Zoology Unit 4.1 Tissues PDF

Zoology ZOOLOGY Zoology UNIT 4: Multicellular Organization Zoology OBJECTIVES At the end of this unit, you will be able to: a. Name the four major tissues types and their subcategories; b. Give the chief locations of the various tissue ty...

Zoology ZOOLOGY Zoology UNIT 4: Multicellular Organization Zoology OBJECTIVES At the end of this unit, you will be able to: a. Name the four major tissues types and their subcategories; b. Give the chief locations of the various tissue types in the body; and, c. Describe the process of tissue repair. Zoology ∙ Lesson 4. 1 : Tissues o Epithelial Tissue o Connective Tissue o Muscular Tissue o Nervous Tissue ∙ Lesson 4. 2. Organs and Systems ∙ Lesson 4.3. Body Plan and Multicellular Animals Zoology There are five grades of organization that can be recognized in animals: ∙ (1) Protoplasm, ∙ (2) Cell, ∙ (3) Tissue, ∙ (4) Organ, and ∙ (5) Organ System. Zoology A tissue is a group of similar cells, usually with a common embryonic origin, that function together to carry out specialized activities. A pathologist (pa-THOL-o ̄ -gist; patho- disease) is a physician who specializes in laboratory studies of cells and tissues to help other physicians make accurate diagnoses. One of the principal functions of a pathologist is to examine tissues for any changes that might indicate disease. Zoology Histology (hiss-TOL-o ̄ -je ̄ ; hist- tissue; -logy study of) is the science that deals with the study of tissues. Zoology Zoology A biopsy is a medical procedure that involves removing a small sample of tissue or cells from the body to examine under a microscope. Excisional Biopsy.mp4 Breast Needle Biopsy Procedure Patient Education Surgery.mp4 Zoology TYPES OF TISSUES Body tissues are classified into four basic types based on their structure and functions: 1.Epithelial tissue (ep-i-THE -le ̄ -al) covers body surfaces; lines body cavities, hollow organs, and ducts (LINING); and forms glands (GLANDULAR). 2.Connective tissue protects and supports the body and its organs, binds organs together, stores energy reserves as fat, and provides immunity. 3.Muscular tissue generates the physical force needed to make body structures move. 4.Nervous tissue detects changes inside and outside the body and initiates and transmits nerve impulses (action potentials) that coordinate body activities to help maintain homeostasis. Zoology Zoology Epithelial Cells 1. Apical (free) Surface - most superficial layer of cells - exposed to body cavity, lining of an internal organ, or exterior of the body 1. Lateral Surface - face adjacent cells on either side 1. Basal Surface - attached to the basement membrane - deepest layer of cells Basement Membrane - extracellular structure composed mostly of protein fibers - located between epithelium and underlying connective tissue - helps bind and support epithelium Zoology Epithelial Cells Zoology Why is epithelium subject to a certain amount of tear and injury? Zoology It has the capacity for renewal or repair by cell division. Zoology Epithelial tissue Zoology Epithelial tissue Zoology Epithelial tissue ❖Squamous cells – flattened like fish scales ❖Cuboidal cells – cube-shaped like dice ❖Columnar cells – shaped like columns Zoology Simple Squamous - Single layer of thin squamous cells - transport Found in: - Air sacs of lungs - Walls of capillaries Zoology Simple Cuboidal - Single layer of thin cuboidal cells - secretion and absorption Commonly found in: - Glands and ducts (salivary and pancreas) - Walls of kidney tubules - Covering of ovaries Zoology Simple Columnar - Single layer of thin columnar cells/tall cells that fit closely together - secretion Commonly found in: - Goblet cells (produces lubricating mucus: conjunctiva) - Lining of entire digestive tract from stomach to anus Zoology Stratified Squamous - Most common stratified - Consists of multiple layers - protection Commonly found in: - Sites that receive a good deal of friction (esophagus, mouth, outer skin) Zoology Stratified Cuboidal - Two cell layers with (at least) the surface of cells being a cuboidal shape - Rare in the body - Protection and secretion of glands Commonly found in: - Ducts of large glands (excretory ducts of salivary and sweat glands) Zoology Stratified Columnar - Columnar cell, but its basal cells vary in size and shape - Protection and secretion of glands Commonly found in: - Ducts of large glands - Mucous membrane (conjunctiva) Zoology Transitional Epithelium - As the cells are stretched, they become flatter, giving the appearance of stratified squamous epithelium. - Lines hollow structures that are subjected to expansion from within due to its elasticity - It allows organs to stretch to hold a variable amount of fluid without rupturing (urinary bladder) Zoology Glandular Epithelium - Secretion accomplished by glandular cells that often lie in clusters deep to the covering and lining epithelium - A gland may consist of one cell or a group of highly specialized epithelial cells that secrete