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Essentials of Human Anatomy & Physiology Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Seventh Edition Elaine N. Marieb Chapter 3 Cells and Tissues
Essentials of Human Anatomy & Physiology
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Seventh EditionElaine N. Marieb
Chapter 3Cells and Tissues
Journey into the cell….an introduction …..Journey inside the cell (3.5): https://www.youtube.com/watch?v=1fiJupfbSpg
Cells and Tissues
Slide 3.1Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Both carry out all chemical activities needed to sustain life. ∙Cells are the building blocks of all living things∙Tissues = groups of cells that are similar in structure and functionForm reflects function!
Main Ideas to recall…..
Anatomy of the Cell (in general…)
Slide 3.2Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
∙ All cells share general structures∙ Cells are organized into three main regions
∙Nucleus∙Cytoplasm∙Plasma membrane
Figure 3.1a
The Nucleus
Slide 3.3Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Control center of the cell
∙ Contains genetic material (DNA)
∙ Largest structure in the cell
Figure 3.1b
I am full of holes!
Plasma Membrane
Slide 3.7bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.2
Plasma Membrane
Lipids: hydrophilic/hydrophobic bilayer that creates the barrier of the cell and environment; used for transport
Proteins: used for transport, cell signaling or communication, anchorage, cellular junctions.
Plasma Membrane
Membrane Proteins: used for transport, cell signaling or communication, anchorage, cellular junctions.
-integral proteins vs peripheral proteins
-ion channels + carriers
Plasma Membrane Specializations
Slide 3.8aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
MicrovilliFinger-like projections that increase surface area for absorption
Form is significant for functions of the small intestine and nephrons of kidney.
Figure 3.3
Cytoplasm
Slide 3.9Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
cytoplasm: fluid like substance outside the nucleus and inside the plasma membrane Has 2 parts:
∙Cytosol: fluid that suspends other elements
∙Organelles: “metabolic machinery” of the cell = each with unique form&function
Cytoplasmic Organelles
Slide 3.10Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.4
Cytoplasmic Organelles
Slide 3.11Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
∙ Ribosomes∙Made of protein and RNA
∙Sites of protein synthesis
∙Can be free in cytoplasm or attached to rER.
Endoplasmic Reticulum (ER)
Slide 3.12Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
∙ Fluid-filled tubules ∙ Two types of
1. Rough ER∙ Studded with ribosomes∙ Site where building materials of cellular membrane are formed
2. Smooth ER∙ Functions in cholesterol synthesis and breakdown, fat metabolism, and detoxification of drugs
Rough ER: close to nucleus and has a lot of ribosomes.
Smooth ER: continuous with rER, but no ribosomes!
Golgi Apparatus
Slide 3.13aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
∙ Golgi apparatus∙Modifies and packages proteins∙Ships out proteins to where they need to go.
Cytoplasmic Organelles
Slide 3.13bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.5
Hydrolytic Organelles
Slide 3.14Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
1. LysosomesHas enzymes that digest nonusable materials2. PeroxisomesContains enzymesDetoxify harmful substances (often producing hydrogen peroxide in the process.)
Cytoplasmic Organelles
Slide 3.15Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
∙ Mitochondria∙ “Powerhouses” of the cell
∙ break down food (using oxygen) to produce ATP!
Cytoskeleton Network
Slide 3.16aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
∙protein structures that allow for support and movement within the cell.
∙Three different types1. Microfilaments2. Intermediate
filaments3. Microtubules
Cell Diversity
Slide 3.19aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.7; 1, 2
Cell Diversity
Slide 3.19bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.7; 3
Cell Diversity
Slide 3.19cCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.7; 4, 5
Cell Diversity
Slide 3.19dCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.7; 6, 7
Cell Membrane:made out of phospholipids arranged in a bilayer.
It is full of many other molecules as well….
Plasma Membrane
Slide 3.7bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.2
Membrane Videos: Passive process (simple/facilitated diffusion) (5m): https://www.youtube.com/watch?v=JShwXBWGMyY
Active transport: https://www.youtube.com/watch?v=owEgqrq51zY
Insulin in the human body (1.5): https://www.youtube.com/watch?v=OYH1deu7-4E
Membrane and Transport
Slide 3.20Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
movement of substance into and out of the cellselectively permeable : “controls” what gets in and out.
Two types of:∙Passive transport: no energy is required∙Active transport: requires energy
Passive Transport Processes
Slide 3.23Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Diffusion-Simple-Facilitated
Osmosis
Figure 3.8
Active Transport Processes
Slide 3.23Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Active Transport
Transport in Vesicles-Endocytosis-Exocytosis
p57
Figure 3.8
Passive Transport Processes
Slide 3.23Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
DiffusionParticles distribute in a solution
∙Movement is from high to low concentration
-(down a concentration gradient)
Figure 3.8
Passive Transport Processes
Slide 3.24bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Osmosis: simple diffusion of water through a membrane
Water moves toward high concentrations of solutes.
