Midterm 1- Anatomy and Physiology Notes PDF

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Stephen Gee and Micheal Downey ...

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Human Anatomy and Physiology Notes Lecture 1- Introduction, Structure, Function and Cell Theory Overview ● When referring to anatomy/Physiology of the body, we assume that we are talking about a healthy 22-year old male weighing 155 lbs or a health young female weighing 125 lbs Topics of Anatomy ● Is the study of the structure of body parts ● Must memorize ● Major subdivisions of anatomy are: ○ Gross anatomy- the study of large body structures ■ Regional anatomy- study of structures in particular region ■ Systematic anatomy- body structure is studied system by system ■ Surface anatomy- study of internal structures as they relate to the overlying skin surface ○ Microscopic anatomy- study of structures that can’t be seen with naked eye ■ Cytology- considers cells of body ■ Histology- the study of tissues ○ Developmental anatomy- traces structural changes that occur in body throughout lifespan ■ Embryology- study of developmental changes that occur before birth Topics of Physiology ● Physiology is the study of the functions  of the body ● Must understand ● Subdivisions concern the individual specific organ systems ○ Eg; neurophysiology, cardiovascular physiology, etc. ● Often focuses on events at a cellular/molecular level Complementarity of Structure and Function ● Anatomy and physiology is inseparable as function always reflects structure ● This key concept is called the principle of complementarity of structure and function ● You can infer function from structure Scientific Reductionism ● Reductionism- an approach to understanding the nature of complex things by reducing them to simpler things ● Physiology often focuses on events at the cellular or molecular level because the body’s abilities depend on individual cells

Levels of Structural Organization ● Body’s organization ranges from atoms (smallest unit) to the entire organism (largest unit) ● Levels of structural organization (simplest to most complex): chemical, cellular, tissue, organ, organ system and organismal ○ Chemical level- atoms combine to form molecules ○ Cellular level- Cells are made up of molecules ○ Tissue level- Groups of similar cells with a common function ■ 4 types- epithelial, muscle, connective, and nervous ○ Organ level- Structure composed of two (usually 4) tissue types. Specialized functional structure for specific activity ○ Organ System level- organs work together to accomplish a common purpose ○ Organismal level- An organism is made up of numerous organ systems Organ Systems of the Body Organ System

Function

Integumentary System

● Forms external body covering + protects deep tissues from injury ● Synthesizes vitamin D and houses external stimuli receptors and sweat and oil glands ● Hair, nails, skin

Skeletal System

● Protects + supports organs ● Provides framework that muscles use for movement ● Blood cells synthesized in bones and bones store minerals

Muscular System

● Allows manipulation of the environment, locomotion and facial expression ● Maintains posture + produces heat

Nervous System

● Fast- acting control system of body ● Responds to external and internal stimuli by activating appropriate muscles and glands

Endocrine System

● Glands secrete hormones which regulate numerous body processes

Cardiovascular System

● Blood vessels transport blood and other nutrients to the body ● Heart pumps the blood

Lymphatic System

● Picks up fluid leaked from blood vessels and returns it to blood ● Disposes of debris in the lymphatic stream ● Houses white blood cells (lymphocytes) involved in immunity

Respiratory

● Keeps blood supplied with oxygen + removed carbon dioxide

System

● Gas exchange occurs through walls of air sacs in lungs

Digestive System

● Breaks down food to be absorbed by blood ● Indigestible foods eliminated as feces

Urinary System

● Eliminates nitrogenous wastes from body ● Regulates water, electrolyte and acid-base balance of the blood

Reproductive System

● Male and female ● Used for production of offspring

Parts of a Cell: Structure and Function ● Refer to the following lecture 1 powerpoint for condensed chart ● https://uottawa.brightspace.com/d2l/le/content/117592/viewContent/2387015/View Organelles In The Cytoplasm ● Is the region between nuclear and plasma membranes ● Consists of cytosol, organelles and inclusions (stored nutrients, secretory products, pigment granules) Organelle

Structure

Function

● Rodlike, double-membrane structure ● Outer membrane is smooth ● Inner membrane folded into projections called cristae ● Gel-like matrix in the center

● Site of ATP synthesis ● Powerhouse of the cell ● Has own DNA and replicates independently

Ribosomes

● Consist of 2 subunits, each composed of ribosomal RNA and protein ● Free or attached to rough ER

