cell theory & the scientists involved robert hooke
TRANSCRIPT
Cell Theory&
The Scientists Involved
Robert Hooke
Cork oak (Quercus suber)
Anton Van Leeuwenhock
• Date: 1600’s• Theory: saw living organisms in pond
water never seen before (animalcules).• Occupation: invented the simple
microscope (single lens)
Cell Theory
• Cells are the structural units of all living things.(Cells carry on their own life functions)
• New cells can only arise from other cells by the process of cell division
• Viruses are not made up of cells.
• Also viruses do not carry out there own life functions.
• Where did the first cells come from?
• Mitochondria and chloroplasts contain their own DNA.
• Slime molds are multinucleated.
I’m the Herpes Virus
We’re Influenza Viruses!
• Slime molds do not have cells as a basic unit. They have an unorganized cytoplasm and many nuclei, they also do not have a distinct cell shape
Organelle• A specialized structure
in the cytoplasm of a cell that carries out a specific function.
Nucleus• Located in the center
of a cell, the nucleus is a large, dense, membrane-enclosed body that controls the cell’s metabolism and reproduction.
Nucleolus• Site of RNA
(ribonucleic acid) production
• A dense, granular body found in the nucleus
Cell membranes are semi-permeable. This means that the cell membrane only allows certain substances to pass through it. (Phospholipid bilayer)
Large structure comprised of smaller subunits.
According to the Fluid Mosaic Model the cell membrane Is a two layered structure composed of lipids and proteins.And is what we currently believe the cell membrane is composedof.
A hairlike organelle on the surface of a cell
with the capacity for movement
Green arrows point to Cilia
Flagella
• Involved in cell movement
• Only a few on the cell surface
• Whip-like tail• 9 microtubule doublets
arranged in pairs• 2 microtubules in
center
Phagocytosis• The process in which
large particles or small organisms are ingested into a cell.
PinocytosisThe process in which
liquids or very small particles are taken into a cell.
The substance is in contact with the surface of the cell membrane, the membrane pinches and forms a pouch.
Cytoplasm
• A watery material located between the cell membrane and the nucleus.
• Holds the organelles
Endoplasmic Reticulum
• A system of fluid filled canals or channels enclosed by membranes
• Serve as a path of transport throughout the cell
• Rough endoplasmic reticulum are lined by ribosomes.
Ribosome• An organelle that is
the site of protein synthesis in a cell.
• They are produced by the nucleolus.
Golgi Body
• Serve as packaging and storing centers for the secretory products of the cell
Lysosome
• Small, saclike structures surrounded by a single membrane
• Involved in the digestion of food within the food vacuoles of the cell
• Found in white blood cells, in multicellular organisms
MitochondrionThe powerhouse of the cell.
An oval, membrane enclosed organelle, in which most of the reactions of cellular respiration occur.
Mitochondrion
MicrofilamentA solid, thread-like organelle that can function as a supporting structure or aid in cell movement.
Act as “cross-bracing” in the cell.
Microtubules
• A long, cylindrical organelle found in cilia and flagella
• Are also involved in the movement of the chromosomes during cell division
• Composed of a protein called tubulin
Vacuole• A fluid-filled
organelle enclosed by a membrane.
• Stores waste and food.
• Occupies most of the space in the cytoplasm.
Specialized vacuoles include…Contractile Vacuole
• Extra water in the cell collects here and is expelled from the vacuole directly into the environment
• Works kind of like a water pump
Centrioles –found only in animal cells, these organelles aid in cell division.
In addition to the organelles previously mentioned, plants
also have additional organelles-
Contain a cell wall
Have chloroplasts
Chloroplasts• A membrane-enclosed
organelle found in the cells of some protists and almost all plants.
• They capture the sun’s energy and convert it into chemical energy during the process of photosynthesis.
SimilaritiesSimilarities ––
Plant and Animal Cells Both Plant and Animal Cells Both Have:Have:
A proper nucleus Cytoplasm
A cell membrane Chromosomes Mitochondria
Animals
Do not contain a cell wallDo not contain chloroplastsHave small vacuolesGenerally have spherical shape.Contain centrioles