Download Unit 2

CHAPTER 7
A TOUR OF THE CELL
OUTLINE
I. How We Study Cells
A. Microscopes provide windows to the world of the cell
II. A Panoramic View of the Cell
A. Prokaryotic and eukaryotic cells differ in size and complexity
B. Internal membranes compartmentalize the functions of a eukaryotic cell
III. The Nucleus and Ribosomes
A. The nucleus contains a eukaryotic cell’s genetic library
B. Ribosomes build a cell’s proteins
IV. The Endomembrane System
A. The endoplasmic reticulum manufactures membranes and performs many other
biosynthetic functions
B. The Golgi apparatus finishes, sorts, and ships cell products
C. Lysosomes are digestive compartments
D. Vacuoles have diverse functions in cell maintenance
V. Other Membranous Organelles
A. Peroxisomes consume oxygen in various metabolic functions
B. Mitochondria and chloroplasts are the main energy transformers of cells
VI. The Cytoskeleton
A. Provides structural support to cells for cell motility and regulation
VII. Cell Surfaces and Junctions
A. Plant cells are encased by cell walls
B. The extracellular matrix (ECM) of animal cells functions in support, adhesion,
movement and development
C. Intercellular junctions help integrate cells into higher levels of structure and
Function
OBJECTIVES
1. Distinguish between prokaryotic and eukaryotic cells.
Pro-bacteria, Eu-plant, animal, protests, fungi
4. Describe the structure and function of the nucleus, and briefly explain how the nucleus
controls protein synthesis in the cytoplasm.
Made of nuclear envelope, nucleolus, chromatin, nuclear lamina. This is the central part of the cell, it is the
storage for DNA and important for cell division because it carries heredity. The nucleus controls protein
synthesis in the cytoplasm by sending molecular messengers in the form of RNA. The m RNA conveys
messages to the cytoplasm then to Ribosomes to form primary structure of protein
5. Describe the structure and function of a eukaryotic ribosome.
Ribosomes are where the cell assembles proteins. Free and bound Ribosomes. Free for cytosol and bound
are for secretions in ie. Pancreas.
6. List the components of the endomembrane system, describe their structures and
functions and summarize the relationships among them.
A. Nuclear Envelope-surrounds nucleus can secrete mRNA through pores.
B. Endoplasmic reticulum- collects the gets all mRNA from envelope and shoots it through either to
Golgi or Ribosomes. Two parts Smooth and Rough (contains bound Ribosomes)
C. Golgi apparatus- pita stack, collects mRNA store, sorts ships to different parts of cell. Two parts
cis and trans, cis collect trans transport.
D. Lysosomes- breaks apart food entering the cell or even tissue. Acts also to recycle the dead
endomembrane parts in cytoplasm.
E. Vacuoles-used for storage and in plant cells controls size and also used for defense and attraction.
F. Plasma membrane-phospholipid surrounding cell that regulates the entrance and exit of particles
into cell.
7. Describe the vacuole & list types of vacuoles
Vacuole is used to store food.
a. food vacuole is used for food storage
b.
c.
contractile vacuole- pump excess water out of cell
central vacuole-used for storage, for protection or even attraction in plant vacuoles. Tonoplast
surrounds vacuole
8. Explain the role of Peroxisomes in eukaryotic cells.
These grab hydrogen and oxygen to form hydrogen peroxide, they break toxic waste apart. this grows
through the incorporation of proteins and lipids from the cytosol and split when they reach a certain size.
9. Describe the structure & function of a mitochondrion
The mitochondrion is the powerhouse of the cell it is used to produce ATP through cellular respiration.
Two membranes with lipid bi-layer in between.
11. Identify the three functional compartments of a chloroplast
Contains thyla. Stacked up like poker chips have also inner and outer membrane.
12. Describe probable functions of the cytoskeleton.
The probable functions of the cytoskeleton is to retain the shape of the cell especially in animal cells
13. Describe the structure, monomers and functions of microtubules, microfilaments and
intermediate filaments.
These are made of proteins that are involved in establishing the shape or in coordinating movements of the
cytoskeleton. Microtubes –motility for cellular activities. Intermediate filaments-maintain shape of cell.
