Transcript Eukaryotic and Prokaryotic Cells

Eukaryotic and
Prokaryotic Cells
AHMP 5406
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
1
Features All Cells Share
Hereditary info stored in DNA
Proteins are used as catalysts
DNA replication occurs through templated
polymerization
Hereditary info transcribed into RNA
RNA translated into protein
Later we will discuss these things in
greater detail
From DNA to Protein
(Why is this eukaryotic?)
1
Prokaryotic cells:
No membrane bound organelles
Simple genome organization
Genes usually do not have introns
Between 500 and 4000 genes

M. genitalium has 477 genes
Great degree of diversity
Unicellular
1
Mycoplasma
genitalium
1
Eukaryotic cells
All organelles are membrane-bound
Complex genome organization
Large genome size
Between 6,000 and 30,000 genes
Genes have introns

Where is the genetic diversity?
Large amount of regulatory DNA

To control gene expression
High degree of genetic redundancy
Unicellular or multicellular
1
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
1 and 2
General eukaryotic cell
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
3
Cells can be powered by different
energy sources
I eat other living things!

Organotrophic
Animals
Protists etc.
I need a tan?

Phototrohpic
Bacteria
Plants
Algae
I eat dirt?

Lithotropic
Arcaebacteria
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
4
Eukaryotic cell may have been
predators
The primordial eukaryotic cell may have
survived by eating other cells
This would require:




A large cell
A flexible membrane
An elaborate cytoskeleton
Protected DNA (in an organelle, which one?)
4
Dinidium is a cilliated protozoan
Lunch!
He looks hungry
4
4
4
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
5
Genome organization in Prok. and
Euk.
Prokaryotes

Circular DNA
mtDNA very similar
Eukaryotes


Linear DNA
nuclear DNA
5
Prokaryotic DNA
5
Eukaryotic DNA
DNA packaged in a
chromosome
Linear DNA
Associated proteins
More details later
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
6
Ways to generate new genes from preexisting genes
Intragenic mutation

Simply a mutation in the sequence
Gene duplication

Whole gene is just recopied into different part of the genome
DNA segment shuffling

Similar genes may exchange segments
Horizontal transfer

Cell to cell transfer of genetic material
e.g. Plasmids
ancient mitochondrial genes
Viruses
Sex
6
Gene Families
Created by generation of different genes
from a precursor
Speciation results in orthologous genes

An organismal phylogeny is produced
Gene duplication can result in paralogous
genes

A gene phylogeny is produced
Objectives:
1.
2.
3.
4.
5.
6.
7.
Discuss the key differences between prokaryotic and
eukaryotic cellular components
Describe the basic structure of mammalian eukaryotic
cells
Discuss the different nutritional classes
Explain the endosymbiotic theory and development of
organelles in the Euk. cell
Compare and contrast the genome organization of
prokaryotes versus eukaryotes
Compare the different ways new genes are generated
from existing genes
Explain why the human genome is complex
7
The human genome is complex:
Partly because of duplications
7
Regulatory
DNA is
everywhere
in eukaryotic
genomes
7
mRNA Structure
7
Comparative Genome Sizes