Filetype Power Point PPTX | Posted on 31 Aug 2022 | 3 years ago
Authentication
digital resources
232x Filetype PPTX File size 0.70 MB Source: www.duplinschools.net
Robert Hook
• 1665 - Hook used a primitive microscope to
view cork. What he saw (cell walls) he
described as “cells” because they looked like
rooms in a monastery.
The Cell Theory (1835-1855)
Schleiden, Schwann, and Virchow
1. All living things are composed of cells.
2. Cells are the basic units of structure and
function in living things.
3. New cells are produced from existing cells.
Two categories of cells
• Eukaryotes (eu “true”; karyon “nucleus”) are
cells that have a nucleus.
• Prokaryotes (pro “before”) do not contain
nuclei.
• Nucleus – large membrane-enclosed structure
that contains the cell’s genetic material in the
form of DNA.
Comparison
Prokaryotes
• Smaller and simpler than eukaryotes
• Genetic material not contained in nucleus
• Carry out activities associated with living
things: grow, reproduce, respond to
environment and some move
• Example: bacteria
no reviews yet
Please Login to review.
