Chapter 4 Reading Guide
Overview
This reading guide is intended to be used with the Open Stax Anatomy and Physiology textbook.
Open Stax Anatomy and Physiology Chapter 4 Reading Guide
Human Anatomy and Physiology
Chapter 4: The Tissue Level of Organization
4.1 Types of Tissues
The Four Types of Tissues
- _____________ – (epithelium), are sheets of cells that cover the exterior surfaces of the body, line internal cavities and passageways, and form glands.
- _____________ – binds the cells and organs of the body together
- Functions in the protection, support, and integration of all body parts.
- _____________ – excitable cells respond to stimulation and contraction to provide movement
- Three major types: skeletal (voluntary), smooth, and cardiac.
- ____________________ – excitable cells that transmit electrochemical impulses throughout the body.
- Embryonic Origin of Tissues
- _____________ – A single cell formed by the fusion of sperm and egg.
- Undergoes repeated mitotic cell divisions (cleavage) to form an embryo.
- These first embryonic cells are _____________, meaning that each one of these cells has the capacity to form a new organism
- As cell division and cellular specialization continues three distinct germ layers form in the embryo.
- _____________ – outer layer
- _____________ – middle layer
- _____________– inner layer
Tissue Membranes
- ____________________– a thin layer of sheet of cells that covers the outside of the body, the organs, and internal passageways that lead to the exterior of the body, and the lining of the movable joint cavities
- Two types of tissue membranes
- Connective tissue
- Epithelial membranes
- Figure 4.4 Tissue Membranes
- Connective Tissue Membranes
- ____________________________ is formed from connective tissue
- ____________________– lines the cavity of a freely movable joint
- E.g. shoulder, elbow, and knee
- Synovial fluid is produced by the synovial membrane which exchanges water and nutrients with blood.
Epithelial membranes
- ____________________ is formed of epithelium attached to a layer of connective tissue (your skin).
- ____________________– a composite of connective and epithelial tissues
- Line the body cavities
- Hollow passageways (blood vessels)
- Digestive, respiratory, excretory, and reproductive tracts
- ____________________ – connective tissue that underlies the fragile epithelial layer.
- ____________________ – an epithelial membrane derived from mesothelium, line all body cavities that do not open to the exterior.
- Secrete serous fluid which reduces internal friction
- _____________ membranes cover the lungs
- _____________ covers the heart
- _____________ – covers the abdominal organs and forms mesenteries
- ____________________ – the skin
- Stratified squamous epithelium resting on top of connective tissue
- 4.2: Epithelial Tissue
- Characteristics of Epithelial Tissue
- Large sheets of cells covering all body surfaces inside and outside.
- Forms most of the glandular tissue of the body.
- Derived from all three germ layers
- Important structural and functional features
- No extracellular material
- Epithelial cells form specialized intercellular connections called ____________________.
- Cells exhibit polarity between the exposed (_____________) surface and the _____________ surface (attached to underlying tissues).
- ____________________ secreted by epithelial cells attaches the basal surface to underlying connective tissue.
- _____________ is secreted by underlying connective tissue attaches to the basal lamina to form a ____________________ that holds it all together.
- Avascular does not have its own blood supply.
- Continuously dividing to replace damaged and dead cells.
Cell to Cell Junctions
- Three basic types that allow interaction between cells.
- ____________________– separates cells into apical and basal compartments.
- Two adjacent epithelia cells linked by tight junctions have no extra cellular space between them, thus blocking the movement of substances between cells.
- ____________________ – stabilize epithelial tissues, common on the lateral and basal surfaces, and provide strong, flexible connections.
- ____________________ – occur in patches and link cells together.
- ____________________– link cells to the basal lamina.
- _____________– influence the shape and folding of epithelial tissue.
- ____________________ – forms an intercellular passageway between adjacent cells. Allow the movement of small molecules and ions between cells.
- Classification of Epithelial Tissues
- Figure 4.6 Cells of Epithelial Tissue
- Simple Epithelium
- ______________________________Cells appear as flat scales
- Absorption of chemical compounds, diffusion of gases
- Line blood vessels (_____________), alveoli of lungs, segments of kidney tubules
- Forms ____________________ that forms the surface layer of serous membranes.
- Stratified Epithelium
- Consists of stacked layers of cells that protect against wear and tear.
- ____________________
- Most common type of stratified epithelium in the body.
- Apical cells are squamous with the basal layer consisting of columnar or cuboidal cells.
- The top layer may be covered with dead, keratinized cells (as in human skin).
- The lining of the mouth is an example of unkeratinized stratified squamous epithelium.
- Stratified cuboidal and stratified columnar epithelium is found in certain glands or ducts but is mostly uncommon in the human body.
- ____________________ is found only in the urinary system, the shape of the cells changes as it is stretched.
Glandular Epithelium
- Glands are structures that synthesize and secrete chemical substances
- Classification of glands
- ____________________ – ductless glands that release secretions directly into surrounding tissues and fluids.
- Secrete hormones into the interstitial fluid, the blood stream and delivered to targets.
