BIO122: Chapter 7 | Tissues

CHAPTER 7: TISSUES (PART 1)

Prepared by: Madam Saiyidah Nafisah Hashim
Faculty of Applied Sciences, UITM Perak Branch, Tapah Campus

SYLLABUS CONTENT

  • 7.1 ANIMAL TISSUES

    • Epithelium

    • Connective

    • Muscle

    • Nervous Tissues

  • 7.2 PLANT TISSUES

    • Meristematic

    • Dermal

    • Ground

    • Vascular

LESSON OUTCOMES

  • State & define terminologies in tissues.

  • Identify, draw, label & describe the characteristics of animal & plant tissues.

  • At the end of the lessons students should be able to:

    • Understand the fundamental types and roles of tissues.

TISSUES

A. ANIMAL TISSUES

  • Epithelial

    • Characteristics: Shape, Thickness

  • Connective

    • Loose Connective Tissue

    • Fibrous Connective Tissues

    • Adipose tissue

    • Bone

    • Hyaline cartilage

    • Blood

  • Muscle

    • Skeletal

    • Smooth

    • Cardiac

  • Nervous

    • Sensory neuron

    • Interneuron

    • Motor neuron

B. PLANT TISSUES

  • Meristem

    • Apical

    • Lateral

  • Ground

    • Parenchyma

    • Collenchyma

    • Sclerenchyma

  • Vascular

    • Xylem

    • Phloem

  • Dermal

    • Epidermis

    • Bark

WHAT IS ANATOMY?

  • ANATOMY:

    • Study of the structure of organisms, focusing on cells and tissues.

    • Morphology: Study of form.

WHAT IS PHYSIOLOGY?

  • PHYSIOLOGY:

    • Study of the function of cells, tissues, organs of living things.

    • Concerns the physics/chemistry of these functions.

ANATOMY, MORPHOLOGY & PHYSIOLOGY

  • It is important to remember that in anatomy, morphology, and physiology, "Structure correlates to function."

7.1 ANIMAL TISSUES

Key Concepts

  • Animal Organization:

    • All animals are multicellular, with cells joined by cell junctions.

    • Cells are organized into four tissue types:

    • Epithelial tissue

    • Connective tissue

    • Muscle tissue

    • Nervous tissue

    • Organs, consisting of tissue combinations, interact in organ systems.

Organization of Animal Bodies

  • Tissue:

    • Composed of interacting cells and extracellular substances that perform specialized tasks.

  • Organ:

    • Structural unit of two or more tissues organized to carry out specific tasks.

  • Organ systems:

    • Composed of two or more organs interacting in a common task.

Levels of Biological Organization

  • Atom

  • Molecule

  • Cellular Level

    • Example: Epithelial tissue, cells in the small intestine.

  • Tissue Level

  • Organ Level

    • Example: Liver, Stomach, Gallbladder, Large intestine, Small intestine.

  • Organ System Level

  • Organismal Level

FUNCTIONS OF ANIMAL TISSUES

  • Body parts must interact to perform essential tasks:

    • Coordinate and control individual parts.

    • Acquire and distribute raw materials to cells, dispose of wastes.

    • Protect tissues against injury or attack.

    • Reproduce, nourish, and protect offspring during early growth and development.

    • Maintain the internal environment (homeostasis).

CELL JUNCTIONS IN ANIMAL CELLS

  • Types of Cell Junctions:

    • Tight Junctions:

    • Cells are so closely packed they may be impermeable and prevent fluid from seeping between epithelial cells.

    • Adhering Junctions:

    • Use transmembrane linker proteins to hold cells together.

    • Desmosomes:

    • Anchoring junctions that use filaments to anchor to the opposite side.

    • Gap Junctions:

    • Permit ions and small molecules to pass between cells.

SPECIAL CHARACTERISTICS OF EPITHELIA

  • Cell junctions

  • Cilia and Microvilli

  • Apical region of epithelial cells is equipped with characteristics aiding in absorption and secretion.

MAIN TYPES OF ANIMAL TISSUES

  1. Epithelial Tissue

    • Covers the outside of the body and lines organs/cavities.

    • Roles:

    • Protection

    • Absorption

    • Sensory reception

    • Ion transport

    • Secretion

    • Filtration

    • Formation of slippery surfaces for movement

    • Basement membrane is the extracellular matrix that attaches epithelium to underlying tissue.

    • Microvilli are fingerlike projections of absorptive epithelia.

  2. Describing Epithelial Tissues:

    • Thickness:

    1. Simple epithelium: One cell thickness.

    2. Stratified epithelium: More than one cell thickness.

    • Cell Shape:

    1. Squamous: Flattened, wider than tall.

    2. Cuboidal: Cube-shaped, equally tall and wide.

    3. Columnar: Taller than wide.

  3. Types of Epithelial Tissues:

    • (a) Simple Squamous Epithelium:

    • Description: A single layer of flattened cells.

