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Plots, orders, and compares, using <, >, =, rational and irrational numbers represented in various forms: ➢ includes roots with the same index (L3) ➢ includes at least one square root and one cube root (L4)
Multi Step Equations
Algebra Study Tool #1
The cytoskeleton is a network of thin tubes and filaments that crisscrosses the cytosol. The tubes and filaments give shape to the cell from the inside in the same way that tent poles support the shape of a tent. The cytoskeleton also acts as a system of internal tracks, shown in Figure 4-18, on which items move around inside the cell. The cytoskeleton’s functions are based on several struc- tural elements. Three of these are microtubules, microfilaments, and intermediate filaments, shown and described in Table 4-2. Microtubules Microtubules are hollow tubes made of a protein called tubulin. Each tubulin molecule consists of two slightly different subunits. Microtubules radiate outward from a central point called the centrosome near the nucleus. Microtubules hold organelles in place, maintain a cell’s shape, and act as tracks that guide organelles and molecules as they move within the cell. Microfilaments Finer than microtubules, microfilaments are long threads of the beadlike protein actin and are linked end to end and wrapped around each other like two strands of a rope. Microfilaments con- tribute to cell movement, including the crawling of white blood cells and the contraction of muscle cells. Intermediate Filaments Intermediate filaments are rods that anchor the nucleus and some other organelles to their places in the cell. They maintain the inter- nal shape of the nucleus. Hair-follicle cells produce large quantities of intermediate filament proteins. These proteins make up most of the hair shaft. 84 CHAPTER 4 TABLE 4-2 The Structure of the Cytoskeleton Property Microtubules Microfilaments Intermediate filaments Structure hollow tubes made of two strands of intertwined protein fibers coiled into coiled protein protein cables Protein subunits tubulin, with two subunits: å actin one of several types of and ∫ tubulin fibrous proteins Main function maintenance of cell shape; cell maintenance and changing of maintenance of cell shape; motility (in cilia and flagella); cell shape; muscle contraction; anchor nucleus and other chromosome movement; movement of cytoplasm; cell organelles; maintenance of organelle movement motility; cell division shape of nucleus Shape Microtubules provide a path for organelles and molecules as they move throughout the cell. FIGURE 4-18 Microtubules Nucleus Endoplasmic reticulum Mitochondrion Ribosomes Copyright © by Holt, Rinehart and Winston. All rights reserved. Copyright © by Holt, Rinehart and Winston. All rights reserved. CELL STRUCTURE AND FUNCTION 85 1. Explain how the fluid mosaic model describes the plasma membrane. 2. List three cellular functions that occur in the nucleus. 3. Describe the organelles that are found in a eukaryotic cell. 4. Identify two characteristics that make mitochon- dria different from other organelles. 5. Contrast three types of cytoskeletal fibers. CRITICAL THINKING 6. Relating Concepts If a cell has a high energy requirement, would you expect the cell to have many mitochondria or few mitochondria? Why? 7. Analyzing Information How do scientists think that mitochondria originated? Why? 8. Analyzing Statements It is not completely accurate to say that organelles are floating freely in the cytosol. Why not? SECTION 3 REVIEW During cell division, centrioles organize microtubules that pull the chromosomes (orange) apart. The centrioles are at the center of rays of microtubules, which have been stained green with a fluorescent dye. FIGURE 4-20 Cilia and Flagella Cilia (SIL-ee-uh) and flagella (fluh-JEL-uh) are hairlike structures that extend from the surface of the cell, where they assist in movement. Cilia are short and are present in large numbers on certain cells, whereas flagella are longer and are far less numerous on the cells where they occur. Cilia and flagella have a membrane on their outer surface and an internal structure of nine pairs of micro- tubules around two central tubules, as Figure 4-19 shows. Cilia on cells in the inner ear vibrate and help detect sound. Cilia cover the surfaces of many protists and “row” the protists through water like thousands of oars. On other protists, cilia sweep water and food particles into a mouthlike opening. Many kinds of protists use flagella to propel themselves, as do human sperm cells. Centrioles Centrioles consist of two short cylinders of microtubules at right angles to each other and are situated in the cytoplasm near the nuclear envelope. Centrioles occur in animal cells, where they organize the microtubules of the cytoskeleton during cell division, as shown in Figure 4-20. Plant cells lack centrioles. Basal bodies have the same structure that centrioles do. Basal bodies are found at the base of cilia and flagella and appear to organize the devel- opment of cilia and flagella.
