Topic 1D Cell Structure & Organelles Notes

Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 http://www.youtube.com/watch?v=g4L_QO4WKtM May 13­7:19 PM Do Now Problems: 1. An element on the periodic table has 3 energy levels and 5 vale...

Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 http://www.youtube.com/watch?v=g4L_QO4WKtM May 13­7:19 PM Do Now Problems: 1. An element on the periodic table has 3 energy levels and 5 valence electrons. What is the element? 2. How many electrons are present in each of the first 4 energy levels? May 12­7:45 AM 1 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Cell Organelles ­ Give 1, Get 1! Dec 3­8:06 AM Cell Structure and Organelles Dec 7­9:08 AM 2 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Cell Membrane Made of phospholipids and proteins. Separates the cell from other cells and from surrounding fluids. Selectively permeable membrane that allows some molecules to pass through but not others. Some cell membranes have many small, fingerlike projections called microvilli. Microvilli are common in cells that are actively absorbing materials. They increased the surface area through which materials are absorbed Dec 8­1:18 PM Dec 8­1:19 PM 3 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Mitochondrion Large organelles shaped like jelly beans scattered through most cells. A cross sectional view of a mitochondrion shows two membranes. The inner membrane is folded to increase the surface area for chemical reactions. The function of the mitochondria is to produce energy rich molecules of ATP using energy obtained by the breakdown of fuel molecules such as glucose. Dec 8­1:19 PM Dec 8­1:19 PM 4 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Ribosomes Small spherical organelles found free in the cytoplasm or attached to the endoplasmic reticulum. Ribosomes are the sites of protein synthesis. Following the directions of DNA and with the help of mRNA and tRNA, these protein factories make proteins to be used by the cell or to be exported out of the cell. Dec 8­1:19 PM Dec 8­1:19 PM 5 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Endoplasmic Reticulum A system of double membranes that connect the nucleus to the cell membrane. Some have ribosomes on the surface and are called rough ER, those without are called smooth ER. The general function of ER is to transport materials through the cytoplasm. Dec 8­1:19 PM Dec 8­1:19 PM 6 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Golgi Apparatus The golgi apparatus appears as a stack of membrane sacs. It receives molecules of protein from the endoplasmic reticulum. Acting as a protein packaging factory, the golgi apparatus wraps up protein molecules into a single membranous envelope or vesicle. The final product enclosed in the vesicle is sent through the cell membrane. This is how the cell secretes their hormones, enzymes or other types of cell products. Dec 8­1:19 PM Dec 8­1:19 PM 7 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Vacuole A membrane bound sac. Serves to store food and waste materials Fluid Food Dec 8­1:19 PM Dec 8­2:35 PM 8 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Lysosome Small organelles scattered throughout the cytoplasm. Lysosomes are both the cell's digestive system and recycling center. They contain chemicals that digest, or break down, small particles of food that enter the cell. They also digest worn out parts of the cell, so the raw materials can be used again. Dec 8­1:19 PM Dec 8­1:19 PM 9 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Dec 8­1:19 PM Microtubules Long thin hollow tubes of proteins. Microtubules are found in the cell's cytoskeleton, giving the cytoplasm strength and shape. They also help in cell movement as the structural unit of cells’ centrioles, flagella and cilia Dec 8­1:19 PM 10 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Centrioles Found in most animal cells. They are made of a stack of microtubules similar to soda straws. During cell division they make up part of the spindle that divides the chromosomes between the two daughter cells Dec 8­1:19 PM Dec 8­1:19 PM 11 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Cilia and Flagella Hair­like extensions of the cell Cilia tend to be shorter than flagella and work in groups. Each flagellum is larger and usually acts individually. Both cilia and flagella are involved in cell locomotion and transport Dec 8­1:19 PM https://www.youtube.com/watch?v=QGAm6hMysTA Dec 8­1:19 PM 12 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Special Structures of Plant Cells Vacuole Membrane bond sacs Storage sites within a cell. In plant cells the vacuoles are much larger than in animal cells. When a cell has stopped growing there is usually one very large vacuole. Sometimes that vacuole can take up more than half of the cell's volume. The vacuole holds large amounts of water or food. The vacuoles can also hold the plant waste products. Dec 8­1:19 PM Dec 8­1:19 PM 13 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Chloroplasts