Unit 1-1: General properties and types of cells
Prior knowledge (1.1):
● Discuss diversity in cell size, structures; cells as organisms versus cells in organisms; unicellular versus multicellular.
Cell size:
1)Bacteria cells are smaller (most are less than a micrometer)
-Diffusion limits cell size in bacteria due to surface to volume ratio because they need a higher surface to volume
ratio, to gain the CO2, or organic molecules they need (photosynthetic bacteria) thus they need to be smaller.
2)Eukaryotes are bigger, diversity in space, within some are specialized
Eg)nerve cells are longer 1 m, Ostrich egg is one big cell
Structures:
All: 1)Plasma membrane
2)Ribosomes
3)DNA
4)Cytoplasm
Cells as organisms versus cells in organisms:
Unicellular vs multicellular
1)composed of one cell(usually bacteria/ prokaryotes )eg) amoebas, bacteria vs
2)composed of multiple cells and unicellular (eukaryotic)
Unicellular vs multicellular
Unicellular Multicellular
Cell Single cell Multiple cells
Shape Irregular shape Well defined
Size Small in size, microscopic Larger in size, macroscopic
Cell Type Prokaryotic and eukaryotic (1-10 microns) Eukaryotic (10-100 microns)
Cell organisation Simple Complex
-membrane bound organelles
Reproduction Binary fusion (asexually) and splitting in two Mitosis (asexually)
Sexual (gamete fusion and meiosis)
Interpret a phylogenetic tree of the tree of life and identify the three domains that comprise the tree of life.
,Three domains:
1)Bacteria
2)Archaea
3)Eukarya
Bacteria and Archaea Eukaryotes
-Mostly single celled microorganisms that lack a -can be both unicellular and multicellular
nucleus and are therefore prokaryotes
-Have nucleus
-evolved via endosymbiosis between archaea and
bacteria
Targeted:
● Summarize the critical components of cell theory.
1)All organisms are made up of cells
2)The cell is the fundamental unit of life
3)Cells come from pre-existing cells
4)There is no life without cells; the cell is the smallest unit of life
Cell: simplest entity that can exist as an independent unit of life
List and evaluate the characteristics that define cells as the smallest unit of life.
1)Capacity to store and transmit information
In the central dogma: flow of genetic information (DNA) ,which is a double stranded helix,
four letter bases, directing to protein formation
, 1)Replication: Producing 2 identical replicas of DNA from one original DNA molecule
2)Transcription: process of making an RNA copy of a gene sequence
3)Translation: protein is synthesized from the information contained in a molecule of
messenger RNA(mRNA)
This flows from nucleic acids to proteins but not in opposite direction
2)Membrane that selectively controls movement in and out
3)Ability to harness energy from the environment
Converts energy from environment into a form that could be used/ Metabolism refers to all the
chemical rxns within cells convert energy from one form to another to build and break down
molecules
❧ Compare and contrast the structural properties of bacterial and eukaryotic cells.
History:
1st cell was prokaryotic (4B ago)
Some prokaryotic cells are single celled
Eukaryotes evolved 2B year ago from prokaryotic ancestors
Bacterial Cells Eukaryotic Cells
Nucleus Absent (nucleoid instead) Nucleus present
No membrane bound organelles Internal compartmentalization present
Circular DNA/chromosome Linear DNA/chromosome
Many contain plasmid- additional, small circles of No plasmid
DNA that replicate independently of cell’s circular
chromosome
Smaller in size (less than one micrometer) larger
Binary fission (asexual) Mitosis, meiosis
Use horizontal gene transfer
a)Transformation takes DNA from environment
b)Transduction: virus that infects bacteria
C)Conjugation (sexually ) when the DNA is
transferred from one bacterium to another using
a pilus
Prior knowledge (1.1):
● Discuss diversity in cell size, structures; cells as organisms versus cells in organisms; unicellular versus multicellular.
Cell size:
1)Bacteria cells are smaller (most are less than a micrometer)
-Diffusion limits cell size in bacteria due to surface to volume ratio because they need a higher surface to volume
ratio, to gain the CO2, or organic molecules they need (photosynthetic bacteria) thus they need to be smaller.
2)Eukaryotes are bigger, diversity in space, within some are specialized
Eg)nerve cells are longer 1 m, Ostrich egg is one big cell
Structures:
All: 1)Plasma membrane
2)Ribosomes
3)DNA
4)Cytoplasm
Cells as organisms versus cells in organisms:
Unicellular vs multicellular
1)composed of one cell(usually bacteria/ prokaryotes )eg) amoebas, bacteria vs
2)composed of multiple cells and unicellular (eukaryotic)
Unicellular vs multicellular
Unicellular Multicellular
Cell Single cell Multiple cells
Shape Irregular shape Well defined
Size Small in size, microscopic Larger in size, macroscopic
Cell Type Prokaryotic and eukaryotic (1-10 microns) Eukaryotic (10-100 microns)
Cell organisation Simple Complex
-membrane bound organelles
Reproduction Binary fusion (asexually) and splitting in two Mitosis (asexually)
Sexual (gamete fusion and meiosis)
Interpret a phylogenetic tree of the tree of life and identify the three domains that comprise the tree of life.
,Three domains:
1)Bacteria
2)Archaea
3)Eukarya
Bacteria and Archaea Eukaryotes
-Mostly single celled microorganisms that lack a -can be both unicellular and multicellular
nucleus and are therefore prokaryotes
-Have nucleus
-evolved via endosymbiosis between archaea and
bacteria
Targeted:
● Summarize the critical components of cell theory.
1)All organisms are made up of cells
2)The cell is the fundamental unit of life
3)Cells come from pre-existing cells
4)There is no life without cells; the cell is the smallest unit of life
Cell: simplest entity that can exist as an independent unit of life
List and evaluate the characteristics that define cells as the smallest unit of life.
1)Capacity to store and transmit information
In the central dogma: flow of genetic information (DNA) ,which is a double stranded helix,
four letter bases, directing to protein formation
, 1)Replication: Producing 2 identical replicas of DNA from one original DNA molecule
2)Transcription: process of making an RNA copy of a gene sequence
3)Translation: protein is synthesized from the information contained in a molecule of
messenger RNA(mRNA)
This flows from nucleic acids to proteins but not in opposite direction
2)Membrane that selectively controls movement in and out
3)Ability to harness energy from the environment
Converts energy from environment into a form that could be used/ Metabolism refers to all the
chemical rxns within cells convert energy from one form to another to build and break down
molecules
❧ Compare and contrast the structural properties of bacterial and eukaryotic cells.
History:
1st cell was prokaryotic (4B ago)
Some prokaryotic cells are single celled
Eukaryotes evolved 2B year ago from prokaryotic ancestors
Bacterial Cells Eukaryotic Cells
Nucleus Absent (nucleoid instead) Nucleus present
No membrane bound organelles Internal compartmentalization present
Circular DNA/chromosome Linear DNA/chromosome
Many contain plasmid- additional, small circles of No plasmid
DNA that replicate independently of cell’s circular
chromosome
Smaller in size (less than one micrometer) larger
Binary fission (asexual) Mitosis, meiosis
Use horizontal gene transfer
a)Transformation takes DNA from environment
b)Transduction: virus that infects bacteria
C)Conjugation (sexually ) when the DNA is
transferred from one bacterium to another using
a pilus
