Chapter 7 Cellular Structure and Function Section 1: Cell Discovery and Theory Section 2: The Plasma Membrane Section 3: Structures and Organelles Section 4: Cellular Transport

7.1 Cell Discovery and Theory Cellular Structure and Function 7.1 Cell Discovery and Theory

Checkpoint Can cells appear spontaneously without genetic material from previous cells? Explain why or why not.

Cellular Structure and Function Light Microscopes use glass lenses and light to magnify an image or stained specimen magnifies up to 1,000x actual size Compound scopes – use series of lenses, multiple lenses

Electron Microscopes WWII, 1940s Cellular Structure and Function Electron Microscopes WWII, 1940s Uses magnet to aim beam of electrons at thin slices of cells Magnifies up to 500,000x Can see individual parts of cells

Electron Microscopes Transmission EM Scanning EM Cellular Structure and Function Electron Microscopes Transmission EM Scanning EM

Cellular Structure and Function Tunneling EM Uses charged tip of a probe close to specimen so electrons “tunnel” through small gap Can magnify atoms!

Atomic Force Microscope (AFM) Cellular Structure and Function Atomic Force Microscope (AFM) very high-resolution type of microscopy demonstrated resolution of fractions of a nanometer (10-9)

1- genetic material to make what they need Cellular Structure and Function All cells: 1- genetic material to make what they need 2- bread down molecules to generate energy for metabolims Prokaryotic Cell Simple structure Contains plasma membrane Does not contain membrane-bound organelles 11,000x

Prokaryotic Cells Simple structure, small size Cellular Structure and Function Prokaryotic Cells Simple structure, small size Contains plasma membrane, nucleus Most are unicellular, such as bacteria Do not contain membrane-bound organelles Similar to first cells on Earth 11,000x

Cellular Structure and Function Eukaryotic Cells More complex structure, 1-100x larger than prokaryotes Contains plasma membrane, nucleus Contains nucleus and membrane-bound organelles Allow cell functions to happen in different parts of cell at same time Mostly multicellular organisms

Compare prokaryotic and eukaryotic cells Cellular Structure and Function Compare prokaryotic and eukaryotic cells

Cell diversity WHY 2 types of cells? Cellular Structure and Function Cell diversity WHY 2 types of cells? Eukaryotic thought to evolve from prokaryotes. Symbiotic relationship between pro and eu cells, called Endosymbiont Theory What would life be like if eukaryotic cells did not evolve, and Earth only had prokaryotes?

Chapter 7 Cellular Structure and Function 7.1 Formative Questions Robert Hooke and Anton van Leeuwenhoek designed microscopes that enabled them to see organelles within the cells they observed. A B true false FQ 1

Which is not a part of the cell theory? Chapter 7 Cellular Structure and Function Chapter Diagnostic Questions Which is not a part of the cell theory? Cells are the basic unit of structure and organization of all living things. All living things are composed of one or more cells. Cells arise only from previously existing cells. Cells are produced spontaneously as an organism grows. A B C D CDQ 2

If you wanted to see a three-dimensional Chapter 7 Cellular Structure and Function Chapter Diagnostic Questions If you wanted to see a three-dimensional image of DNA from a live specimen, which type of microscope would you use? scanning electron microscope transmission electron microscope scanning tunneling microscope simple light microscope A B C D CDQ 1

transmission electron microscope scanning electron microscope Chapter 7 Cellular Structure and Function 7.1 Formative Questions Which type of electron microscope directs electrons over the surface of a nonliving specimen, producing a three-dimensional image? transmission electron microscope scanning electron microscope scanning tunneling electron microscope atomic force microscope A B C D FQ 2

Plasma Membrane Thin, flexible boundary between cell and environment Cellular Structure and Function Plasma Membrane Thin, flexible boundary between cell and environment Allows nutrients in Allows waste to leave cell Also controls how much of substance can move through membrane “selective permeability”

Plasma membrane made of phospholipids arranged in a bilayer. Cellular Structure and Function Plasma membrane made of phospholipids arranged in a bilayer. phospholipid composed of phosphate head & 2 lipid tails

Fluid Mosaic Model Phospholipid bilayer allows other molecules to “float” in membrane. Other Components Proteins Cholesterol Carbohydrates fluid mosaic model

Proteins Transmit signals inside cell Act as a support structure Cellular Structure and Function Proteins Transmit signals inside cell Act as a support structure Provide pathways for substances to enter and leave

Cholesterol Prevents fatty acid tails from sticking together Cellular Structure and Function Cholesterol Prevents fatty acid tails from sticking together Keeps membrane fluidity, watery

Carbohydrates Identify chemical signals outside of cell Cellular Structure and Function Carbohydrates Identify chemical signals outside of cell

Cellular Structure and Function

Checkpoint Define the term selective permeability. Describe the benefit of a bilayer structure for the plasma membrane.

All cells, whether eukaryotic or prokaryotic, have a plasma membrane. Chapter 7 Cellular Structure and Function 7.1 Formative Questions All cells, whether eukaryotic or prokaryotic, have a plasma membrane. true false A B FQ 3

What feature of eukaryotic cells has enabled Chapter 7 Cellular Structure and Function 7.1 Formative Questions What feature of eukaryotic cells has enabled them to develop more specific functions than prokaryotic cells? nucleus organelles genetic material (DNA) larger cell size A B C D FQ 4

Which term describes the function of proteins Chapter 7 Cellular Structure and Function 7.2 Formative Questions Which term describes the function of proteins found on the outer surface of the plasma membrane? identifiers receptors supporters transporters A B C D FQ 5

Which component of the plasma membrane Chapter 7 Cellular Structure and Function 7.2 Formative Questions Which component of the plasma membrane contributes to the fluidity of the plasma membrane? phospholipids proteins carbohydrates cholesterol molecules A B C D FQ 6

What is the function of carbohydrates that Chapter 7 Cellular Structure and Function 7.2 Formative Questions What is the function of carbohydrates that stick out from the outer surface of the plasma membrane? They give the cell shape and enable it to move. They give the plasma membrane fluidity. They help the cell identify chemical signals. They hold the cell in place. A B C D FQ 7