chapter 6: life is cellular
DESCRIPTION
CHAPTER 6: Life is Cellular. I. History of Cells. A. Microscopes 1. Merchants first used hand lens to asses cloth quality 2. Hans & Zacharias Janssen (c. 1590)- Dutch lens makers invented first compound microscope. 3. Robert Hook (1665)- used light - PowerPoint PPT PresentationTRANSCRIPT
I. History of CellsA. Microscopes
1. Merchants first used hand lens to
asses cloth quality
2. Hans & Zacharias Janssen (c. 1590)-
Dutch lens makers invented first
compound microscope
3. Robert Hook (1665)- used light
microscope to look at cork;
Saw tiny chambers that he called “cells”
4.Anton Van Leeuwenhoek-
one of the first to use
microscopes to observe
nature
• Tiny organisms in H2O
• “Animalcules”.. bacteria
B. Cell Theory 1. When? 1838-1939 a. Matthias Schleiden
– All plants made of cells
b. Theodor Schwann– All animals made of cells
3. Cell Theory
a) All living things are composed of cells
b) Cells are basic units of structure and function in living things
c) New cells are produced from existing cells
II. Cell Types
A. Prokaryotes
1. Cells generally smaller
2. Do not have nuclei
3. Evolved first
4. All bacteria are prokaryotes• Ex: E. coli, staph
B. Eukaryotes 1. Contain nucleus 2. Cells are more complex- many eukaryotes form larger, multi-cellular organisms 3. Evolved after prokaryotes 4. Ex: Plants, animals, & fungi
III. Differences Between Plants & Animals
A. Plants Have (animals do not):
Cell wall, chloroplasts,
plastids, large central water
vacuole
B. Animals have (plants do not):
Centrioles, lysosomes
IV. Boundaries of the CellA. Plasma/Cell Membrane: - All cells
- Made of phospholipid monomers
- Double-layer, hydrophobic tails
in-between
- Hydrophilic heads line outside
and inside of cell
B. Cell Wall
- Plants only, used for support
and shape, protection
- Made of cellulose, hemicellulose,
and pectin
V. Cellular OrganizationA. Unicellular- “one cell”
1. Cell IS the organism
2. Must perform all functions of life, tend to be
more complex on a cellular basis than multi-
cell organisms
Ex: Include prokaryotes
& eukaryotes
B. Multi-cellular organisms
1. Cells do not live on their own
“Interdependent”
2. Each has a function for the
whole and cell specialization to
perform particular functions within organism•Ex: Pancreatic cells
C. 5 Levels of Organization1) Individual cells2) Tissues3) Organs4) Organ systems5) Organism
Cells• Specialization of functions• Nerve cells & muscle cells rely on other cells to
give them materials
Tissues• A group of similar cells that perform a particular
function
• Ex: cells in pancreas make digestive enzymes
• Most animals have 4 types of tissue:
»Muscle
»Epithelial
»Nervous
»Connective
Organs• Groups of tissues that
work together• Ex: muscle has
nerve cells & connective tissue
organ systems
• Group of organs that work together to perform a specific function
• 11 major organ systems in human body
END OF POWERPOINT
YOU MUST KNOW ALL THE ORGANELLES AND FUNCTIONS OF THE
STRUCTURES ON THE FOLLOWING SLIDES
Basic Cell Structures
• Typical cells are 5-50 μm
• Cell membrane–thin, flexible barrier around cell
• Cell wall–strong layer around cell membrane
(plants)–serve to protect and support
• Nucleus
–large structure containing cell’s genetic material and controls cell’s activities
• Cytoplasm
–material inside cell membrane but not including the nucleus
Basic Cell Structures
Cell wall
• Found in plants, algae, fungi, and almost all prokaryotes
» Animal cells do NOT have cell walls!
• Allow H2O, O2, CO2, and other substances to pass
• Function- to provide support & protection
• Made of CH2O’s and protein
• Plants- mostly cellulose
Nucleus
• Controls most cell processes• Contains hereditary information of DNA
» DNA codes to make proteins
• Chromatin» DNA bound to protein» spread throughout nucleus- condenses
during division
• Chromosomes» Distinct, thread-like, condensed chromatin» Contain genetic information
Nucleolus
• Small, dense region inside nucleus» Assembles ribosomes that make proteins
Nuclear Membrane» Double-membrane layer» Many pores to allow materials in and out- “doors”» RNA
Cytoskeleton
• Protein & calcium filaments»Act like skeleton, give shape»Cell movement
• Microtubules» hollow tubes; “tracks” that organelles use to
move» Important in cell division; separate
chromosomes» Cilia» Flagella
Endoplasmic reticulum• “Conveyor belt”
» Makes cell membrane components» Modifies proteins» rough and smooth
• Rough ER- involved in synthesis of proteins
» Gets appearance by ribsomes
Golgi Apparatus• “Quality control”
» Stack of membranes» Proteins made by RER move here» Enzymes modify carbohydrates and lipids
to proteins» Brings to the cell surface to be secreted
Lysosomes
• “Janitors”» Small, filled with enzymes» Break down lipids, carbohydrates, and
proteins into particles the cell uses» Break down old organelles
Vacuoles
• “Storage”» Store H2O, salts, proteins, CH2Os
• Support structures, like leaves and flowers» Plants often have a central, large vacuole
• Smaller vacuoles- “vesicles”
Chloroplasts
• “Solar panels”» Found in plants» Use energy from sunlight to make
energy/food- Glucose» “photosynthesis”
• Two envelope membranes» Stacks of membranes that hold green
pigment» DNA
Mitochondria
• “Power house”» Release energy from stored food
• Use energy to make high-energy compounds
» Cell growth, development, and movement
• 2 envelope membranes» DNA» Inherited from mom!
• Found in all eukaryotic cells