760 likes | 877 Views
CELLS. CHAPTER 4 Video: Introducing the Cell (2.54) http :// http:// www.youtube.com/watch?v=gFuEo2ccTPA. Some Random Cell Facts. The average human being is composed of around 100 Trillion individual cells!!! It would take as many as 50 cells to cover the area of a dot on the letter “ i ”
E N D
CELLS CHAPTER 4 Video: Introducing the Cell (2.54) http://http://www.youtube.com/watch?v=gFuEo2ccTPA
Some Random Cell Facts • The average human being is composed of around 100 Trillion individual cells!!! • It would take as many as 50 cells to cover the area of a dot on the letter “i” WOW!!!
INTRODUCTION TO CELLS Cells were known since the 17th century, when the microscope was created.
HOOKE, ROBERT • English scientist (17th century). • Observed CORK CELLS (from a bark of a cork tree). Dead cells.
CELLS: “little boxes similar to the “cells” (rooms) where the monks live”,Hooke
LEEUWENHOEK, ANTON VAN • Dutch scientist (17th century). • Better microscope. • Observed ALGAE CELLS (seaweed from water). Living cells.
SCHLEIDEN, MATHIAS • German botanist (19th century). • Observed that ALL PLANTS ARE MADE OF CELLS.
SCHWANN, THEODOR • German zoologist (19th century). • Observed that ALL ANIMALS ARE MADE OF CELLS.
VIRCHOW, RUDOLF • German zoologist (19th century). • Observed that ALL CELLS COME FROM OTHER CELLS.
CELL THEORY 1. All living things are made of cells 2. Cells are the basic unit of life 3. Cells come from other cells Activity (optional): Research on Internet the Biography of one of the Scientist involved in the Cell theory.
How Has The Cell Theory Been Used? • The basic discovered truths about cells, listed in the Cell Theory, are the basis for things such as: • Disease/Health/Medical Research and Cures(AIDS, Cancer, Vaccines, Cloning, Stem Cell Research, etc.)
Some Parting Thoughts • It is amazing to think that the cells that make up our bodies are just as alive as we are. Humans are just an intricately designed community of cells, which must work together to survive.
CELLS • DIFFERENT SHAPES (different functions) Ex: Nerve cells (long connections)
DIFFERENT SIZE (mostly small). Some are huge. Ex: Nerve cells in giraffe’s spinal cord. (almost 6.5 feet long) Cells have to be small to be able to exchange nutrients and wastes with their environment. (www.cellsalive.com/howbig.htm)
Cells need ENERGY to: move, reproduce, grow… • They have 3 main parts: CELL MEMBRANE CYTOPLASM Control Center: NUCLEUS WS: Active Reading and Microscope
CAPSULE: Protection and Attachment to cells that bacteria infects. CELL WALL: Protection CELL MEMBRANE: Controls what enters and leaves the bacteria RIBOSOMES: Make proteins PILI: Attachment to cells. FLAGELLA: Movement CYTOPLASM: Liquid that contains all the organelles DNA: Genetic information. One short closed loop.
ARE BACTERIA GOOD OR BAD FOR YOU? • BOTH Good: Bacteria in intestines used to digest food, Bacteria in mouth to protect us from other Bacteria… Bad: diseases (Anthrax, Scarlet fever, Leprosy…)
WHERE DO BACTERIA LIVE? EVERYWHERE (deep oceans, volcanoes, human body…)
WHAT WAS THE FIRST LIVING ORGANISM IN EARTH? BACTERIA WS: Prokaryotes -Bacteria
PARTS OF A CELL WS: Cells and Their Organelles
Plasma or CELL MEMBRANE LOCATION (Where?): Surrounding ALL cells. FUNCTION (What for?): Allows materials to go in and out the cell (nutrients, wastes…). STRUCTURE (How does it look?): Double layer of PHOSPHOLIPIDS with PROTEINS (transport) and CHOLESTEROL (elasticity).
PHOSPHOLIPIDS have 2 sides: • HYDROPHILIC SIDE (“likes water”). • HYDROPHOBIC SIDE (“does not like water”)
The CELL MEMBRANE is known as a FLUID MOSAIC MODEL. It moves and it changes all the time.
CYTOPLASM LOCATION: InsideALL cells. FUNCTION: Contains all the organelles of the cell. STRUCTURE: It is made of a liquid called CYTOSOL and the ORGANELLES. CYTOPLASM= CYTOSOL + ORGANELLES
NUCLEUS LOCATION: InsideEUKARYOTICcells. (Bacteria or Prokaryotic cells DO NOT have Nucleus) FUNCTION: Control center of the cell (“Brain”). Contains the GENETIC MATERIAL. STRUCTURE: It is surrounded by a NUCLEAR ENVELOPE (nuclear membrane). It contains a liquid (NUCLEOPLASM) where the DNA (chromosomes) float.
CELL WALL LOCATION: Surrounds the cell membrane in PLANT CELL and PROKARYOTIC FUNCTION: Protection and support STRUCTURE: It is made of CELLULOSE
ENDOPLASMIC RETICULUM LOCATION: Inside EUKARYOTIC CELLS (animal and plant) FUNCTION: ROUGH E.R: It has RIBOSOMES attached. Ribosomes are where PROTEINS are made. SMOOTH E.R: It does not have RIBOSOMES. Makes and storages LIPIDS (fats) and CARBOHYDRATES (sugar) STRUCTURE: Membrane that connects nuclear envelope and cell membrane.
GOLGI APPARATUS LOCATION: Inside EUKARYOTIC CELLS (animal and plant) FUNCTION: Packages cell products in small sacs called VESICLES. STRUCTURE: Flat membranein cytoplasm.