Chapter 3 Sec. 2: Cell Features. Cell Theory. All living organisms are made of one or more cells. Cells are the basic unit for both structure and function . Cells come from preexisting cells.
Chapter 3 Sec. 2:Cell Features
- not by spontaneous generation (mice from rags, worms from horse hairs) we believe in biogenesis
Surface area= amount of cell membrane available
Volume= amount of material inside the cell
Cell division occurs!
Prokaryotes: Organisms without a nucleus or any membrane bound organelles (ex. Bacteria & simple algae)
Eukaryotes: Have nuclei & membrane bound organelles
(ex. Humans, fish, trees, sponges)
- gatekeeper of the cell
- is selectively permeable
(allows only certain substances to pass in or out)
- made of lipids and proteins (mostly lipids)
- two layers thick
The cell’s subway system
High energy requiring
cells like muscles!
- on the outside of cell membrane
- provides cell support & strength
- made of cellulose - a carbohydrate
- are storage spots in cytoplasm
- very large
- may store water, enzymes, waste products, or even toxins
- are membrane bound structures
- have their own type of DNA
- membrane bound structures
- store chlorophyll (green pigment needed for photosynthesis) so…
- chloroplasts are the sites of photosynthesis.
- are white structures inside cells
- are storage areas for produced food.
- Ex: Potato grains stained in lab.
- may be other starchy materials like corn, wheat
are the colored pigments seen in petals of flowers or in leaves in fall.