Cell Theory and Organelles PDF - Biology Notes

By Mrs. Hoskins SB1. Obtain, evaluate, and communicate information to analyze the nature of the relationships between structures and functions in living cells. a. Construct an explanation of how cell structures and organelles (including nucleus, cytoplasm, cell me...

By Mrs. Hoskins SB1. Obtain, evaluate, and communicate information to analyze the nature of the relationships between structures and functions in living cells. a. Construct an explanation of how cell structures and organelles (including nucleus, cytoplasm, cell membrane, cell wall, chloroplasts, lysosome, Golgi, endoplasmic reticulum, vacuoles, ribosomes, and mitochondria) interact as a system to maintain homeostasis  Cell Theory 1. All living things are made of cells. 2. Cells are the basic unit of life. 3. All cells come from other cells.  Cell Theory 1. Although all living things are made of cells, organisms may be: Unicellular – composed of one cell Multicellular – composed of many cells that may organize into tissues → organs → organ systems  Cell Theory 2. Cells are the most basic unit of life. – It is the smallest part of an organism that is still capable of all of life’s processes. – But they are VERY diverse. – Two types: Prokaryotic Eukaryotic  Cell Theory – Two types: Prokaryotic Eukaryotic Nucleus? no yes Membrane-bound organelles? no yes Division? binary fission mitosis Size of organisms? unicellular uni- or multicellular Yes, made of Only fungi and plants, Cell walls? peptidoglycan made of chitin or cellulose Ex. of organisms animals, plants, with this type of bacteria cell? fungi, protists  Cell Theory Although there are two main types of cells, ALL cells have: – Genetic material (DNA or RNA) – Cytoplasm – Cell membrane – Ribosomes  Organelles All cells have these four structures, but eukaryotic cells also have membrane-bound organelles. Organelles = specialized structures within the cell that work together to help the cell function – Think of them as “mini organs” within the cell working together for one main purpose → TO MAKE PROTEINS! Remember, eukaryotes include animals, plants, protists, and fungi, but we will focus mainly on plants and animals Animal cell Plant cell CELL (Plasma) MEMBRANE Structure Surrounds the outside of ALL cells! Made of two layers (known as the phospholipid bilayer) Job Controls what goes in and out of the cell Critical for communication and maintaining a stable internal environment (homeostasis) CELL (Plasma) MEMBRANE Phospholipid Bilayer Polar 2 layers of fats hydrophilic head – Fats = phospholipids Have hydrophilic (likes water) heads and hydrophobic (dislikes water) tails Nonpolar hydrophobic tails CELL (Plasma) MEMBRANE Phospholipid Bilayer Proteins embedded for transport Carbs embedded for structure Called “Fluid Mosaic Model” because it is composed of many parts that move around freely  CYTOSKELETON Structure Threadlike fibers Made of proteins Usually not pictured in a cell diagram Job Give the cell shape Can also move organelles around Provide structural support for animal cells (who don’t have a cell wall)  CYTOPLASM Structure Jelly-like substance Mainly made up of water Job Holds everything in place Provides a solution for chemical reactions to take place in  NUCLEUS Structure Contains genetic material (DNA) – When DNA appears spread out = chromatin – When DNA condenses it forms chromosomes Surrounded by a nuclear envelope/membrane with pores that control what goes in and out Job Protects the DNA that controls the activities of the cell  NUCLEOLUS Structure Inside of the nucleus Job Makes rRNA which make up ribosomes  RIBOSOMES Structure Made of proteins and rRNA Located on Rough ER and floating in cytoplasm Job Make proteins in a process called translation – Ribosomes on Rough ER make proteins to export out of cell – Ribosomes floating in cytoplasm make proteins to use within the cell  ROUGH ER (Endoplasmic Reticulum) Structure Has ribosomes on surface Hugs the nucleus Job Makes proteins!!! Packages them for secretion, send in vesicles to Golgi  SMOOTH ER (Endoplasmic Reticulum) Structure No ribosomes on surface Attached to Rough ER Job Makes lipids (membrane) Stores Ca+2  GOLGI APPARATUS Structure Folded membrane Job Gets vesicles of protein from the ER – Vesicles: like mini-carts that transport proteins around the cell Processes, sorts, and ships proteins where needed  LYSOSOMES Structure ANIMAL CELLS ONLY!! Contain enzymes Job Break down dead stuff (food, bacteria, old parts of cell, etc.) Can do programmed cell death (apoptosis)  VACUOLES Structure Small and numerous in animal cells One large central one in plant cells Job Storage (water, nutrients, waste, etc.)  CENTRIOLES Structure ANIMAL CELLS ONLY!! Made of microtubules 2 centrioles together = centrosome Job Appear during cell division Help cell divide by pulling chromosomes apart  CILIA and FLAGELLA Organelles associated with the cytoskeleton Structure Cilia: shorter, more numerous, like tiny oars – Similar projections that are short and numerous but don’t move are called microvilli Flagella: longer, fewer (1-3) ANIMAL (and bacteria) CELLS ONLY!! Job Cilia: move fluid across cell’s surface Flagella: move entire cell through extracellular fluid This image shows This image sperm cells, shows with microvilli on flagellum the outside tails, of a human swimming body cell towards an egg cell  MITOCHONDRIA Structure Two parts: inner membrane and matrix (fluid part) Job Where cellular respiration happens C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP) Breaks down chemical energy in food to release usable energy in the form of ATP  CHLOROPLAST Structure PLANT CELLS ONLY!! Two parts: grana (stacks) and stroma (fluid) Job Where photosynthesis happens 6CO2 + 6H2O → C6H12O6 + 6O2 Converts light energy from sun → chemical energy in sugar  CELL WALL PLANT (bacteria and fungi) CELLS ONLY!! Structure Made of cellulose (in plants), chitin (in fungi), and peptidoglycan (in bacteria) Job Protect and maintain shape  CENTRAL VACUOLE PLANT CELLS ONLY!! Structure 1 massive central structure Job Storage center  Practice Time 3 4 2 5 1 6 7 12 11 8 10 9  2 Practice Time 3 4 5 6 1 7 12 11 8 10 9  Practice Time Prokaryote Eukaryote  Practice Time Animal Cells Plant Cells  Keys 1.Cell membrane 2.Cytoplasm 1. Cell wall 2. Cell membrane 3.Mitochondria 3. Smooth ER 4.Golgi 4. Rough ER 5.Rough ER 5. Golgi 6.Ribosomes 6. Mitochondria 7.Vacuole 7. Vesicle or Ribosome (can’t be a small vacuole or lysosome 8.Centriole/Centrosome because those are only in 9.Lysosomes animal cells) 10.Nucleus 8. Central vacuole 11.Nucleolus 9. Cytoplasm 10.Chloroplast 12.Smooth ER 11.Nucleus 12.Nucleolus