∙Your bodily fluids work to make sure the intracellular and interstitial fluids are equal to prevent a net movement of water into or out of the cell = BAD!
The net movement of H2O into and out of the cell should be equal.
Facilitated Diffusion: molecules are very large, must be “helped” through the membrane.∙Membrane proteins allow for the passage of these molecules (like glucose).
Diffusion through the Plasma Membrane
Slide 3.25Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.9
Active Transport Processes
Slide 3.27Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Transport molecules using energy! Why?∙ They are too big∙ Polarity differences (membrane = polar and nonpolar sections you must get through).
∙ They are going against the concentration gradient
Two common forms:1. Protein channels (solute pumping)2. Endo- and Exocytosis (bulk transport)
Solute Pumping
Slide 3.28aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Proteins “pump” substances into the cell such as:
- Amino acids- Sugars - Ions
ATP (energy) required because it goes against the gradient.
Active Transport Processes
Slide 3.28bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.10
Active Transport Movie: https://www.youtube.
com/watch?v=owEgqrq51zY
Slide 3.29aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
moves “a lot” of stuff!Types of bulk transport:
1. Exocytosis = (Exit)∙ Moves materials out of the cell in a membranous vesicle
∙ Vesicle migrates to plasma membrane∙ Vesicle combines with plasma membrane∙ Material is emptied to the outside
Bulk transport
Active Transport Processes - Vesicles
Slide 3.29bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.11
Slide 3.30aCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
2. Endocytosis = (endo = in)Extracellular substances are enclosed in a membranous vesicle and “swallowed”.
-Types of endocytosis∙Phagocytosis – cell eating∙Pinocytosis – cell drinking
Active Transport Processes
Slide 3.30bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.12
Phagocytosis vs. Pinocytosis
Slide 3.30bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.12
Phagocytosis vs. Pinocytosis
Slide 3.30bCopyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 3.12
Endo and Exocytosis movie: https://www.youtube.com/watch?v=owEgqrq51zY
Cell Life Cycle
Slide 3.31Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
1. Interphase∙ Cell grows and does its job
∙ Some cells stay in interphase forever, others go on to divide.
∙ If the cell will divide, the DNA will “copy” itself = DNA replication
2. Mitosis (Cell division)∙ Cell replicates itself∙ Function is to produce more cells for growth and repair processes
Cellular Divisions: Mitosis
Slide 3.33Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Two Subdivisions:2. Mitosis
∙ Nucleus divides into two.3. Cytokinesis
∙ Division of the cytoplasm∙ Begins when mitosis is near completion∙ Results in the formation of two daughter cells- each an EXACT copy of the previous cell, except half the size!
Mitosis Video- Image of PMAT structure: bit.ly/1owVTee
METAPHASE
INTERPHASE
TELOPHASE
ANAPHASE
PROPHASE
Mitosis: The Anatomy version
Slide 3.37Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Regulation:Regulating the cell cycle is very important to the human body!
∙ Not all cells divide! Ex. = Neurons
Pace is important, too...cells dividing to quickly?
CANCER = second leading cause of death in US!
Protein Synthesis:
Slide 3.37Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Gene = DNA segment that carries a blueprint for building specific proteinsProteins have many functions
∙Ex. Building materials for cells∙Ex. Act as enzymes (biological catalysts)
RNA is essential for protein synthesis∙ DNA to RNA to Proteins!
Mutations….• Mutations = accidental changes in the
genetic code.• Types:
1. Chromosomal Mutations•Effect entire chromosomes
2. Point Mutations•Effect genes
How do such small mutations affect cells?
Because if you change the DNA…..
You change the mRNA…..
You change the tRNA…..
If that = a different amino acid = a PROBLEM!
Things to remember about Mutation:Not all mutations causes problems!
• Mutations in not in genes DNA- who cares?•Mutations that code for the same, or chemically similar amino acid- who cares?•Sometimes these are called silent mutations.
Some mutations are good!• Without mutations our DNA couldn’t change = no more evolution.• Some mutations may make a protein more efficient at its job, or have “hidden” positive effects.
What can cause mutations?• Genetics: you inherit them as errors in meiosis (egg and sperm)• DNA replication = doesn’t copy correctly
• Environment: UV radiation, radiation, aging process (free radicals in body)•Drugs and Chemicals
•Mutagens: known to cause mutations•Carcinogens: known to cause cancerous mutations•Teratogens: cause mutations in developing baby.
•Random errors…woops
