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  • 7/30/2019 Cells,Tissues,Organs,System Gab



    1. (fromLatin:scientia, meaning "knowledge") is a systematic enterprise of gathering

    knowledge about the world and organizing and condensing that knowledge into testable laws

    and theories

    2. According to Webster's New Collegiate Dictionary, the definition of science is"knowledge attained through study or practice," or "knowledge covering general truths of the

    operation of general laws, esp. as obtained and tested through scientific method [and]

    concerned with the physical world."

    3. Science refers to a system of acquiring knowledge. This system uses observation and

    experimentation to describe and explain natural phenomena. The term science also refers to

    the organized body of knowledge people have gained using that system. Less formally, the

    word science often describes any systematic field of study or the knowledge gained from it.

    What is the purpose of science? Perhaps the most general description is that the purpose of

    science is to produce useful models of reality.


    Training Guide prepared by Karen L. Lancour, National Supervisor

    This event is a lab-oriented competition involving the fundamental science processes of a

    middle school life-science program. The event is not meant to be a comprehensive biology

    course. If specific content is needed when students are being tested on certain process skills,

    the supervisor will provide that content.


    The event consists of a series of biological questions or tasks that involve the use of one ormore process skills. Science process skills are classified as basic skills and integrated skills.

    These skills can be accessed by applying them to a series of lab station activities which are

    included in the Guide for Supervisors, Coaches and Students. Tips to assist students in their

    preparations are also included in this guide.

    Basic Science Process Skills:

    Observing - using your senses to gather information about an object or event. It is a

    description of

    what was actually perceived. This information is considered qualitative data. Measuring - using standard measures or estimations to describe specific dimensions of an

    object or event. This information is considered quantitative data.

    Inferring - formulating assumptions or possible explanations based upon observations.

    Classifying - grouping or ordering objects or events into categories based upon

    characteristics or defined criteria.

    Predicting - guessing the most likely outcome of a future event based upon a pattern of


    Communicating - using words, symbols, or graphics to describe an object, action or event.

    Integrated Science Process Skills:

    Formulating Hypotheses - stating the proposed solutions or expected outcomes for


    These proposed solutions to a problem must be testable.

    Identifying of Variables - stating the changeable factors that can affect an experiment. It is


    to change only the variable being tested and keep the rest constant. The one being

    manipulated is the independent variable; the one being measured to determine its response is

  • 7/30/2019 Cells,Tissues,Organs,System Gab


    the dependent variable; and all variables that do not change and may be potential

    independent variables are constants.

    Defining Variables Operationally - explaining how to measure a variable in an experiment.

    Describing Relationships Between Variables - explain relationships between variables in an

    experiment such as between the independent and dependant variables plus the standard ofcomparison.

    Designing Investigations - designing an experiment by identifying materials and describing

    appropriate steps in a procedure to test a hypothesis.

    Experimenting - carrying out an experiment by carefully following directions of the

    procedure so the results can be verified by repeating the procedure several times.

    Acquiring Data - collecting qualitative and quantitative data as observations and


    Organizing Data in Tables and Graphs - making data tables and graphs for data collected.

    Analyzing Investigations and Their Data - interpreting data statistically, identifying human


    and experimental errors, evaluating the hypothesis, formulating conclusions, and

    recommending further testing where necessary.

    Understanding Cause and Effect Relationships - what caused what to happen and why.

    Formulating Models - recognizing patterns in data and making comparisons to familiar

    objects or ideas.


    The cell is the functional basic unit of life. It was discovered by Robert Hookeand is the

    functional unit of all known livingorganisms. It is the smallest unit of life that is classified as

    a living thing, and is often called the building block of life. Some organisms, such as most

    bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are

    multicellular. (Humans have about 100 trillion or 1014 cells; a typical cell size is 10m; a

    typical cell mass is 1nanogram. The largest cells are about 135 m in theanterior horn in

    the spinal cordwhilegranule cellsin thecerebellum, the smallest, can be some 4 m and the

  • 7/30/2019 Cells,Tissues,Organs,System Gab


    longest cell can reach from the toe to the lowerbrain stem(Pseudounipolar cells).[2]) The

    largest known cells are unfertilisedostrichegg cellswhich weigh 3.3 pounds

    In 1835, before the final cell theory was developed,Jan Evangelista Purkynobserved small

    "granules" while looking at the plant tissue through a microscope. The cell theory, first

    developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that allorganisms are composed of one or more cells, that all cells come from preexisting cells, that

    vital functions of an organism occur within cells, and that all cells contain the hereditary

    informationnecessary for regulating cell functions and for transmitting information to the

    next generation of cells.

    The word cellcomes from theLatincellula, meaning, a small room. The descriptive term for

    the smallest living biological structure was coined byRobert Hookein a book he published in

    1665 when he compared thecorkcells he saw through his microscope to the small rooms

    monks lived in.

    The cell is one of the most basic units of life. There are millions of different types of cells.

    There are cells that are organisms onto themselves, such as microscopic amoeba and bacteria

    cells. And there are cells that only function when part of a larger organism, such as the cells

    that make up your body. The cell is the smallest unit of life in our bodies. In the body, there

    are brain cells, skin cells, liver cells, stomach cells, and the list goes on. All of these cells have

    unique functions and features. And all have some recognizable similarities. All cells have a

    'skin', called the plasma membrane, protecting it from the outside environment. The cell

    membrane regulates the movement of water, nutrients and wastes into and out of the cell.

    Inside of the cell membrane are the working parts of the cell. At the center of the cell is thecell nucleus. The cell nucleus contains the cell'sDNA, the genetic code that coordinates protein

    synthesis. In addition to the nucleus, there are many organelles inside of the cell - small

    structures that help carry out the day-to-day operations of the cell. One important cellular

    organelle is the ribosome. Ribosomes participate in protein synthesis. Thetranscriptionphase

    of protein synthesis takes places in the cell nucleus. After this step is complete, the mRNA

    leaves the nucleus and travels to the cell's ribosomes, where translation occurs. Another

    important cellular organelle is the mitochondrion. Mitochondria (many mitochondrion) are

    often referred to as the power plants of the cell because many of the reactions that produce

    energy take place in mitochondria. Also important in the life of a cell are the lysosomes.Lysosomes are organelles that contain enzymes that aid in the digestion of nutrient molecules

    and other materials. Below is a labelled diagram of a cell to help you identify some of these