    • Function: Allows passage of materials by diffusion and filtration; secretes lubricating substances.

    • Location: Kidney glomeruli, air sacs of lungs, lining of heart, blood vessels, and lymphatic vessels.

    • (b) Simple Cuboidal Epithelium:

    • Description: A single layer of cubelike cells.

    • Function: Secretion and absorption.

    • Location: Kidney tubules, ducts of glands, ovary surface.

    • (c) Simple Columnar Epithelium:

    • Description: A single layer of tall cells, some with cilia and containing goblet cells.

    • Function: Absorption, secretion of mucus and enzymes.

    • Location: Digestive tract, gallbladder, bronchi.

    • (d) Pseudostratified Columnar Epithelium:

    • Description: A single layer of cells with differing heights, containing goblet cells, possibly ciliated.

    • Function: Secretion of mucus; propels mucus by ciliary action.

    • Location: Trachea, upper respiratory tract.

    • (e) Stratified Squamous Epithelium:

    • Description: Thick membrane of several cell layers; basal cells cuboidal or columnar, surface cells are squamous.

    • Function: Protects underlying tissues from abrasion.

    • Location: Moist linings of the esophagus, mouth, vagina; keratinized variant forms the epidermis of skin.

    • (f) Stratified Cuboidal Epithelium:

    • Description: Generally two layers of cubelike cells.

    • Function: Protection.

    • Location: Ducts of sweat glands, mammary glands, and salivary glands.

    • (g) Stratified Columnar Epithelium:

    • Description: Several layers of cells; basal cells cuboidal surface cells columnar.

    • Function: Protection, secretion.

    • Location: Rare in the body; small amounts in male urethra and large ducts of some glands.

    • (h) Transitional Epithelium:

    • Description: Resembles both stratified squamous and cuboidal; surface cells dome-shaped or squamous-like depending on stretch.

    • Function: Stretches to permit distension by urine.

    • Location: Lines ureters, bladder, part of urethra.

  4. Glandular Epithelium

  • Glands:

    • Organs releasing substances onto skin or into body cavities.

    • Types of Glands:

    1. Exocrine Glands: Have ducts, deliver secretions, e.g., saliva, milk.

    2. Endocrine Glands: Ductless, secrete hormones into blood.

  1. Exocrine Glands:

  • Can be unicellular (e.g., goblet cells) or multicellular.

    • Unicellular produces mucin, which combines with water to form mucus.

    • Multicellular glands have a duct and secretory unit; classified further into tubular and alveolar types.

  1. Types of Exocrine Glands:

    • (a) Simple tubular: E.g., intestinal glands.

    • (b) Simple branched tubular: E.g., gastric glands.

    • (c) Simple alveolar: No important example in humans.

    • (d) Simple branched alveolar: E.g., sebaceous glands.

    • (e) Compound tubular: E.g., duodenal glands of small intestine.

    • (f) Compound alveolar: E.g., mammary glands.

    • (g) Compound tubuloalveolar: E.g., salivary glands.

  2. Endocrine Glands:

  • Ductless glands that release hormones into the extracellular space, which enter the bloodstream to target organs.

  1. Major Endocrine Glands:

    • Pituitary gland, Thyroid gland, Pineal gland, Thymus, Adrenal gland, Pancreas, Testis, Ovary.

B. CONNECTIVE TISSUES

  • Connective tissues are composed of cells and the extracellular matrix they secrete.

  • Functions of Connective Tissues:

    • Connect body parts.

    • Provide structural and functional support to other body tissues.

Types of Connective Tissues

  1. Soft Connective Tissues:

    • More cells than fibers, with thinner, sparsely arranged fibers.

    • Examples:

      1. Areolar

      2. Adipose

      3. Reticular

  2. Dense Connective Tissues:

    • More fibers than cells and ground substance.

    • Types:

      1. Dense regular

      2. Dense irregular

  3. Specialized Connective Tissues:

    • Composed of specialized cells with unique ground substances.

    • Examples:

      • Cartilage

      • Adipose tissue

      • Blood

      • Bone

Soft Connective Tissues:

  • Characterized by dispersed cells and significant extra-cellular material.

  • Loose connective tissue (areolar):

    • Structure: Fibroblasts secrete a matrix of complex carbohydrates with loosely arranged fibers.

    • Function: Wraps/cushions organs, aids in inflammation, holds/conveys tissue fluid.

    • Location: Widely distributed under epithelium; forms lamina propria of mucous membranes.