● Synthesize proteins for various cell needs ● Can switch back and forth between free floating and bounded states

Rough ER

● Outer surface is covered in ribosomes ● Membranous ● Coils through the cytoplasm

● External face synthesizes proteins ● Integral proteins and phospholipids are also manufactured ● Proteins are bound in vesicles and transported to the Golgi apparatus and other sites

Smooth ER

● Is continuous with rough ER ● Membranous system of sacs and tubules ● No ribosomes

● Does not make proteins ● Contains enzymes that are responsible for synthesizing lipids and steroids, lipid metabolism and drug

Mitochondria

detoxification Golgi Apparatus

● Stack of flattened membranes and vesicles ● Located near the nucleus

● Packages, modifies and segregates proteins and lipids made in the rough ER for secretion from the cell, inclusion in lysosome and incorporation in plasma membrane

Peroxisomes

● Membranous sacs of catalase and oxidase enzymes

● Oxidase enzyme detoxifies many toxic substances and neutralizes free radicals ● Catalase (important enzyme) breaks down hydrogen peroxide

Lysosomes

● Membranous sacs containing acid hydrolases ● Spherical

● Sites of intracellular digestion ● Work best in acidic conditions

Microtubules

● Cylindrical ● Composed of tubulin proteins

● Support cell and gives it shape ● Involved in intracellular and cellular movements ● Form centrioles, cilia and flagella

Microfilament s

● Fine filaments composed of protein actin

● Involved in muscle contraction and other intracellular movements ● Helps form cell’s cytoskeleton

● Protein fibers ● Composition varies

● Make up the stable cytoskeleton ● Resist mechanical forces acting on cell

Centrioles

● Paired cylindrical bodies ● Each composed of nine triplets of microtubules

● Organize microtubule network during mitosis to form the spindle and asters ● Form the bases of cilia and flagella

Inclusions

● Varied

● Are storage for nutrients, wastes and cell products

Intermediate Filaments

Cellular Extensions Part

Structure

Function

Cilia

● Short, cell surface projections ● Composed of nine pairs of microtubules surrounding a central pair

● Their coordinated movement creates a current that propels substances across cell surfaces

Flagellum

● Like cilium, but longer ● Only present in sperm cells in humans

● Propels the cell in its environment

● Tubular extensions of plasma membrane ● Contain bundle of actin fibers

Microvilli

● Increase surface area for absorption

Parts Of The Nucleus Part

Structure

Nucleus

● Largest organelle ● Surrounded by nuclear envelope ● Contains fluid nucleoplasm, nucleoli and chromatin

● Control center of cell ● Transmits genetic information ● Provides instructions for protein synthesis

Nuclear Envelope

● Double membrane ● Porous ● Outer membrane is continuous with ER

● Separates nucleoplasm from cytoplasm ● Regulates passage of substances to and from the nucleus

Nucleolus

● Dense, spherical bodies ● Non-membrane bound ● Composed of RNA and proteins

● Site of ribosome subunit synthesis

● Granular and threadlike ● Composed of 30% DNA, 60% histone proteins and 10% RNA chains

● Fundamental units are nucleosomes ● Packs DNA into a small volume to fit the nucleus ● Protects DNA structure and sequence

Chromatin

Function

Maintaining life ● Necessary Life Functions ○ All organisms carry out specific vital functional activities necessary for life ○ Include maintenance of boundaries, movement, digestion, responsiveness, metabolism, excretion, reproduction and growth ● Survival Needs -Requirements for maintaining life ○ Nutrients- taken through diet. Contain chemical substances required for energy and cell building ○ Oxygen- chemical reactions that release energy from foods are oxidative reactions that require oxygen ○ Water- accounts for 60-80% of body weight. Provides necessary environment for chemical reactions ○ Body Temperature- Normal body temperature is required for chemical reactions to occur. Muscular system activity generates the most heat. ○ Atmospheric Pressure- breathing and gas exchange are dependent on appropriate atmospheric pressure.

