the form of ATP. Active Transport creates a charge gradient in the cell membrane. For example in the mitochondrion, hydrogen ion pumps pump hydrogen ions into the intermembrane space of the organelle as part of making ATP.

Endocytosis ENDOCYTOSIS Endocytosis (Endo (within) cytosis (cell) ) is a process in which a substance (e.g. proteins) gains entry into a cell without passing through the cell membrane. ENDOCYTOSIS Endocytosis (Endo (within) cytosis (cell) ) is a process in which a substance (e.g. proteins) gains entry into a cell without passing through the cell membrane.

Phagocytosis

Exocytosis EXOCYTOSIS Endocytosis (Exo (exit) cytosis (cell) ) is a process in which a substance is exited from the cell without passing through the cell membrane. Examples of things that might be exited include secretion of proteins like enzymes, hormones and antibodies EXOCYTOSIS Endocytosis (Exo (exit) cytosis (cell) ) is a process in which a substance is exited from the cell without passing through the cell membrane. Examples of things that might be exited include secretion of proteins like enzymes, hormones and antibodies