Create a mcq questions based on the following learning objectives identify and state the functions of the following cell structures (including organelles) of typical plant and animal cells from diagrams, light micrographs and as seen under the light microscope using prepared slides and fresh material treated with an appropriate temporary staining technique, identify and state the functions of the following organelles from diagrams and electron micrographs: • mitochondria • ribosomes
Term of Appointment and Role of Secretary-General of ASEAN based on Article 11 of the ASEAN Charter: The Secretary-General of ASEAN shall be appointed by the ASEAN Summit for a non-renewable term of office of five years, selected from among nationals of the ASEAN Member States based on alphabetical rotation, with due consideration to integrity, capability and professional experience, and gender equality. The Secretary-General shall: carry out the duties and responsibilities of this high office in accordance with the provisions of this Charter and relevant ASEAN instruments, protocols and established practices; facilitate and monitor progress in the implementation of ASEAN agreements and decisions, and submit an annual report on the work of ASEAN to the ASEAN Summit; participate in meetings of the ASEAN Summit, the ASEAN Community Councils, the ASEAN Coordinating Council, and ASEAN Sectoral Ministerial Bodies and other relevant ASEAN meetings; present the views of ASEAN and participate in meetings with external parties in accordance with approved policy guidelines and mandate given to the Secretary-General; and recommend the appointment and termination of the Deputy Secretaries-General to the ASEAN Coordinating Council for approval. The Secretary-General shall also be the Chief Administrative Officer of ASEAN. The Secretary-General shall be assisted by four Deputy Secretaries-General with the rank and status of Deputy Ministers. The Deputy Secretaries-General shall be accountable to the Secretary-General in carrying out their functions. The four Deputy Secretaries-General shall be of different nationalities from the Secretary-General and shall come from four different ASEAN Member States. The four Deputy Secretaries-General shall comprise: two Deputy Secretaries-General who will serve a non-renewable term of three years, selected from among nationals of the ASEAN Member States based on alphabetical rotation, with due consideration to integrity, qualifications, competence, experience and gender equality; and two Deputy Secretaries-General who will serve a term of three years, which may be renewed for another three years. These two Deputy Secretaries-General shall be openly recruited based on merit. The ASEAN Secretariat shall comprise the Secretary-General and such staff as may be required. The Secretary-General and the staff shall: uphold the highest standards of integrity, efficiency, and competence in the performance of their duties; not seek or receive instructions from any government or external party outside of ASEAN; and refrain from any action which might reflect on their position as ASEAN Secretariat officials responsible only to ASEAN. Each ASEAN Member State undertakes to respect the exclusively ASEAN character of the responsibilities of the Secretary-General and the staff, and not to seek to influence them in the discharge of their responsibilities.
Life Processes Identify and define the seven life processes (MRS GREN). Classification Group living organisms based on observed similarities and differences. Classify vertebrates into taxonomic groups based on visible physical characteristics. Construct a dichotomous key to classify vertebrates. Cells Compare the structure of generalised plant and animal cells, and selected microbes (e.g. bacteria, fungi and Amoeba) Distinguish among cell wall, cell membrane, nucleus, cytoplasm, temporary and permanent vacuoles, mitochondrion, chloroplast, endoplasmic reticulum and ribosomes. Relate the structure of organelles to their functions; Identify specialised cells such as blood cells, ciliated epithelial cells, nerve cells, root hair cells, sperm cells and egg cells. Explain the importance of cell specialisation in multicellular organisms; include hierarchy of cells, tissues, organs; organ systems and then organism Diffusion, Osmosis, Active transport and Osmoregulation Explain the processes of diffusion, osmosis and active transport. Identify everyday instances of these processes occurring. Discuss the importance of diffusion, osmosis and active transport in living systems. Nutrition in Plants Describe the process of photosynthesis in green plants; test for end products, starch or reducing sugar (glucose). Relate the structure of the leaf of a flowering plant to its function in photosynthesis; draw and label the external features and the internal structure (cross section) of a leaf as seen in cross section under the light microscope. Nutrition in Humans Discuss the importance of a balanced diet in humans. State components of a balanced diet (carbohydrates, fats, proteins, vitamins and minerals, water and roughage and their roles) along with the results of their deficiency or surplus. Suggest dietary recommendations for treating and preventing named deficiency and physiological diseases (such as those outlined in the manual and your notes). Perform tests to distinguish among food substances - Test for proteins (Biuret), fats (grease spot), starch (iodine), reducing sugars (Benedict’s solution). The Digestive System in Humans Relate the structures of the human alimentary canal to their functions; Draw and label simple diagrams of the alimentary canal and internal structure of a tooth required. Describe mastication and the role of teeth in the mechanical breakdown of food to be included. (Compare types of teeth in humans and compare types of teeth in herbivores and carnivores.) Explain the role and importance of enzymes role of digestive enzymes in the mouth, stomach and pancreatic enzymes in the small intestine. Discuss properties of enzymes. Deduce from tables and graphs the effects of temperature and pH on enzyme activity. Experimental Skills Follow all drawing rules as outlined in the drawing skills checklist posted in the classroom (including calculation of magnification).
A router is a networking device that
forwards data packets between
computer networks. Routers perform
the traffic directing functions
between networks and on the global
Internet. Data sent through a
network, such as a web page or
email, is in the form of data packets.
a firewall is a network security
system that monitors and controls
incoming and outgoing network
traffic based on predetermined
security rules. A firewall typically
establishes a barrier between a
trusted network and an untrusted
network, such as the Internet.
A modem is a network device that
both modulates and demodulates
analog carrier signals (called sine
waves) for encoding and decoding
digital information for processing.
A hub is a physical layer networking
device which is used to connect
multiple devices in a network.