Chapter 7 Cell Structure and Function Juan Herrera Biology Period 2

7.1 Life is Cellular SC.912.L.14.1 The Discovery of the Cell What is the cell theory? We will not be able to see cells with out the microscope All living things are made up of cells Cells are the basic units of structure and function in living things New cells are produced from existing cells. Microscope Plant Cell

7.1 Life is Cellular SC.912.L.14.1 Early Microscopes The first proto-microscope was used in 1665 Cell are not chambers they actually have a huge array of working parts. Anton van Leeuwenhoek discovered that cells are everywhere. Leeuwenhoek was the first to discover the bacteria in the human mouth. Anton Van Leeuwenhoek

7.1 Life is Cellular SC.912.L.14.1 The Cell Theory Cells are the basic unit of life. Cells can only be formed from pre-existing cells. Cell theory: All living things are made up of cells Cells are the basic units of structure and function in living things New cells are produced from existing cells.

7.1 Life is Cellular SC.912.L.14.1 Exploring the cell How do microscopes work? Microscopes produce an enlarged image of something very small. Most microscopes use lenses to magnify the image of an object by focusing light or electrons.

7.1 Life is Cellular SC.912.L.14.1 Exploring the cell? Microscopes are still used to day to explore the cell Scientist today use really powerfully microscopes.

7.1 Life is Cellular SC.912.L.14.1 Light Microscopes and Cell Stains The most common type of microscope is the compound light microscope. The objects get magnifying it 1000 times Dyes are used to solve the transparency problem with most living cells.

7.1 Life is Cellular SC.912.L.14.1 Electron Microscopes It is used in to see cells and cell structures as small as 1 millionth of a meter. Electron microscopes can be used to get a higher resolution than other microscopes. 2 types of electron microscopes transmission and scanning. Electron can easily be moved by the air, which mean samples much be placed in a vacuum.

7.1 Life is Cellular SC.912.L.14.1 Prokaryotes and Eukaryotes Cell membrane: Semipermeable barrier that is flexible and protects the cell. Nucleus: is a large membrane enclosed structure that contains genetic material in the form of DNA. Eukaryotes are cells that enclose their DNA in nuclei Prokaryotes are Cells that do not enclose DNA in nuclei.

7.2 Cell Structure SC.912.L.14.3 Cell Organization What is the role of the cell nucleus? Cytoplasm is a portion of the cell outside the nucleus. Organelles structures that act like specialized organs. Nucleus contains nearly the cell’s DNA the coded instruction for proteins and other important molecules.

7.2 Cell Structure SC.912.L.14.3 Comparing the cell to a factory? The cell is like a living factory The different organelles are compared to specialized machines.

7.2 Cell Structure SC.912.L.14.3 Nucleus Nucleus contains nearly the cell’s DNA the coded instruction for proteins and other important molecules. Nucleus has 4 main parts: Nuclear pores, Chromatin, Nucleolus, Nuclear envelope. Chromosomes carry the cell genetic information The brain of the cell

7.2 Cell Structure SC.912.L.14.3 Organelles that Store, Clean up, and Support What are the functions of vacuoles, lysosomes and the cytoskeleton? Vacuoles store, Lysosomes Clean up, and Cytoskeleton support. These organelles are the storage space, Clean up crew, and support structures.

7.2 Cell Structure SC.912.L.14.3 Vacuoles and Vesicles? Vacuoles store materials like water, salts, proteins and carbohydrates. Many plants have a central vacuole. If Vacuoles did not exist then the cell would not be able to store materials that it needs to survive.

7.2 Cell Structure SC.912.L.14.3 Lysosome

7.2 Cell Structure SC.912.L.14.3 Lysosomes Lysosomes are small organelles filled with enzymes. Lysosomes break down lipids, carbohydrates, and proteins into small molecules that can be used by the rest of the cell. They are also involved in breaking down organelles that have outlived their usefulness. A lot of human diseases are formed by function failed in the lysosomes.

7.2 Cell Structure SC.912.L.14.3 The Cytoskeleton Shapes the cell’s internal organization by a network of protein filaments. It involves in movement. There are 2 principle protein filaments Microfilaments and microtubules.

7.2 Cell Structure SC.912.L.14.3 The Cytoskeleton Microfilaments- Mostly made up of actin, Microfilaments help the cell move. Microtubules mostly made up of tubulins. Microtubules help the cell maintain its shape, and are also important in cell division (only in animals)

7.2 Cell Structure SC.912.L.14.3 Organelles that build proteins What organelles help make and transport proteins? Ribosomes synthesized proteins Golgi apparatus transports the proteins and other materials. Endoplasmic Reticulum assembles proteins and lipids.

7.2 Cell Structure SC.912.L.14.3 Ribosomes Ribosomes are small particle of RNA and protein found throughout the cytoplasm in all cells. Ribosomes produced proteins by following coded instructions from the DNA.