Lecture 2- Types of Tissues Processes Needed to Make Us Multicellular ● Cell division ● Work with environment ● Movement ● Cell differentiation ● Cell-Cell interactions ○ Direct interactions, endocrine and nervous system signal interactions Tissues ● Are groups of cells that are similar in structure and perform a common function ● Are four basic types of tissues in the body ○ Epithelial, connective, nervous and muscle tissue ● In short, epithelial tissue covers, connective tissue supports, nervous tissue controls and muscle tissue provides movement Overview of 4 Basic Tissues Tissue

Function

Location

Nervous Tissue

Internal communication

Brain, spinal cord, nerves

Muscle Tissue

Contracts to cause movement

Skeletal muscles Cardiac muscles Muscles of the walls of hollow organs (smooth muscles)

Epithelial Tissue

Forms boundaries, protects, secrets, absorbs, filters

Lining of digestive track and hollow organs Glands Skin Surface

Connective Tissue

Supports, protects, binds other tissues together

Bones, tendons, fat and other soft padding tissue

Preparing Human Tissues for Microscopy ● Histology- the study of tissues ● Microscopy allows for the study of tissue structure ● Before viewing, the specimen must undergo the following steps in order; ○ It must be fixed (preserved) ○ Then, it must be cut into sections (slices) thin enough to transmit light/electrons ○ Finally, it must be stained to enhance contrast (light microscopy) ● Transmission electron microscopy (TEM)

○ Tissue sections are stained with heavy metal salts that deflect electrons in the beam to different extents, providing contrast ● Scanning electron microscopy (SEM) ○ Provided 3-D pictures of an unsectioned tissue surface Type 1- Epithelial Tissue ● Is a sheet of cells that covers a body surface or lines a body cavity ● Two forms occur in the body ○ Covering and lining epithelium ■ Forms outer layer of the skin ■ Lines the open cavities of the urogenital, digestive and respiratory systems ■ Covers the walls and organs of the closed ventral body cavity ○ Glandular epithelium ■ Covers the glands of the body ■ Secretory tissue in glands (eg; salivary glands) ● All substances received or given off by the body have to pass through the epithelium ○ Selective barrier- intestinal epithelium allows passage of certain substances ■ Bidirectional, highly regulated in healthy and not healthy tissue ■ Gut microbiome ● Accomplishes many functions including; ○ Protection, absorption, secretion, filtration, excretion, sensory reception Special Characteristics of Epithelium ● Has five distinguishing characteristics ○ Polarity, specialized contacts, supported by connective tissue, avascular but innervated, ability to regenerate ● Polarity ○ Apical surface (top) is exposed to surface or cavity ■ Most are smooth, but some have microvilli (increases surface area) or cilia ○ Basal surface (bottom), faces inwards towards body ■ Attached to basal lamina, an adhesive sheet that holds the basal surface of epithelial cells to underlying cells ● Acts as a selective filter that determines which molecules diffusing from underlying tissue are allowed in ○ Cell polarity is crucial for normal cell physiology and tissue homeostasis ● Specialized Intercellular Contacts ○ Cells need to fit closely together to form barrier ○ Specialized contact points bind adjacent epithelial cells together (between cells) ○ Lateral contacts include; ■ Tight junctions- prevents substances from leaking between cells (regulated) ■ Adherens junctions- mediate cell-cell adhesion via protein cadherins

■ Desmosomes- prevents cells from pulling apart in tissues subjected to mechanical stress (made up of protein desmoglein) ■ Gap junctions- mediated by connexions. Intercellular communication. ○ Use different connecting proteins and attach to different filaments ● Supported by Connective Tissue ○ All epithelia have a basement membrane (BM) ■ reinforces , resists stretching, tearing ■ Defines epithelial boundary ■ Consists of ● Basal lamina- layer of extracellular matrix (ECM) proteins ● Reticular lamina- deep to the basal lamina. Network of collagen III fibers ○ Disease Relevance- cancerous epithelial cells can penetrate BM and invade underlying tissues, resulting in spread of cancer (metastasis)---> 90% of cancer deaths ● Avascular, But Innervated ○ Avascular- no blood vessels ■ Nutrients and oxygen diffuse from connective tissue ○ Innerved- have nerves ● Regeneration ○ Epithelials cells have high regenerative capacities ○ Simulated by loss of apical-basal polarity and broken lateral contacts ○ Some cells exposed to friction, hostile substances ----> damage ■ Must be replaced ■ Requires adequate nutrients and cell division ■ Wound healing Classification of Epithelia ● Based on two factors ● Number of cell layers (1 or more) ○ Simple epithelia- a single layer thick ○ Stratified epithelia- are two or more layers thick ■ Protection is a major role ■ New cells regenerate from below ● Basal cells divide and migrate to surface ■ More durable than simple epithelia ● Shape of cells ○ Squamous: flattened and scale-like (humans have a lot of them) ■ Most of the cells in the outer layer of skin ■ Passages of respiratory and digestive tracts ■ Lining of hollow organs ○ Cuboidal: box-like, cube