Microfilaments, in muscle cells that move and change the shape of muscles
14. Explain how the ultrastructure of cilia and flagella relates to their function.
They make wavelike movements. Flagella long and few cilia short and many.
17. Describe the structure of intercellular junctions found in plant and animal cells, and
relate their structure to function.
Desmosomes- bears disc-shaped structure from which protein fibers extend into the cytoplasm. Holds
together tissues that undergo considerable stress.
Tight junctions- encircles each cell. For lining digestive tract where materials are required to pass
through cells to penetrate the blood stream.
Gap junctions- narrow tunnels that contain proteins that also prevent the cytoplasms of each cell from
mixing, but allows the passage of ions and small molecules. They allow communication between cells
through the exchange of materials or through the transmission of electrical impulses.
Plasmodesmata-narrow channels between plant cells. Material exchange through a plasmodesma
apparently occurs through the cytoplasm surrounding the desmotuble.
CHAPTER 8
MEMBRANE STRUCTURE AND FUNCTION
OUTLINE
I. Membrane Structure
A. Membrane models have evolved to fit new data: science as a process
B. A membrane is a fluid mosaic of lipids, proteins, and carbohydrates
II. Traffic Across Membranes
A. A membrane’s molecular organization results in selective permeability
B. Passive transport is diffusion across a membrane
C. Osmosis is the passive transport of water
D. Cell survival depends on balancing water uptake and loss
E. Specific proteins facilitate the passive transport of selected solutes
F. Active transport is the pumping of solutes against their gradients
G. Some ion pumps generate voltage across membranes
H. In cotransport, a membrane protein couples the transport of one solute to another
I. Exocytosis and endocytosis transport large molecules
OBJECTIVES
1. Describe the function of the plasma membrane.
Cell wall
5. Describe the fluid properties of the cell membrane and explain how membrane fluidity
is influenced by membrane composition.
Diffusoin an active transport and facilitated difusion
6. Explain how hydrophobic interactions determine membrane structure and function.
7. Describe how proteins are spatially arranged in the cell membrane and how they
contribute to membrane function.
8. Describe factors that affect selective permeability of membranes.
9. Define diffusion; explain what causes it and why it is a spontaneous process.
10. Explain what regulates the rate of passive transport.
12. Define osmosis and predict the direction of water movement based upon differences in
solute concentration.
14. Describe how living cells with and without walls regulate water balance.
16. Describe one model for facilitated diffusion.
17. Explain how active transport differs from diffusion.
20. Explain how large molecules are transported across the cell membrane.
21. Give an example of receptor-mediated endocytosis.
Proteins that transport cholesterol in blood
CHAPTER 12
THE CELL CYCLE
OUTLINE
I. The Key Roles of Cell Division
A. Cell division functions in reproduction, growth, and repair
B. Cell division distributes identical sets of chromosomes to daughter cells
II. The Mitotic Cell Cycle
A. The mitotic phase alternates with interphase in the cell cycle: an overview
B. The mitotic spindle distributes chromosomes to daughter cells: a closer look
C. Cytokinesis divides the cytoplasm: a closer look
D. Mitosis in eukaryotes may have evolved from binary fission in bacteria
III. Regulation of the Cell Cycle
A. A molecular control system drives the cell cycle
C. Cancer cells have escaped from cell-cycle controls
OBJECTIVES
2. Overview the major events of cell division that enable the genome of one cell to be
passed on to two daughter cells.
3. Describe how chromosome number changes throughout the human life cycle.
4. List the phases of the cell cycle and describe the sequence of events that occurs during
each phase.
5. List the phases of mitosis and describe the events characteristic of each phase.
6. Recognize the phases of mitosis from diagrams or micrographs.
8. Describe what characteristic changes occur in the spindle apparatus during each phase of
mitosis.
10. Compare cytokinesis in animals and plants.
11. Describe the process of binary fission in bacteria and how this process may have
evolved to mitosis in eukaryotes.
14. Explain how abnormal cell division of cancerous cells differs from normal cell division.