- Pituitary gland, thymus, adrenal cortex, pancreas, and gonads
- ____________________– secretions leave through a duct opening directly or indirectly into the external environment.
- Mucous, sweat, saliva, and breast milk.
- Structure of exocrine glands
- Unicellular – goblet cells that are found in mucous membranes
- Multicellular
- Serous glands secrete directly into the body cavity
- Simple glands release secretions through s single tubular duct
- Compound glands – the duct is divided not one or more branches
Methods and Types of Secretion
- ____________________ – secretion by vesicles where the contents are released by exocytosis
- Goblet cells, sweat glands
- ____________________Secretions accumulate at the apical end of the cell, which pinches off and is released.
- Apocrine sweat glands in the axillary and genital areas
- ____________________
- Involves the rupture and destruction of the gland cell.
- New gland cells replace the lost cells.
- Sebaceous glands of the skin and scalp.
- ____________________
- Produce watery, blood plasma like secretions rich in enzymes.
- ____________________
- Releases products rich in mucin.
4.3 Connective Tissue: Shapes and Protects
- Characteristics of Connective Tissue
- Composed of cells dispersed throughout an extracellular _____________.
- A mixture of secretions produced by the connective tissue cells embedded in it.
- The major component is an amorphous ____________________with protein fibers. This substance may be liquid or mineralized.
- Functions of Connective Tissues
- Support and connect other tissues
- Protection
- Defend the body from microorganisms
- Transport of fluids, waste, and hormones
- Store surplus energy as fat and contribute to thermal insulation of the body.
Embryonic Connective Tissue
- All connective tissue derives from the mesoderm layer of the embryo.
- _____________ - the first connective tissue found in the embryo, is the stem cell line from which all connective tissues develop from.
- _____________ connective tissue (Wharton’s jelly) – only forms in umbilical cord, not present after birth.
- Classification of Connective Tissue
- _____________ Tissue Proper – consist of a variety of cell types and protein fibers embedded in ground substance
- _____________ connective tissue – Fibers are loosely organized leaving large spaces between
- _____________ connective tissue – Reinforced by bundles of fibers closely packed together that provide strength, elasticity, and protection
- _____________ connective tissue – includes bone and cartilage
- Few distinct cell types with tightly packed fibers
- _____________ connective tissue – lymph and blood
- Specialized cells circulate in a watery fluid containing dissolved salts, nutrients, gases, and dissolved proteins.
- Connective Tissue Proper
- Cell Types
- _____________ are the dominant cell type, form the extracellular matrix.
- _____________ – less active and the second most common cell type.
- _____________ store lipids
- _____________ – multipotent adult stem cell can differentiate into any type of connective tissue cell needed.
- _____________ – type of leukocyte, essential component of immune system
- _____________– involved in inflammatory responses, release histamine.
- Connective Tissue Fibers and Ground Substance
- _____________ fibers – made of fibrous protein subunits, form long and straight fibers
- Flexible with great tensile strength, resist stretching give tendons and ligaments their resilience and strength.
- _____________ fibers contain the protein elastin, may be stretched, and return to its original shape
- Found in skin and elastic ligaments of the vertebral column.
- _____________ fiber – formed from the same protein subunits as collagen fibers.
- Fibers are narrow and arranged in a branched network.
- Most abundant in the liver and spleen.
- Anchor and provide structural support to the functional cells, blood vessels and nerves of those organs (parenchyma)
- Ground substance
- Secreted by fibroblasts, made of polysaccharides, specifically hyaluronic acid, and proteins
- Loose Connective Tissue
- Found between organs, acts as a shock absorber, and binds tissues together.
- ____________________– make of fat storage cells (adipocytes) with little extracellular matrix.
- _____________contributes to lipid storage and insulation
- _____________ – thermogenic as it breaks down heat is released
- _____________ tissue underlies most epithelia and represents the connective tissue component of epithelial membranes
- _____________ tissue forms a mesh-like supportive framework for soft organs, spleen, and liver.
Dense Connective Tissue
- Contains more collagen fibers than loose connective tissue, has greater resistance to stretching.
- Two major categories of dense connective tissue
- R_____________ – Contain elastic fibers along with collagen fibers that are parallel to each other, enhancing tensile strength and resistance to stretching.
- Ligaments and tendons, and vocal fold ligaments.
- Ir_____________ – Fibers proceed in random directions, tissue may form a mesh,
- Dermis of skin, arterial vessel walls
Supportive Connective Tissues
- Allow the body to maintain its posture and protect internal organs.
- Cartilage
- Ground substance contains chondroitin sulfates
- _____________ – cartilage cells embedded in ground substance
- _____________ – (lacuna) space occupied by chondrocytes.
- Enveloped by the perichondrium, a layer of dense irregular connective tissue
- Avascular
- Three main types of cartilage
- H_____________ – most abundant found in rib cage, nose, and lines joints, forms the embryonic skeleton.
- F____________________ – tough with thick bundles of collagen fibers, form menisci of the knee and vertebral discs.
