Presentation on theme: "Cell Unit Learning Goal 2. Prokaryotic Cells Believed to be the first cells to evolve. Lack a membrane bound nucleus and organelles. Genetic material."— Presentation transcript:
Cell Unit Learning Goal 2
Prokaryotic Cells Believed to be the first cells to evolve. Lack a membrane bound nucleus and organelles. Genetic material is naked in the cytoplasm Ribosomes are only organelle. Http.micro.magnet.fsu.edu/cells.html
Eukaryotic Cells “True nucleus”; contained in a membrane bound structure. Membrane bound organelles. Thought to have evolved from prokaryotic cells.
Prokaryotic vs. Eukaryotic
Cell Wall The main function of the cell wall is to provide support and protection for the cell. Found in plant and prokaryotic cells. Formed from fibrils of cellulose molecules in a “matrix”.
Cell Membrane Layer of phospho-lipids and proteins that separates cytoplasm from external environment. Regulates flow of material in and out of cell. Selectively permeable to allow substances to pass into and out of the cell.
Cytoplasm Also known as protoplasm is location of growth, metabolism, and replication. Is a gel-like matrix of water, enzymes, nutrients, wastes, and gases and contains cell structures.
Ribosomes Translate the genetic code into proteins. Found attached to the Rough endoplasmic reticulum or free in the cytoplasm. 60% RNA and 40% protein. html
Rough Endoplasmic Reticulum Network of continuous tubes, studded with ribosomes. Manufactures, processes, and transports proteins for export from cell. Continuous with nuclear envelope. creticulum.html
Smooth Endoplasmic Reticulum Similar in appearance to rough ER, but without the ribosomes. Involved in the production of lipids, carbohydrate metabolism, and detoxification of drugs and poisons. Metabolizes calcium.
Lysosome Single membrane bound structure. Found mostly in animal cells. Contains digestive enzymes that break down cellular waste, old cell parts, and nutrients for use by the cell.
Golgi Apparatus (Complex) Modifies proteins and lipids made by the ER and prepares them for export from the cell. Encloses digestive enzymes into membranes to form lysosomes. atus.html
Mitochondria Membrane bound organelles that are the site of cellular respiration (ATP production) Powerhouse of the cell. rion/html
Nucleus Double membrane- bound control center of cell. Brain of the cell. Separates the genetic material from the rest of the cell. ml
Parts of the nucleus: Chromatin - genetic material of cell in its non-dividing state. Chromosomes – Condensed chromatin ready for cell division. Figure 2: Different levels of DNA condensation. (1) Double-strand DNA. (2) Chromatin strand (DNA with histones). (3) Chromatin during interphase with centromere. (4) Condensed chromatin during prophase. (Two copies of the DNA molecule are now present) (5) Chromosome during metaphase.interphaseprophasemetaphase
Parts of the nucleus: Nucleolus - dark-staining structure in the nucleus that plays a role in making ribosomes Nuclear envelope - double membrane structure that separates nucleus from cytoplasm.
Centrioles Found only in animal cells. Self-replicating Made of bundles of microtubules. Help in organizing cell division. ntrioles.html
Cytoskeleton Solid rods of globular proteins. cytoskeleton offers support to cell structure. ments.html
Chloroplast Site of photosynthesis Membrane bound structure. Contains chlorophyll tml
Vacuole Store water and nutrients needed by the cell. Help support the shape of the cell. Plants have a large central vacuole. Other types of cells have a much smaller vacuole.