Life and Evolution: The images have big font size and reduced background color. Useful for smartphone,classroom and printouts. The rest is standard stuff.

1. Molecular Biology 1-1
put together by: Linda Fahlberg-Stojanovska
Disclaimer: I put these together for my kid for his smartphone.
However, I found most images had very small type and increased the
font size. I am posting it because another teacher might find this useful.
The sources are given.
If I have used anything illegally, write me and I will take it off.
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2. Contents
• Life
• Evolution

3. KEYWORDS
Life is the primary characteristic of organisms.
Organism is any connected living system capable of
• response to stimuli,
• reproduction,
• growth and development
• adaptation to environment
• homeostasis
Homeostasis is the property of organisms
• regulates its internal environment
• maintains a system of stable constant conditions like
• temperature or pH.
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4. KEYWORDS
Cell is the basic structural and functional unit of an
organism. The main purpose of cell is to organize.
Organelle is a subunit within a cell with a specific
function. It is usually membrane-bound.
Tissue is a layer of cells that are alike and work
together for a specific function. Tissue is the cellular
organizational level between cells and a complete organ.
Organ is a
• functional group of multiple tissues
• relatively independent part of the body
• carries out one or more special functions
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5. Organisms
can be classified as:
- single-cellular
- multi-cellular
Prokaryotes: bacteria and archaea
Eukaryotes: all other organisms!
Viruses are not organisms or cells.
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6. Prokaryotes
• unicellular
• no cell nucleus
• no mitochondria
• no membrane-bound organelles
Neither their DNA nor sites of metabolic activity are
collected together in a discrete membrane-enclosed
area.
Instead, everything is openly accessible within the
cell, some of which is free-floating.
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7. Prokaryotes vs. Eukaryotes
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teacherweb.com/IND/.../PROKARYOTIC_CELL_new_part_2.do
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8. Developmental Eras
• Earth is probably 4.5 billion years old
• 3.8 billion years of simple cells
(prokaryotes = bacteria and archaea)
• 3 billion years of photosynthesis,
• 2 billion years of complex cells (eukaryotes),
• 1 billion years of multicellular life,
• 600 million years of simple animals,
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9. Cell Size
Bacteria
• microbacteria ~150 nm
• E. coli 1,5 µm x 5 µm
• Exceptional: ~10 µm up to >100 µm
Human Cells:
• erithrocytes ~ 8 µm
• ovum (egg) ~ 100 µm
• nerve cells ~ 4 µm – 100 µm
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10. CELL
Cell is the basic structural and functional unit of an
organism.
Humans contain about
10 trillion (1013) cells.
Most plant and animal cells are
• between 1 and 100 µm
• Visible only under the
microscope.
http://toolboxes.flexiblelearning.net.au/demosites/series3/308/laboratory/studynotes/SN- 10
OilImmer.htm

11. Relative Sizes
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookCELL2.html
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12. KEYWORDS
Evolution is a science that investigates the
development of species.
Creationism is the belief that life on Earth was created
directly by a supernatural being.
Phylogeny is the science that studies the evolutionary
relationships between groups of organisms
(populations, species, ...).
Taxonomy is a system of classification of organisms
into groups according to their relationships and
evolutionary development
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13. Evolution and Mutation
Start with:
• Common origin of species.
• Genetic changes accumulate and lead to the emergence of
new characteristics.
• Genetic changes are the result of mutations, introduction of
new genes or recombination of genes.
• New characteristics are inherited.
• Natural selection: the environment represents a selection
pressure to force only characteristics that represent an
advantage for survival and reproduction.
• When populations are separated, different characteristics are
selected and new species develop.
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14. Evolution and Mutation
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http://en.wikipedia.org/wiki/File:Mutation_and_selection_diagram.svg

15. Classification Organisms - Domains
Category: Domain
There are 3 domains.
- Bacteria
- Archaea
- Eukaryotes
In 1990, the category “Domain” was added after C. R. Woese
distinguished Bacteria and Archaea based on differences in their
rRNA 16S
The three-domain system adds the level of classification Domains
above the level of Kingdoms.
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16. Taxonomy
DOMAIN Eukaryota
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http://en.wikipedia.org/wiki/Domain_%28biology%29

17. Kingdoms = 6
Prokaryotes: eubacteria, archaebacteria
Eukaryotes: protista, plants, animals, fungi
History of Kingdoms
Linnéas: 2 (animals and plants)
~1960: 4 basic divisions
prokaryotes and eukaryotes
~1969: 5 (fungi is added)
~1980: 6
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http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookdiversity_3.html

18. History of Taxonomy
On the Earth there are 5-100 million different species of organisms.
They differ in morphology, biochemical and genetic characteristics.
The first really successful attempt at grouping of organisms was
carried out by Linnaeus with the introduction of species and genera.
Species representing "all instances of creatures” that are each equal
to the smallest details of physical structure.
Darwin: " “all true classification is genealogical”
Ernst Mayer (~ 1940): biological species is a population or set of
populations who can breed with each other and have fertile
offspring.
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19. Keywords
• Morphology (biology): the study of the form or shape of an
organism.
• Biochemical Characteristics: characteristics which describe
the chemical substances and vital processes occurring in
living organisms.
• Genetic Characteristics: characteristics which are related to
heredity and the variation of inherited characteristics
among similar or related organisms.
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20. Genotype vs. Phenotype
Genotype: All of the genetic code of an organism.
Phenotype: All of the properties of an organism.
Phenotype reflects the genotype, as well as environmental influences
(diet, climate, injuries, lifestyle, …).
http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel/genes/genesrev_print.shtml
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21. Phylogenic Tree
Phylogenic tree can be drawn on the basis of:
- similaritiesbetween organisms
(fosils and their age, anatomy,…)
- differences between their amino acids and proteins
- differences between nucleotides in their DNA and RNA
Differences based on molecular biology is called
molecular phylogeny.
A node (taxa) joined together in the tree implies
“descended from a common ancestor”.
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22. Phylogenetic Tree for the 3 Domains
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http://en.wikipedia.org/wiki/Phylogenetic_tree

23. Dots indicate common ancestor.
Numbers indicate “relative” amount of change in genome.
Phylogenetic tree based on similarities between genome sequences.
The genome is an organism’s complete set of DNA.
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https://www.llnl.gov/str/June05/Ovcharenko.html