Large organelles containing the green pigment chlorophyll. The function of chloroplasts is to trap light energy for the process photosynthesis. They help the plant to make sugar from simple raw materials like carbon dioxide and water. Dec 8­1:19 PM Dec 8­1:19 PM 14 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Cell Wall Surrounds most plant cells. Made of a complex carbohydrate called cellulose. This nonliving structure both protects and supports the cell. Cell Wall Dec 8­1:19 PM Dec 8­1:19 PM 15 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Dec 8­1:19 PM Do Now Problems: 1. Write the chemical formula for each of the following: Silver oxide Cobalt (II) sulphide dinitrogen trichloride May 13­8:12 AM 16 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 1,3, 5­7, 9­14 May 13­8:16 AM May 13­8:17 AM 17 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 The Cell Nucleus The nucleus is a highly specialized organelle that serves as the information processing and administrative center of the cell. This organelle has two major functions: it stores the cell's hereditary material, or DNA, and it coordinates the cell's activities, which include growth, intermediary metabolism, protein synthesis, and reproduction (cell division). Dec 7­9:08 AM Only the cells of advanced organisms, known as eukaryotes, have a nucleus. Simpler one­celled organisms (prokaryotes), like the bacteria and cyanobacteria, don't have a nucleus. In these organisms, all of the cell's information and administrative functions are dispersed throughout the cytoplasm. Dec 12­8:28 AM 18 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 The spherical nucleus typically occupies about 10 percent of a eukaryotic cell's volume, making it one of the cell's most prominent features. A double­layered membrane, the nuclear envelope, separates the contents of the nucleus from the cellular cytoplasm. The envelope is riddled with holes called nuclear pores that allow specific types and sizes of molecules to pass back and forth between the nucleus and the cytoplasm. It is also attached to a network of tubules and sacs, called the endoplasmic reticulum, where protein synthesis occurs, and is usually studded with ribosomes (see Figure 1). Dec 12­8:28 AM The semifluid matrix found inside the nucleus is called nucleoplasm. Within the nucleoplasm, most of the nuclear material consists of chromatin, the less condensed form of the cell's DNA that organizes to form chromosomes during mitosis or cell division. Dec 12­8:31 AM 19 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Chromatin and Chromosomes ­ Packed inside the nucleus of every human cell is nearly 6 feet of DNA, which is divided into 46 individual molecules, one for each chromosome and each about 38 mm long. Packing all this material into a microscopic cell nucleus is an extraordinary feat of packaging. For DNA to function, it can't be crammed into the nucleus like a ball of string. Instead, it is combined with proteins and organized into a precise, compact structure, a dense string­like fiber called chromatin. Dec 12­9:30 AM The Nucleolus ­ The nucleolus is a membrane­less organelle within the nucleus that manufactures ribosomes, the cell's protein­ producing structures. Through the microscope, the nucleolus looks like a large dark spot within the nucleus. During cell division, the nucleolus disappears. Some studies suggest that the nucleolus may be involved with cellular aging and, therefore, may affect the senescence of an organism. Dec 12­9:31 AM 20 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 The Nuclear Envelope ­ The nuclear envelope is a double­layered membrane that encloses the contents of the nucleus during most of the cell's lifecycle. The envelope is perforated with tiny holes called nuclear pores. These pores regulate the passage of molecules between the nucleus and cytoplasm, permitting some to pass through the membrane, but not others. During mitosis, or cell division, the nuclear envelope disintegrates, but reforms as the two cells complete their formation and the chromatin begins to unravel and disperse. Dec 12­9:32 AM Nuclear Pores ­ The nuclear envelope is perforated with holes called nuclear pores. These pores regulate the passage of molecules between the nucleus and cytoplasm, permitting some to pass through the membrane, but not others. Building blocks for building DNA and RNA are allowed into the nucleus as well as molecules that provide the energy for constructing genetic material. Dec 12­9:33 AM 21 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 Component Description of Structure Function Nucleolus Nucleoplasm Nuclear envelope Nuclear pores Chromosomes/Chromatin Dec 12­9:34 AM http://www.youtube.com/watch?v=rABKB5aS2Zg Homework: Pg. 284 Questions 1,2,5-9 Dec 12­9:41 AM 22 Topic 1d Cell Structure and Organelles(1).notebook December 09, 2015 http://www.youtube.com/watch?v=PrX3h­AflZI http://www.youtube.com/watch?v=i2x3MKSJez4 May 15­3:27 PM 23