THE HISTORY OF CELL BIOLOGY
- Cell: the smallest unit that can carry on all of the processes of life
- Cell theory:
- 1) all living organisms are composed of 1 or more cells.
- 2) cells are the basic unit of structure and function in an organism.
- 3) cells come only from the reproduction of existing cells.
- Began being used in the 17th century
- Van leeuwenhoeks microscope:
- *the lenses were ground very precisely
- A light microscope:
- *uses optical lenses to magnify objects by bending light rays
- Used a microscope to view cork cells.
- Described cells as many little boxes.
- They appeared empty because:
- *They were dead plant cells.
- *The material inside was destroyed.
THE HISTORY OF CELL BIOLOGY
TIMELINE OF CELL BIOLOGY.
- Lacks a membrane bound nucleus.
- Lacks membrane bound organelles.
- Smaller than eukaryotic cells.
- Contains a membrane bound nucleus.
- Contains membrane bound organelles.
- Bigger then prokaryotic cells.
- Nucleus is an organelle that contains coded information in the form of
- DNA for regulating functions and reproduction and directs most activities
- Of the cell.
- Organelle: cell component that performs specific functions for the cell.
CELL ORGANELLES AND FEATURES
- NUCLEOPLASM: jelly like liquid that fills the nucleus
- NUCLEAR ENVELOPE: double membrane that surrounds the nucleus
- Microtubule: 1 of 3 structural elements that make up cytoskeleton.
UNIQUE FEATURES OF PLANT CELLS
- Plastid: organelle thats surrounded by a double membrane & has DNA
- Thylakoids: flattened membranous sacs that contain chlorophyll.
- Chlorophyll: green pigment that absorbs light
- & Captures energy for a plant cell.
NUCLEAR MEMBRANE SURROUNDS THE NUCLEUS, HAS A DOUBLE MEMBRANE.
- Smooth ER: does not have ribosomes
- Rough ER: has ribosomes.
- Carries materials through cells
- Ribosomes make proteins. ER aids in making proteins
- Ribosomes connect to ER or free float
Both ribosomes and ER are in all cells.
- Plant cells have a single, large vacuole.
- Animal cells have small vacuoles.
- Fluid filled sacs and largest organelle in plant cells.
- Store food, water, and toxic wastes.
- Store large amounts of foods or sugars in plants.
- Found in plants and algae cells.
- Green oval contains chlorophyll, gel like innermost
- Double membrane with inner membrane modified into sacs (thylakoids)
- Photosynthesis- uses energy from the sun to make food
- Releases oxygen.
- Found in All cells accept prokaryotes
- Stacks of flattened sacs "The Post Office"
- Have a cis & trans face
- Modify proteins made by the cells.
- Package & export proteins.
CENTRIOLES AND NUCLEOLUS
- Nucleolus found in all cells except prokaryote. Found inside the nucleus.
- Stores materials to be later used to make ribosomes.
- Centrioles are found in animal cells.
- They are paired structures near the nucleus. Made of Microtubule pairs
- Separates chromosome pairs during mitosis.
- Network of tubes and filaments that give a cell it's shape.
- & serves as tracks for the movement of organelles in the cell.
- Helps a cell divide.
- Helps a cell grow.
- Found in animal cells.
- Have 9-2 arrangement of microtubules.
- Makes the cell able to move.
- Found in bacteria
- Have 9-2 arrangement of microtubules
- Makes the cell mobile.
- ATP: special molecule that provides energy for a cells activities.
- Ecosystem: a community & all of the nonliving things that affect it.
- Population: a group of the same kind of organisms that live in the same area at the same time
- Community: all of the populations of different species that live and interact in an area.
- Multicellular: describes an organism that can exist only as a group of cells.