DENSE CONNECTIVE TISSUES

Dense Irregular Connective Tissue:

  • Description: Primarily irregulary arranged collagen fibers, some elastic fibers; major cell type is fibroblast.

  • Function: Withstands tension in many directions; provides structural strength.

  • Location: Dermis of skin, fibrous capsules of organs/joints.

Dense Regular Connective Tissue:

  • Description: Primarily parallel collagen fibers, a few elastin fibers; major cell type is fibroblast.

  • Function: Attaches muscles to bones; withstands great tensile stress in one direction.

  • Location: Tendons, most ligaments, aponeuroses.

Specialized Connective Tissues

  • Cartilage:

    • Hyaline

    • Description: Amorphous but firm matrix; collagen fibers form a network.

    • Function: Supports and reinforces, resilient cushioning properties.

    • Location: Forms embryonic skeleton, covers ends of long bones.

    • Elastic

    • Description: Similar to hyaline, but with more elastic fibers.

    • Function: Maintains structure while allowing flexibility.

    • Location: External ear, epiglottis.

    • Fibrocartilage

    • Description: Less firm than hyaline; thick collagen fibers predominate.

    • Function: Tensile strength, absorbs compressive shock.

    • Location: Intervertebral discs, pubic symphysis.

  • Blood:

    • Description: Red and white blood cells in a fluid matrix (plasma).

    • Function: Transports gases, nutrients, wastes.

    • Location: Blood vessels.

  • Bone (Osseous Tissue):

    • Description: Hard matrix with many collagen fibers; osteocytes lie in lacunae.

    • Function: Supports, protects, stores calcium and minerals; site for blood cell production.

    • Location: Bones.

C. MUSCLE TISSUES

  • Muscle tissue consists of cells that contract when stimulated and require ATP energy.

  • Three Types of Muscle Tissues:

    1. Skeletal Muscle Tissue:

    • Moves the skeleton (voluntary).

    • Long, striated cells with many nuclei.

    1. Cardiac Muscle Tissue:

    • Heart muscle (involuntary).

    • Striated cells with single nuclei.

    1. Smooth Muscle Tissue:

    • In walls of hollow organs (involuntary).

    • No striations, single nuclei.

Types of Muscle

  • Cardiac muscle

  • Skeletal muscle

  • Smooth muscle

a. Skeletal Muscle

  • Description: Long, cylindrical, multinucleated; obvious striations.

  • Function: Voluntary movement, locomotion, manipulation of environment.

  • Location: In skeletal muscles attached to bones or occasionally skin.

b. Cardiac Muscle

  • Description: Branching, striated, generally uninucleate with intercalated discs.

  • Function: Propels blood into circulation; involuntary control.

  • Location: Walls of the heart.

c. Smooth Muscle

  • Description: Spindle-shaped cells with central nuclei; no striations; closely arranged.

  • Function: Propels substances or objects along internal passageways; involuntary control.

  • Location: Walls of hollow organs.

D. NERVOUS TISSUE

Nervous Tissue

  • Composed of specialized signaling cells (neurons) and supporting cells (neuroglial cells).

  • Functions of Nervous Tissue:

    • Detect internal and external stimuli.

    • Coordinate responses to stimuli.

Neurons

  • Neurons are excitable cells with long cytoplasmic extensions (axons) for transmitting electrochemical signals.

  • Three Types of Neurons:

    1. Sensory Neurons: Excited by stimuli.

    2. Interneurons: Integrate sensory information.

    3. Motor Neurons: Relay commands from the brain/spinal cord to muscles/glands.

Glia/Glial Cells

  • Support neurons by nourishing, insulating, and modulating functions.

Nervous Tissue Description

  • Neurons are branching cells; their processes extend from the cell body. Supporting cells are non-irritable.

  • Function: Transmit electrical signals.

  • Location: Brain, spinal cord, and nerves.

Three Types of Neurons Diagram

  • Enumerating parts: Dendrites, Axon, Cell Body.

Coordination of Cell and Muscle in Nervous Tissue

  • Diagrams illustrating synapses, conduction directions, and comparisons between neurons and muscle fibers.

4 TYPES OF ANIMAL TISSUES

  • Epithelial Tissue: Lines surfaces of the body.

  • Muscle Tissue: Composed of fibers that contract.

  • Nervous Tissue: Composed of cells with projections that transmit electrical signals.

  • Connective Tissues: Provide support and connect body parts; includes bone, cartilage, blood.

QUIZIZZ

  • Steps to access the quiz:

    1. Use any device to visit joinmyquiz.com.

    2. Enter join code 540232.

BRAINSTORMING QUESTIONS

  1. Identified types of epithelial tissue based on thickness and shapes.

  2. Name the parts of a neuron and their functions.

THANK YOU

  • Closing remarks.