○ Columnar: tall, column-like ■ In stratified epithelia, shape can vary in each layer, so classified according to shape in apical layer Types of Simple Epithelium Type and Image

Description

Function

Location

Simple Squamous

-Single layer of flattened cells. -Disk shaped nuclei -Sparse cytoplasm -Simplest of epithelia -Two types based on location *(see bottom for note)*

-Allows materials to pass via diffusion and filtration in sites where protection is not key, but rapid diffusion is. -Secretes lubricating substances in serosae (lining of ventral body cavity)

-Kidney glomeruli -Air sacs of lungs -Lining of heart -blood vessels -lymphatic vessels -Serosae

Simple Cuboidal

-Single layer of cube like cells -spherical central nuclei

-Secretion and absorption

-Kidney tubules --Ducts and secretory portions of small glands -Ovary surface

Simple Columnar

-Single layer of tall cells with round to oval nuclei -Many have microvilli -Some have cilia -Layer may contain mucus-secreting unicellular glands (goblet cells)

-Absorption -Secretion of mucous, enzymes and other substances -Ciliated type propelles mucous (or reproductive cells)

-Non-ciliated line most of digestive tract (stomach to rectum), gallbladder, and excretory ducts of some glands -Ciliated type lines small bronchi, uterine tubes, and some parts of uterus

Simple Pseudostratified Columnar

-Single layer of cells differing in height -Nuclei seen at different levels -May contain mucus-secreting cells and have cilia

-Secrete substances, mainly mucous -Propulsion of mucus by ciliary action

-Ciliated type lines trachea and most of upper respiratory tract -Nonciliated type in male sperm-carrying ducts and ducts of large glands

*There are two types of simple squamous epithelium based on location; ● Endothelium

○ Lines inner surface of blood vessels, lymphatic vessels, and the heart ○ Derived from ectoderm and endoderm in the early embryo ● Mesothelium ○ Form serous membranes- surround pericardium, peritoneum, pleura, and internal reproductive organs (covers outer surface) ○ Derived from mesoderm ○ Two membrane system with fluid in between Types of Stratified Epithelium Type/Image

Description

Function

Location

Stratified Squamous

-Thick, composed of several layers -Most widespread -Basal cells are cuboidal or columnar and metabolically active -surface cells are flattened (squamous) -Keratinized type- surface cells are dead and full of keratin. Basal cells are active in mitosis and produce superficial layer cells

-Protects underlying tissue in areas subject to abrasion

-Located in areas of high wear and tear -Keratinized cells found in skin and nonkeratinized found in moist linings of mouth, esophagus and vagina

Stratified Cuboidal

-Very rare -Typically only two layers thick

-Found in some sweat and mammary glands

Stratified Columnar

-Very rare in the body -only apical layer is columnar

-Transitional areas between two other types of epithelia -Small amounts found in pharynx, male urethra, and lining of some glandular ducts

Transitional

-Resembles both stratified squamous and stratified cuboidal -Basal cells are cuboidal or columnar -Surface cells dome-shaped or squamous like depending on the degree of organ stretch

Glandular Epithelia

-Stretches readily -Permits stored urine to distend urinary organ

-Lines the ureters, bladder and part of the urethra

● Gland-one or more cells that make and secrete an aqueous fluid called a secretion  ● Classified by two factors ○ Site of product release ■ Endocrine- internally secreting ■ Exocrine- externally secreting ○ The relative number of cells forming the gland ■ Unicellular (eg. goblet cells) or multicellular (eg. salivary) Formation of Multicellular Exocrine & Endocrine Glands ● Multicellular epithelial glands form by invagination (inward growth) of an epithelial sheet ● Exocrine glands retain the connecting cells, which form a duct that transports secretions to the epithelial surface ● Endocrine glands lose their ducts during development ○ Secrete hormones into the interstitial fluid which ten enter the blood Formation of Multicellular Endocrine & Exocrine Glands ● Multicellular epithelial glands form by invignation (inward growth) of an epithelial sheet ○ Exocrine glands retain connecting cells which form a duct that transports secretions into the epithelial surface ○ Endocrine glands lose their ducts during d...