Lesson 1

Robert Hooke

made a 3-lens microscope and discovered cells in 1665

Antonie Van Leeuwenhoek

• clothing trader who worked with lens’ to see seams

• further developed the light microscope

• viewed the first living cell and called them animalcules (protozoa, bacteria, blood, and sperm cells)

• 1674

Matthias Schleiden and Theodore Schwann

• the cell theory

• spontaneous reproduction

• 1838-1839

Rudolph Virchow

• corrected cell theory

• cells come from other cells

• 1855

Modern Cell Theory

• all living organisms - cells

• basic unit of structure/function

• cell arise from pre-existing cells

Cell

smallest living unit that perform’s essential life functions

Essential life functions

Response to stimuli, reproductions, metabolism, growth and development, and evolution

Response to stimuli

interaction with environment

Reproduction

DNA replication, cell division, and inheritance of genetic information

Metabolism

obtaining and using energy for survival

Growth and development

traits coded in their genes

Evolution

natural selection acts on heritable variation system capable of Darwinian evolution

Nucleus

contains most DNA in a eukaryotic cell

The cytosol

membrane-enclosed organelles are distributed throughout the eukaryotic cell cytoplasm.

Cytoplasm

cytosol and organelles

Mitochondria

Cellular respiration site. Distinctive internal structure with a smooth outer membrane and a folded inner membrane for higher surface area.

• thought to have evolved from engulfed aerobic bacteria creating a symbiotic relation-ship.

Chloroplasts

capture the energy of sunlight and converts it into energy for the plant. Inner and outer membrane is folded and contains the green chlorophyll molecules that absorbs light energy.

Endoplasmic Reticulum

produces proteins and lipids. Rough section with ribosomes and smooth section. Produces many components of a Eukaryotes

Ribosomes

Structures that translate RNA into proteins

Golgi Apparatus

“Post office” composed of a stack of flattened, membrane-enclosed discs. Several can be present in a cell.

Cytoskeleton

network of protein filaments that can be seen criss-crossing in the cytoplasm. Some filaments include: actin, microtubules, intermediate.

Tissues

An ordered assembly of cells of the same type, specialized to carry out a particular function together.

Organs

A grouping of different tissues that forms a structural unit responsible for a defined function.

Organ systems

a set of organs and associated structures that work together to carry out a physiological function in a living organism

Genomes

• genome sequence comparisons produce a family tree of life that contains three major divisions.

• Bacteria - the most diverse

• Archea - discovered through DNA sequencing

• Eukaryotes - small slice of overall global diversity

Horizontal Gene Transfer (HGT)

• incorporation of Mitochondria

• incorporation of chloroplasts

Model organisms

E. cole, yeast, arabidopsis thaliana, caenorhabditis elegans, drosophila melanogaster, danio rerio, house mouse, and cultured human cells

Asgard Archaeon

• closest to eukaryotes

• related through endosymbiosis

• Asgard archaeon + endosymbiotes = endosymbiosis

Endosymbiotic theory

Mitochondria and chloroplasts were formerly free-living bacteria that became incorporated as endosymbionts with asgard archeaon