definition of theory
hypothesis that has been tested many times and has not yet been proven wrong
who dicovered cells while looking at cork under microscope
Robert Hooke
who described cells as tiny boxes or honey comb and thought cells only existed in plants and fungi
Robert Hooke
when did Robert Hooke discover cells
1665
who used a handmade microscope to observe pond scum
Anton van Leeuwenhoek
who discovered single-cell organisms
Anton van Leeuwenhoek
who observed blood cells from different animals and was the first to observe living cells
Anton van Leeuwenhoek
when did Anton van Leeuwenhoek contribute to cell theory
1673
what is spontaneous generation
living things come from nonliving things
who disproved spontaneous generation with an experiment with flies and meat
Francesco Redi
who disproved spontaneous generation with broth experiment
Louis pasteur
who found all plants are made of cells
Matthias schleiden
when did Matthias schleiden find all plants are made of cells
1838
who found all animal tissue is made of cells
Theodor Schwann
when did Theodor Schwann find all animal tissue is made of cells
1839
who through studying diseases found that all cells come from pre existing cells
Rudolph Virchow
when did Rudolph Virchow find all cells come from pre existing cells
1858
what are the parts of the traditional cell theory
- all organisms are made of one or more cells and cells come from other cells
- cells are the basic units of life in all living things
- cells have specialized structures and functions which are necessary for life
what are the parts of the modern cell theory
- energy flow occurs within cells
- cells contain hereditary info (DNA) that is passed from cell to cell during cell division
- all cells are similar in chemical composition in organisms of similar species
how many cells are in the human body
75 to 100 trillion cells
what are the levels of organization in an organism
atoms - compounds/biomolecules - organelles - cells - tissues - organs - organ systems - organism
tissue
group of similar cells grouped together
organ
different tissues grouped together
organ system
organs and tissues working together
