The Cell
Copyright 2010, John Wiley & Sons, Inc. Chapter 3: The Cellular Level of Organization Cells are the smallest living things Cells are the structural and functional subunits of all of our body systems Cell Biology is the study of cells, their internal structures, and the chemical reactions that occur within them
Copyright 2010, John Wiley & Sons, Inc. Cells Are Made of Three Main Parts Every cell has 3 principal parts: – The plasma membrane is the flexible outer surface of the cell – The cytoplasm contains numerous organelles surrounded by cytosol – The nucleus is a large organelle that contains the cells chromosomes
Cell Organelles Work with a partner. List all of the organelles found in a human cell. Include their functions and any other information you recall about them. NEXC8 NEXC8
Bozeman Science Review cellular-organelles cellular-organelles
The Inner Life of the Cell An amazing look at the complexity of our cells. Watch this video with the volume turned off. Just appreciate how much happens in our cells all the time.
Cell structures and Organelles 1.Cytoplasm= contains organelles, H2O, proteins, Carbs, lipids, and inorganic substances. Cytosol=liquid portion of cytoplasm 2.Nucleus= contains DNA
Copyright 2010, John Wiley & Sons, Inc. Nucleus - The Central Control Center of a Cell
Copyright 2010, John Wiley & Sons, Inc. Chromosomes, Chromatin, and DNA Our genome consists of 23 pairs of chromosomes Each chromosome contains DNA combined with histone proteins to form chromatin The histones allow the DNA to be tightly packed After DNA replication, sister chromatids are connected at the centromere
Copyright 2010, John Wiley & Sons, Inc. Chromosomes, Chromatin, and DNA
3. Ribosomes= site for protein synthesis. Free floating or bound to ER
Copyright 2010, John Wiley & Sons, Inc. Ribosomes - The Site of Protein Synthesis
4. Rough Endoplasmic Reticulum = membranous set of tubes studded with ribosomes. Make proteins that are exported from the cell
5. Smooth ER= lack ribosomes. Lipid synthesis
Copyright 2010, John Wiley & Sons, Inc. Endoplasmic Reticulum
6. Lysosomes= contain digestive enzymes, formed from golgi. Digests toxins and worn out cells
Copyright 2010, John Wiley & Sons, Inc. Lysosomes, Peroxisomes, Proteasomes Lysosomes contain digestive enzymes used to break down: – Ingested material – Worn-out parts of cells – Destroy the whole cell Peroxisomes contain oxidative enzymes important in metabolism Proteasomes break down worn out or unneeded proteins
Copyright 2010, John Wiley & Sons, Inc. Lysosomes, Peroxisomes, Proteasomes
7. Mitochondria= double membrane (inner folds=cristae ) powerhouse of the cell make ATP
Copyright 2010, John Wiley & Sons, Inc. Mitochondria
8. Golgi Apparatus=stacked membranes. Store, modify, package proteins to be shipped out of the cell
Copyright 2010, John Wiley & Sons, Inc. Golgi Complex
Copyright 2010, John Wiley & Sons, Inc. Golgi - Processing and Packaging of Proteins
9. Peroxisomes=contain enzymes involved in the metabolism of hydrogen peroxide. Detoxify toxins in the liver
10. Cytoskeleton a. microfilaments= rod-like structures consisting of protein actin and myosin. function: muscle contraction, support and movement b. microtubules= cylindrical consist of protein tubulin function: provide support and movement. Form flagella, cilia, centrioles and the mitotic spindle
Copyright 2010, John Wiley & Sons, Inc. Cytoskeleton - A Network of Protein Filaments that Stretches Throughout the Cytosol Major functions: – Determining cell shape – Organizing the contents of the cell – Moving organelles – Moving chromosomes during cell division – Creating and moving membrane vesicles (in phagocytosis, etc.)
Copyright 2010, John Wiley & Sons, Inc. Cytoskeleton - A Network of Protein Filaments that Stretches Throughout the Cytosol
11. Centrioles= made of microtubules involved in cell division
Copyright 2010, John Wiley & Sons, Inc. Centrosome Makes new microtubules in nondividing cells Forms the mitotic spindle during cell division
Copyright 2010, John Wiley & Sons, Inc. Centrosome