- E_____________ – contain elastic fibers, your earlobe.
- Figure 4.16 Types of Cartilage
- Bone is the hardest connective tissue. It provides protection and support.
- An extracellular matrix of collagen fibers embedded in mineralized ground substance called hydroxyapatite, a form of calcium phosphate.
- Osteocytes – bone cells located inside lacunae
- Highly vascularized
- Types of bone tissue
- Ca_____________ – has a spongy appearance, lighter than compact bone
- Found in the interior of bones and at the end of long bones.
- Co_____________ – is solid and has greater structural strength
Fluid Connective Tissue
- Specialized cells circulate in a liquid extracellular matrix.
- All blood cells are derived from hematopoietic stem cells found in red bone marrow.
- E_____________ – red blood cells contain hemoglobin and transport oxygen and carbon dioxide.
- L_____________ – white blood cells defend against microorganisms or harmful molecules
- Pl_____________ – cell fragments involved in blood clotting.
- L_____________ – consists of a liquid matrix and white blood cells
- L_____________ capillaries capture excess interstitial fluid and transport it back to the blood vessels
- Specialized lymphatic capillaries (l_____________) transport absorbed fat away from the intestine and deliver it to the blood.
4.4 Muscle Tissue and Motion
- Characteristics of Muscle Tissue
- Responds to stimuli
- Allows movement
- Made up of contractile cells
- Movement may be voluntary or involuntary
- Classifications of Muscle Tissue
- 3 types according to structure and function
- Sk_____________
- C_____________
- Sm_____________
- Comparison of Structure and Properties of Muscle Tissue Types
- Sk_____________ muscle:
- Attached to bones, contraction make movement possible
- Shivering generates heat
- Derived from mesoderm, myoblasts give rise to myocytes (muscle fibers).
- Fibers are arranged in bundles surrounded by connective tissues
- Microscopic appearance shows striations with many nuclei
- Striations are composed of the contractile protein's a______ and m________
- Skeletal muscle fibers are many myocytes joined end to end to form a long muscle fiber.
- _____________ muscle
- Forms the contractile walls of the heart
- Cardiomyocytes are single cells with a centrally located nucleus.
- Each cell contracts on its own without external stimulation
- Cardiomyocytes attach to others with intercalated discs (specialized cell junctions).
- Under involuntary control
- _____________ muscle
- Involuntary movements in the internal organs
- Contractile component of the digestive, urinary, and reproductive tracts.
- Airways and arteries
- Spindle shaped cells, single nucleus, no visible striations
4.5: Nervous Tissue Mediates Perception and Response
- Characteristics of Nervous tissue
- Excitable, sends and receives electrochemical signals to provide the body with information.
- Nervous tissue is composed of
- N_____________
- Generate nerve impulses (action potentials)
- Display distinct morphology
- Three main parts
- _____ body includes most of the cytoplasm, organelles, and nucleus
- D__________ are numerous branches off the cell body
- A_____– a single long process, extending from the cell body, wrapped in an insulating material called _______.
- N_________ - Support and nourish neurons
- Have very complex roles in the functioning of the brain and nervous system
- A_____________ – distinct star shape abundant in CNS, regulate ion concentrations, uptake and breakdown of neurotransmitters, formation of blood – brain barrier.
- O____________________ – produce myelin in the CNS.
- S_____________ cells – produce myelin in the peripheral nervous system
4.6: Tissue Injury and Aging
- Tissue Injury and Repair
- Inflammation – the body’s initial response to any injury
- Limits the extent of injury, helps eliminate the cause of injury, initiates repair and regeneration of damaged tissue.
- N_____________ – accidental cell death is one cause of inflammation
- Ap_____________ – programmed cell death, destroys cells not needed by the body does not cause inflammation.
- _____________ inflammation is resolved over time by the healing of tissue
- _____________ inflammation is when inflammation persists over time and leads to diseased conditions such as:
- Arthritis
- Tuberculosis
- Four cardinal signs of inflammation have been known since antiquity
- Redness, swelling, pain and local heat along with loss of function.
- Upon tissue injury
- Damaged cells release chemical signals
- Mast cells release h_____________ a vasodilator
- V_____________ – widening of the blood vessels in the injured area which increases blood flow leading to redness and heat
- This attracts white blood cells to the damaged area
- Local blood vessels endothelium becomes leaky allowing white blood cells and fluid to move into the interstitial space causing e_____ a localized swelling.
- Stretched pain receptors cause pain.
- Cl_________ occurs (coagulation) reducing blood loss forming a fibrin patch to bind the edges of the wound together resulting in scab formation.
- Fibroblasts replace collagen and lost extracellular material.
- A_____________ the growth of new blood vessels occurs
- New tissue forms (granulation tissue)
- P___________ union – describes the healing of a wound when the edges are close together.
- S_____________ union – describes a gaping wound in which the edges are pulled together by _____________ contraction, which results in scar formation.
- Sutures are recommended for wounds more than ¼ inch deep to promote primary union and avoid scar formation.