300 likes | 577 Views
Objectives List scientists who contributed to the cell theory List the components of the cell theory Compare prokaryote and eukaryote cells Label a plant and an animal cell Know the functions of cell organelles. Early Contributions.
E N D
Objectives List scientists who contributed to the cell theory List the components of the cell theory Compare prokaryote and eukaryote cells Label a plant and an animal cell Know the functions of cell organelles
Early Contributions • Robert Hooke - First person to see cells, he was looking at cork and noted that he saw "a great many boxes. (1665) • Anton van Leeuwenhoek - Observed living cells in pond water, which he called "animalcules" (1673)
Theodore Schwann- zoologist who observed tissues of animals had cells (1839) • Mattias Schleiden - botanist, observed tissues of plants contained cells ( 1845) • Rudolf Virchow- also reported that every living thing is made of up vital units, known as cells. He predicted that cells come from other cells. (1850 )
The Cell Theory 1. Every living organism is made of one or more cells. 2. The cell is the basic unit of structure and function. 3. All cells arise from pre-existing cells. *Why is the Cell Theory called a Theory and not a Fact?
Checkpoint What was their contribution? Hooke Leeuwenhoek Schwann Schleiden Virchow The Cell Theory 1. All living things are made of _____ 2. Cells are the basic unit of _______ and ______ 3. Cells come from _______________ cells.
Cell Features ALL cell have these parts • Ribosomes – make protein for use by the organism • Cytoplasm – fluid material within cell • DNA – genetic material • Cytoskeleton – internal framework of cell • Cell Membrane – outer boundary, some things can cross the cell membrane
Comprehension Checkpoint Answer true or false • Robert Hooke was the first person to see cells. • Bacteria cells have a cell membrane. • The Cell Theory was developed by a single scientist. • Plant cells have cytoplasm. • Cells taken from fungi do not have DNA. • Cells can only come from pre-existing cells. • It only took five years to develop the Cell Theory.
Prokaryote Cells • Simple cells • Bacteria • These cells do NOT have a nucleus, their DNA is circular and floats in the cytoplasm Some bacteria have a tail-like structure called a flagella, that helps it to move. A capsule surrounds some bacteria and helps them avoid the body’s immune system
Bacteria Images Bacteria that causes Anthrax
Eukaryotic Cells Cells found in plants, animals, protists, and fungi The cell is composed of 4 main parts: • Cell membrane • Cytoplasm • Nucleus – “control center” of cell, DNA • Organelles – small structures that carry out specific functions (“little organs”)
Nucleus • Usually found at center of cell • Has a nuclear membrane & nuclear pores • Contains cell’s DNA in one of 2 forms • chromatin - DNA and proteins, becomes... • chromosomes - during cell division Nucleolus - which makes the cell’s ribosomes
True of False 1. All cells have a nucleus. 2. All cells have a cell membrane. 3. Eukaryote cells are the only cells to have a flagellum. 4. The nucleus contains the cell’s DNA. 5. Chromatin will become chromosomes. 6. The nucleolus makes the cell’s DNA.
Cell Organelles Mitochondria – cell’s energy center; turns food into a chemical energy called ATP The mitochondria is sometimes called the “powerhouse” of the cell
Cell Organelles Golgi Apparatus (Body) – processes, packages and secretes proteins. It is comparable to a factory or a post office. *A vesicle forms with Golgi to transport substances outside cell.
Cell Organelles Lysosome – Contains digestive enzymes, breaks things down, "suicide sac” Endoplasmic Reticulum – Transport, "intracellular highway". -Rough ER contains many ribosomes & is involved in protein synthesis -Smooth ERno ribosomes
Cytoskeleton – Helps cell maintain support & shape; movement a. microtubules- hollow tubes b. microfilaments-threadlike c. centrioles- only in animal cells; used during cell division (paired)
Vacuole – storage area for water and other substaces, plant cells usually have a large central vacuole
Protein Production The cell is like a factory. Its product is protein which goes to body to serve different functions. • DNA has instructions to build protein • Instructions are sent to ribosomes • The ribosomes build protein and sends it through ER • The proteins go to golgi where they are packaged for export
Plant Cells • CELL WALL – provides additional support • CHLOROPLASTS – contain green pigment, photosynthesis • CENTRAL VACUOLE – large water container
PLANT CELL Can you identify the parts?
CELL MEMBRANE • Selectively permeable ; it regulates what comes into the cell and what leaves the cell • It is composed of a double layer of phospholipids with proteins embedded throughout