Docstoc

Chapter 3 The Basic Structure of a Cell

Document Sample
Chapter 3 The Basic Structure of a Cell Powered By Docstoc
					Basic Structure of a Cell




                            1
        Introduction to Cells
Cells are the basic units of organisms
Cells can only be observed under
 microscope
Basic types of cells:




 Animal Cell     Plant Cell   Bacterial Cell
                                               2
         The Cell Theory

• All living things are composed of cells.
• Cells are the basic units of structure
  and function in living things.
• New cells are produced from pre-
  existing cells.


                                             3
         Number of Cells
Organisms may be:
• Unicellular –
composed of one cell
• Multicellular-
composed of many
cells that may
organize


                           4
  Cells May be Prokaryotic or
          Eukaryotic
§ Prokaryotes include bacteria &
lack a nucleus or membrane-bound
structures called organelles
§Eukaryotes include most other cells
& have a nucleus and membrane-
bound organelles (plants, fungi, &
animals)
                                       5
           Prokaryotes
Nucleoid region
contains the DNA
•Cell membrane &
cell wall
• Contain ribosomes
(no membrane) to
make proteins in
their cytoplasm


                         6
          Eukaryotic Cell
Contain 3 basic cell
  structures:
• Nucleus
• Cell Membrane
• Cytoplasm with
  organelles


                            7
 Two Main Types of
  Eukaryotic Cells




Plant Cell   Animal Cell
                           8
         Organelles
Very small size
Can only be observed under a
  microscope
Have specific functions
Found throughout cytoplasm

                               9
  Organelles Found in Cells
 Examples of Organelles include:
Endoplasmic reticulum (rough & smooth) –
canals for movement
Golgi Bodies – wrap & export proteins
Nucleolus – makes ribosomes
Lysosomes – digests & gets rid of wastes
Ribosomes – makes proteins
                                           10
              Golgi Bodies
• Stacks of flattened
  sacs
• Have a shipping side &
  a receiving side;
• Packaging center of
  the cell.



                           Transport
                            vesicle
                                       11
                 Lysosome
• Contain digestive
  enzymes
• Break down food and
  worn out cell parts for
  cells




                            12
                 Nucleolus
• Cell may have 1 to 3
  nucleoli
• Inside nucleus
• Makes ribosomes that
  make proteins




                             13
Smooth & Rough Endoplasmic
        Reticulum
Smooth ER lacks
ribosomes &
makes proteins
USED In the cell
Rough ER has
ribosomes on its
surface & makes
proteins to
EXPORT
                             14
     Cell Powerhouse

Mitochondrion
( mitochondria )
     Rod shape
     Site of Cellular
     respiration


                        15
      In Animal Cells:
    Mitochondria



Active cells like
muscles have more
mitochondria

                         16
        Surrounding the Cell

Cell membrane
Lies immediately
 against the cell wall
 in plant cells
Made of protein and
 phospholipids
Selectively permeable
                               17
   Cell or Plasma Membrane

Cell membrane
Living layer
Controls the
 movement of
 materials into and
 out of the cell
Selectively
 permeable                   18
             Cell Wall

Cell wall
Nonliving layer
Gives structure and
 shape to plant and
 bacterial cells.


                         19
        Cytoplasm of a Cell

Cytoplasm
Jelly-like substance
 enclosed by cell
 membrane.
Contains organelles to
  carry out specific
         jobs

                              20
                 Control Organelle


Nucleus
Control center of the cell;
Contain the DNA
Bounded by a
 nuclear membrane
Contains chromosomes
                                     21
      Plant Cell Organelles
Chloroplast
Contain the green
 pigment chlorophyll;
Traps sunlight to
 make sugars (food);
Process called
 photosynthesis
                              22
            Plant Cell

Cell wall
Protect and support
  the enclosed
  substances
  (protoplasm);
Give shape to the cell


                         23
     Plant Cell Organelles
     Vacuole
Have a large central
 vacuole;

Contains cell sap
Sugars, proteins,
  minerals, wastes, &
  pigments
                             24
Different kinds of plant
         cells



   Onion Epidermal Cells   Guard Cells
  root hair




   Root Hair Cell
                                         25
vacuole               cytoplasm
                                   Animal cell

                                  No cell wall or
                                  chloroplast
                       nucleus    Stores glycogen
                                  in the
      mitochondrion               cytoplasm for
                                  food energy
                      cell
glycogen              membrane
granule                                             26
Animal Cell Organelles




• Near the nucleus
• Paired structures
• Help cell divide       27
Different kinds of animal
          cells


 white blood cell

                                                        Amoeba

 red blood cell


                                         muscle cell
                    sperm
 cheek cells
                            nerve cell
                                                       Paramecium   28
Similarities between plant
  cells and animal cells
   Both have a cell membrane
    surrounding the cytoplasm

     Both have a nucleus

  Both contain mitochondria

                                29
Differences between plant
   cells and animal cells
  Animal cells      Plant cells

  Relatively         Relatively
smaller in size    larger in size
Irregular shape   Regular shape
 No cell wall     Cell wall present
                                      30
Differences between Plant
  Cells and Animal Cells
  Animal cells        Plant cells
Vacuole small or    Large central
    absent             vacuole
Glycogen as food   Starch as food
     storage          storage
 Nucleus at the    Nucleus near cell
     center              wall          31
     Compound Microscope

• Instrument for
  observing small
  objects
• Magnify images
  up to 2000X
  their size


                           32
Different parts of
   a microscope

                     33
Revolving
                 Eyepiece
nosepiece
                 Body tube
Objective        Coarse
                 adjustment
Clip             Fine adjustment

Condenser        Arm

Iris diaphragm   Stage
                 Condenser
Mirror           control knob
                 Base
                                34
    Levels of organization
• Cells are
  grouped
  together and
  work as a
  whole to
  perform special
  functions


                             35
             Tissue
• A group of similar cells to
  perform a particular function
  – Animals : epithelial tissue,
    muscular tissue
  – Plants : vascular tissue,
    mesophyll


                                   36
             Organ
• Different tissues group together
  to carry out specialized functions
   – Heart : consists of muscles,
     nervous tissue and blood
     vessels
   – Leaf : consists of epidermis,
     mesophyll and vascular tissue

                                       37
The Structures of a Leaf
     (Plant Organ)
                  Chloroplast
                   Palisade
                 Mesophyll Cell
                 Spongy Mesophyll
                       Cell

                  Air Space

                  Stoma

                                  38
The Structures of a Heart
     (Animal Organ)




                            39
                 System
• Several organs and tissues work together
  to carry out a particular set of functions in a
  co-ordinated way
   – Human : digestive, respiratory, excretory,
     circulatory and reproductive systems
   – Plant : root and shoot systems




                                                    40
Human Body Systems
Examples of systems :
´ Digestive System
´ Respiratory System
´ Circulatory System
´ Nervous System
´ Reproductive System

                        41
Examples of a Human Body System




                              42
Examples of a Human Body System




                                  43
Examples of a Human Body System
         Circulatory System




                                  44
Examples of a Human Body System
          Nervous System




                                  45
   Levels of Organization
³CELLS   (muscle cells,nerve
 cells)
³TISSUES (muscle, epithelium)
³ORGANS (heart, lungs,
 stomach)
³SYSTEMS (circulatory system)
³ORGANISM (human)
                                46
It’s You!




            47

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:6
posted:4/29/2014
language:English
pages:47