substances into ducts (tubes), onto a surface, or into the blood. Zoology Connective Tissue ❖Connects body parts ❖Found everywhere in the body ❖Most abundant and widely distributed of the tissue types. ❖Functions: protecting, supporting, and binding together other body tissues. Zoology Connective Tissue Common Characteristics ❖ Variations of blood supply - Tendons and ligaments have poor blood supply ❖ Extracellular Matrix - surround, support, and give structure to cells and tissues in the body Zoology Connective Tissue 1.Bone 2. Cartilage 3.Dense connective tissues 4.Loose connective tissues 5. Areolar tissue 6. Adipose tissue 7. Reticular connective tissue 8. Blood or vascular Zoology Connective Tissue Bone - Called osseous tissue - Composed of bone cells (osteocytes) sitting in cavities (lacunae) Zoology Connective Tissue Cartilage - Less hard and more flexible than the bone - Most widespread: hyaline Hyaline Cartilage - has abundant collagen fibers hidden by rubbery matrix Other types: fibrocartilage, elastic cartilage Zoology Connective Tissue Dense Connective - Dense fibrous tissue - Has collagen fibers as its matrix element - Forms a strong, rope-like structure - (tendons and ligaments) Zoology Connective Tissue Loose Connective - Softer and have more cells - Found around blood vessels - Fewer fibers than other types except blood - A category that includes: areolar, adipose, reticular Zoology Loose Connective Tissue Areolar - Soft, pliable, “cobwebby” - Cushions and protects organs it wraps - Universal packing tissue - Connective tissue glue - Soft layer: lamina propria Zoology Loose Connective Tissue Adipose - Commonly called “fat” - Fat cells predominate - Forms subcutaneous tissue beneath skin - Insulates body & protect from extremes of heat & cold Zoology Loose Connective Tissue Reticular - Consists of delicate network of interwoven reticular fibers with reticular cells (fibroblasts) - Forms stroma - bed or mattress - supports many free blood cells in lymphoid organs: nodes, spleen, bone marrow Zoology Connective Tissue Vascular/Blood - Consists of blood cells - Surrounded by non-living, fluid matrix (blood plasma) - the transport vehicle for the cardiovascular system Zoology Muscular Tissue ❖Highly specialized to contract or shorten, to produce movement. ❖Consists of elongated cells called muscle fibers that are highly specialized to generate force. ❖Produces motion, maintains posture, and generates heat. ❖Protection Zoology Zoology Zoology TYPES OF MUSCLE TISSUE 1. Skeletal muscle tissue - usually attached to the bones of the skeleton. - consists of thousands of muscle fibers wrapped together by connective tissue sheaths. Zoology TYPES OF MUSCLE TISSUE 2. Cardiac muscle tissue - forms the bulk of the wall of the heart (myocardium). - Cardiac muscle cells appear striated or striped under a microscope. Zoology TYPES OF MUSCLE TISSUE 3. Smooth muscle tissue - located in the walls of hollow internal structures (blood vessels, airways to the lungs, the stomach, intestines) - consists of thick and thin filaments that are not arranged into sarcomeres giving it a non-striated pattern Zoology Muscular Tissue Zoology NERVOUS TISSUE ❖ it consists of only two principal types of cells: neurons and neuroglia. ❖ Neurons (neur- nerve, nerve tissue, nervous system) or nerve cells, are sensitive to various stimuli. They convert stimuli into nerve impulses (action potentials) and conduct these impulses to other neurons, to muscle fibers, or to glands. ❖ Neuroglia (noo-ROG-le ̄ -a; -glia glue) do not generate or conduct nerve impulses, but they do have many other important supportive functions. Zoology ∙ Tissue repair is the process that replaces worn-out, damaged, or dead cells. New cells originate by cell division from the stroma, the supporting connective tissue, or from the parenchyma (tissue layers that help function of organs or tissue) Zoology ∙ Inflammation – a generalized (nonspecific) body response that attempts to prevent further injury. ∙ Immune response -extremely specific and mounts a vigorous attack against recognized invaders (bacteria, viruses, toxins) Zoology Tissue repair occurs in two major ways: by regeneration and by fibrosis. ∙ Regeneration – replacement of destroyed tissue by the same kind of cells ∙ Fibrosis – involves repair by dense connective tissue, formation of scar tissues. Zoology Regeneration Fibrosis Zoology References: Chanco, C. R. General Zoology. 2nd Edition. Pasay City, Philippines, 2012. Marieb, E.N. Essentials of Human Anatomy and Physiology, 8th edition Marieb, E.N. Essentials of Human Anatomy and Physiology Laboratory Manual, 3rd edition Marieb, E.N. Essentials of Human Anatomy and Physiology Coloring Workbook, 8th edition Tortora, G.J. Introduction to the Human Body (anatomy and physiology, 8th edition) https://rsscience.com/wp-content/uploads/2022/04/classify-epithelial-tissue-shape- 1024x768.jpg?ezimgfmt=rs:361x271/rscb1/ng:webp/ngcb1 Zoology Prepared by : Mireille Joy Cayabo & Shulamith Sevilla