BIOLOGY 103 UNIT 2 LECTURE EXAM 2026
| COMPLETE STUDY GUIDE & PRACTICE
QUESTIONS
| GRADED A+ | GUARANTEED SUCCESS
Updated 2026 Questions and Answers
100% Verified Exam Prep and Comprehensive
Rationales Included
,cytology study of cells
robert hooke English physician
Observed microscopic cavities in cork
First to use the word “cell”
Reminded him of the small rooms occupied by monks
Antonie Van Leeuwenhoek Dutch microscopist
"animalcules"
discovered protists & bacteria
Schleiden concluded that all plants are made of cells
Schwann concluded that all animals are made of cells
Virchow Proposed that all cells come from pre-existing cells; observed cell division
,cell theory 1. All organisms made of cells
2. Cells are basic units of structure & function of organisms (life)
3. Cells come from preexisting cells
cell size mostly microscopic
Frog egg (1mm) to some bacteria (1um)
why are cells so small Need large surface area of plasma membrane (relative to volume) to allow
nutrients/waste to enter/exit.
cell surface‑area‑to‑volume ratio requires that cells be small so they can be efficient
small cells Larger surface area to volume ratio
Advantageous for exchange of molecules
6:1 scale
large cells Surface area to volume ratio decreases.
Decreases efficiency of transporting materials in & out of cell
3:1 scale
, Microscopy Today compound light microscope
transmission electron microscope
compound light microscope Light passed through specimen
Then focused by series of glass lenses
Image formed on human retina
Magnification to 1000X
Resolution* of objects separated by 0.2 um (500X better than human eye)
Transmission Electron Microscope Abbreviated T.E.M.
Electrons passed through specimen
They are focused by set of magnetic lenses
Image formed on fluorescent screen
Magnification greater than compound light microscope
Resolution* of objects separated by 0.0002 um (100,000X better than human
eye)
resolution minimum distance between two objects that allows them to be seen as two
separate objects
| COMPLETE STUDY GUIDE & PRACTICE
QUESTIONS
| GRADED A+ | GUARANTEED SUCCESS
Updated 2026 Questions and Answers
100% Verified Exam Prep and Comprehensive
Rationales Included
,cytology study of cells
robert hooke English physician
Observed microscopic cavities in cork
First to use the word “cell”
Reminded him of the small rooms occupied by monks
Antonie Van Leeuwenhoek Dutch microscopist
"animalcules"
discovered protists & bacteria
Schleiden concluded that all plants are made of cells
Schwann concluded that all animals are made of cells
Virchow Proposed that all cells come from pre-existing cells; observed cell division
,cell theory 1. All organisms made of cells
2. Cells are basic units of structure & function of organisms (life)
3. Cells come from preexisting cells
cell size mostly microscopic
Frog egg (1mm) to some bacteria (1um)
why are cells so small Need large surface area of plasma membrane (relative to volume) to allow
nutrients/waste to enter/exit.
cell surface‑area‑to‑volume ratio requires that cells be small so they can be efficient
small cells Larger surface area to volume ratio
Advantageous for exchange of molecules
6:1 scale
large cells Surface area to volume ratio decreases.
Decreases efficiency of transporting materials in & out of cell
3:1 scale
, Microscopy Today compound light microscope
transmission electron microscope
compound light microscope Light passed through specimen
Then focused by series of glass lenses
Image formed on human retina
Magnification to 1000X
Resolution* of objects separated by 0.2 um (500X better than human eye)
Transmission Electron Microscope Abbreviated T.E.M.
Electrons passed through specimen
They are focused by set of magnetic lenses
Image formed on fluorescent screen
Magnification greater than compound light microscope
Resolution* of objects separated by 0.0002 um (100,000X better than human
eye)
resolution minimum distance between two objects that allows them to be seen as two
separate objects
