Levels of Organization in Multi-Cellular Organisms PDF

4/16/2024 Discussion Levels of Organization in Multi-cellular 1. Which level is the lowest and the simplest?...

4/16/2024 Discussion Levels of Organization in Multi-cellular 1. Which level is the lowest and the simplest? Organism Why? 2. Why is the organ more complex than the tissue? 3. Rearrange the following from the lowest level to the highest level. a. brain, nerve, nervous system, neuron, bird Cell Tissue Organ Organ system Organism b. Tree, leaf, mesophyll cell, phloem, shoot system 4. How do these levels of organisation help an 1 organism survive? 2 Cell Types of Tissue Cell is the structural and functional unit of living Plant Tissue Animal Tissue organism. Meristematic tissue Epithelial Tissue Permanent tissues Connective Tissue Tissue Muscle Tissue Simple permanent tissues Complex permanent tissues Nervous Tissue Tissue are the group of similar cells that perform Parenchyma specific function. Xylem Collenchyma Sclerenchyma Phloem 3 4 Epithelial Tissue Can we find tissue in unicellular organism? Epithelial Tissue covers the surface of the body (skin) and lines the internal organs and cavities of the body such as mouth, nose, stomach, lungs, blood vessels, etc. Animal Tissue Epithelial cells may be flat, cuboidal, or columnar in shape. classified into four categories: The tissue is mainly responsible for protection epithelial tissue, connective tissue, muscular tissue and nervous tissue against injury and germs, and helps in absorption, secretion, and sensation. 5 6 1  4/16/2024 Connective Tissue Connective Tissue is also known as supportive tissue. It binds one tissue to another, and connects various organs. Examples of connective tissue are blood, bone, cartilage, ligament and tendons. This tissue also provides protection to various parts of the animal body. 7 8 Muscle Tissue Muscle Tissue forms the muscles of the body. It consists of a special type of cells, which has the ability to contract and relax. It helps the body in its movement. Muscle tissues are of three types: cardiac, striated, and non-striated. 9 10 Nervous Tissue Nervous Tissue is made up of highly specialized cells called neurons. They transmit messages from all parts of the body to the brain and the spinal cord, and vice versa. 11 12 2  4/16/2024 The part of neuron containing nucleus is called Neurone cell body. Many long cytoplasmic projections called dendrites arise from the cell body. One of the dendrites is long and is called axon. The dendrites carry messages towards the cell body, and the axon carries messages away from the cell body. 13 14 Meristematic tissue It is found at all growing points of a plant, such as tips of roots, stems and branches. Plant Tissue It is also present in between the bark and the wood of trees. Plant tissues are basically of two types: It multiplies and brings about the growth of meristematic tissue and permanent tissue. plants. Meristematic tissue Root cap 15 16 Permanent tissues Simple permanent tissues They are made up of either living or dead cells, 1. Parenchyma which have lost their ability to multiply. They are the living cells with thin cell walls and there are spaces between the cells. They have permanent shapes. It consists of oval, spherical, or polygonal cells They are found in soft parts of plants such as Permanent tissues are of two types: in the central part of roots and stems. - simple permanent tissue and The functions of these tissues are to store - complex permanent tissue. food and water, and also provide temporary support to the plant. 17 18 3  4/16/2024 2. Collenchyma 3. Sclerenchyma They are living cells with thick cell walls They are dead cells with thick cell walls that without spaces between them. are closely packed. They may be circular, oval or polygonal in The cells of this tissue are elongated and have shape pointed ends or polygonal in shape It is mostly found in non-woody plants, leaf It is found in stems and veins of leaves. stalks, and veins of leaves. It provides strength and protection to the It provides support and flexibility to the plant. plant. 19 20 Complex permanent tissues It consist of two conducting tissues: Xylem and Phloem, which together form the vascular bundle. 21 22 Xylem It transports water and dissolved minerals from the roots to the other parts of the plant. Phloem It transports food from the leaves to different parts of the plant. 23 24 4  4/16/2024 Activity Organ Identify two differences between meristematic and permanent tissues. An organ is a group of tissues working Is xylem similar to blood vessels found in humans? together to perform a common function. How? For example, heart is an organ, which has Complete the table. lining of epithelial tissue, muscular tissue, nerve tissue and connective tissue. All these tissues work together to pump the blood. Other examples of organs are lungs, kidneys, 25 skin, etc 26 Organ System An organ system is a group of organs which work together to carry out a specific function. The human body is made up of different organ systems as shown in Figure 27 28 Organism Questions 1. Differentiate the following pairs: An individual, such as an animal, a plant, or even a a. Cell and tissue. microorganism that reproduce, grow, respire, etc. b. Organ and organ system. is known as organism. c. Xylem and phloem. Multicellular organisms have organs and organ systems. 2. Classify the following structures into cell, tissue, organ, organ system, and organism. Structures: neuron, blood, egg, leaf, bone, Each organ system coordinates with other organ flower, bacteria, mushroom, bear, eye, human systems to perform life processes such as skeleton, and parenchyma. digestion, respiration, excretion, etc. 29 30 5