7.2 Cell Structure SC.912.L.14.3 Endoplasmic Reticulum ER is where lipids components of a cell are assembled along with proteins. Proteins made on the rough ER will be the ones that are released, or secreted from the cell. Two types of ER- Rough and Smooth.

7.2 Cell Structure SC.912.L.14.3 Golgi Apparatus Golgi Apparatus modifies, sorts, and packages proteins and other material from the endoplasmic reticulum for storage in the cell or release outside the cell. The post office of the cell

7.2 Cell Structure SC.912.L.14.3 Organelles that capture and release energy What are the functions of chloroplast and mitochondria? Chloroplast- Organelle that captures energy Mitochondria- Organelle that releases energy

7.2 Cell Structure SC.912.L.14.3 Chloroplast Chloroplast capture the energy from sunlight and convert it into food that contain chemical energy in a process called photosynthesis. Chloroplast contains chlorophyll.

7.2 Cell Structure SC.912.L.14.3 Mitochondria (All cells have mitochondria) Mitochondria are the power of the cell. (Powerhouse) Mitochondria convert the chemical energy stored in food into compounds that are more convenient for the cell to use. Both Mitochondria and Ceroplastic contain their own genetic material. ( Supporting the endosymbiotic theory)

7.2 Cell Structure SC.912.L.14.3 Cellular boundaries What is the function of the cell membrane? All cells have a cell membrane it protects the cell, and keeps its products safe. Plants have an additional cell boundaries the cell wall.

7.2 Cell Structure SC.912.L.14.3 Cell wall Main functions is to give support, shape, and protect the cell. Cells wall are porous (allowing material in) which allows water, oxygen, and other certain substances to access the cell.

7.2 Cell Structure SC.912.L.14.3 Cell Membrane All cells have a cell membrane, which is made by a lipid bilayer which give the cell the flexibility that it needs. The Cell Membrane is semi-permeable which means it allows some materials into the cell.

7.3 Cell Transport Sc.912.L.14.2 Passive transport What is passive transport? Passive transport if transport that does not require energy. It keeps the water levels in the cell constant.

7.3 Cell Transport Sc.912.L.14.2 Diffusion Diffusion: Process by which particles move from an area of high concentration to an area of lower concentration. Diffusion depends on random particle movements.

7.3 Cell Transport Sc.912.L.14.2 Facilitated Diffusion Facilitated diffusion- Molecules that cannot diffuse across the membrane pass through special proteins which is called Facilitated diffusion. Protein act like carriers making them easier to let some molecules go through.

7.3 Cell Transport Sc.912.L.14.2 Osmosis Aquaporin- Are water protein channels hat allow water to pass through them. Osmosis: Diffusion of water through some semi-permeable membranes.

7.3 Cell Transport Sc.912.L.14.2 Osmosis Some membranes are just permeable to water and nothing else. Water will keep diffusion until equilibrium is reached. After equilibrium is reached then both solution on each side of the membrane become isotonic. When both solution are not isotonic then one in hypertonic and the other hypotonic.

7.3 Cell Transport Sc.912.L.14.2 Osmosis pressure Osmotic pressure is the force by which a substance exerts on a semipermeable membrane. Is causes a hypertonic solution to shrink, and a hypotonic solution to swell.

7.3 Cell Transport Sc.912.L.14.2 Active Transport What is active transport? Active transport is the movement of materials against a concentration different. It requires energy. Sometime active transport can change the shape of cells.

7.3 Cell Transport Sc.912.L.14.2 Molecular transport Small molecules act like pumps in active transport. A large amount of energy is used to keep up active transport.

7.3 Cell Transport Sc.912.L.14.2 Bulk Transport Large molecules and solid clumps can be transported by Bulk Transport. Endocytosis is the process of taking materials into the cell by means of in folding. Exocytosis- Release of large amounts of materials.

7.3 Cell Transport Sc.912.L.14.2 endocytosis and exocytosis

7.4 Homeostasis and Cells SC.912.L.14.2 The cells as an organism How do individual cells maintain Homeostasis? Homeostasis: To maintain constant internal physical and chemical conditions. To maintain homeostasis, unicellular organism grow in response to the environment, transform energy and reproduce.

7.4 Homeostasis and Cells SC.912.L.14.2 Multicellular life How to cell of multicellular organism maintain homeostasis? The cells of multicellular organism become specialized for particular task communicate with one another. Multicellular organism cells don’t live on their own.

7.4 Homeostasis and Cells SC.912.L.14.2 Cell specialization Many cells are specialized for one purpose (Movement, reacting to the environment, Substances that the organism needs). ALL SPECIALIZED CELLS CONTRIBUTE TO HOMOESTASIS!!!!!!!!

7.4 Homeostasis and Cells SC.912.L.14.2 Levels of organization Cells<Tissue<Organ<Organ System Tissue- Group of similar cells Organ-Group of similar tissues Organ System- Group of similar organs

7.4 Homeostasis and Cells SC.912.L.14.2 Cellular communication Chemical signals are used to communicate from one cell to another. The receptor is the molecule that receive a signal.