Cells

1
Cells

• Structure and Function

2
Introduction to cells

• Cell Theory
• all living things are composed of one or more
  cells
• cells are the basic units of structure and
  function in an organism
• cells come only from existing cells

3
Cell Diversity

• Size
• limited by outer surface area and volume
• why is this important?
• Shape
• form reflects function
• nerve cells
• skin cell

• Internal Organization
• internal structures
• organelles
• cell membrane
• nucleus
• Eukaryotes
• plant
• animal
• Prokaryotes

4
Parts of the Eukaryotic Cell

• Organelles
• mitochondrion
• ribosome
• endoplasmic reticulum
• golgi apparatus

• lysosome
• Microfilaments
• cillia
• nucleus
• vacuole
• plastid

5
Mitochondria

• Transfers energy from organic compounds to ATP
• ATP drives most of the chemical reactions that
  occur in the cell
• more in cells that have high energy requirements

6
Ribosome

• Most numerous organelle
• assemblage of two organic compounds
• protein and RNA
• Free or attached
• two parts

7
Endoplasmic Reticulum

• Membranous tubules and sacs
• intercellular highway, path for molecules to move
  from one part of the cell to another
• two types
• rough
• makes protein
• smooth
• steroids
• calcium levels
• liver breakdown

8
Golgi Apparatus

• Packaging, processing and secreting
• system of membranes
• modifies proteins for export

9
lysosomes

• Small spherical organelles that enclose
  hydrolytic enzymes
• early development
• digestion
• old organelles
• viruses
• bacteria

10
cytoskeleton

• Maintains shape and size
• network of long protein strands located in the
  cyotsol
• Microfilaments
• actin
• muscle contraction
• microtubules
• spindle fibers

11
Cilia and flagella

• Hair like organelles that extend from the surface
  of the cell
• play a role in movement
• Cilia
• short and present in large numbers
• line cells
• Flagella
• long and less numerous
• whipping back and forth

12
Nucleus

• Nuclear matrix
• nuclear envelop
• chromatin
• chromosomes
• nuclear pores
• nucleolus
• ribosomes made

13
Plant cells

• Three additional structures
• cell walls
• vacuoles
• plastids

14
Cell Wall

• Made of cellulose
• pores in structure allow for transport of ions
  and molecules
• Lies outside the cell membrane
• helps support and protect the cell
• secondary wall
• between primary and membrane
• stops growth
• wood

15
Vacuoles

• Fluid filled organelles
• store enzymes
• metabolic waste
• can occupy up to 90
• apple

16
plastids

• Two membrane bound organelles
• Store
• starch
• fat
• pigments
• types
• chloroplasts

17
chloroplast

• Thylakoid
• flattened membranous sacs
• sunlight is converted into chemical energy
• give leaves and fruit and flower color

18
Multicellular Organization

• Tissues
• organs
• organ systems

• Evolution of Multicellular organism
• colonial organisms
• specialized in performing functions
• cell in cell