Chapter 1 The Human Body: An Orientation

1. Chapter 1The Human Body: An Orientation Anatomy and Physiology

2. Bellwork • On a sheet of paper, put todays date. Keep this sheet until Friday because you will put each days bellwork on this sheet. Answer the question/statement below. • Define Anatomy and Physiology. • How are structure and function related? Tell me what you already know…

3. The Student Should Be Able To: • Differentiate between Anatomy and Physiology • List necessary life functions (8) • List survival needs (5) • Explain homeostasis and give examples of types of feedback

4. Overview of Anatomy and Physiology • Anatomy • Study of structure and shape of the body parts and their relationships to one another. • “ana”- apart and “tomy” to cut • Subdivisions: • Gross or macroscopic (e.g., regional, systemic, and surface anatomy) • Microscopic (e.g., cytology and histology) • Developmental (e.g., embryology)

5. Overview of Anatomy and Physiology • Physiology • Study of the function of the body • “physio” nature, “ology” study of • Subdivisions based on organ systems(e.g., renal or cardiovascular physiology) • Often focuses on cellular and molecular level • Body's abilities depend on chemical reactions in individual cells

6. Principle of Complementarity • Anatomy and physiology are inseparable • Function always reflects structure • What a structure can do depends on its specific form

7. Necessary Life Functions • Maintaining boundaries • Movement • Responsiveness • Digestion • Metabolism • Dispose of wastes • Reproduction • Growth

8. Necessary Life Functions • Maintaining boundaries between internal and external environments • Skin • Movement • Includes activities promoted by the muscular system • Aided by the skeletal system

9. Necessary Life Functions • Responsiveness • Irritability • Ability to sense changes and respond to stimuli • Nervous system responsible for this function • Digestion • Breakdown of ingested foodstuffs • Absorption of simple molecules into blood

10. Necessary Life Functions • Metabolism • All chemical reactions that occur in body cells • Regulated by hormones (where do hormones come from?) • Excretion • Removal of wastes from the body • Urea, carbon dioxide, feces (which systems?)

11. Necessary Life Functions • Reproduction • Cellular division for growth or repair • Production of offspring • Regulated by hormones • Growth • Increase in size of a body part or of organism

12. Interdependence of Body Cells • Humans are multicellular • To function, must keep individual cells alive • All cells depend on organ systems to meet their survival needs • All body functions spread among different organ systems • Organ systems cooperate to maintain life • Note major organs and functions of the 11 organ systems (fig. 1.3)

13. Survival Needs • Appropriate amounts necessary for life • Too little or too much harmful • Nutrients • Oxygen • Water • Normal body temperature • Appropriate atmospheric pressure

14. Survival Needs • Nutrients • Chemicals for energy and cell building • Carbohydrates, fats, proteins, minerals, vitamins • Oxygen • Nutrients are useless without oxygen • Chemical reactions require oxygen • 20% of air we breathe

15. Survival Needs • Water • Most abundant chemical in body • Fluid base for secretions and excretions • 60-80% of body weight • Normal body temperature • 37 C or 98  F • Affects rate of chemical reactions • Appropriate atmospheric pressure • Force exerted on body surface by weight of air • For adequate breathing and gas exchange in lungs

16. Homeostasis • Homeostasis • Maintenance of relatively stable internal conditions despite continuous changes in environment • A dynamic state of equilibrium • Maintained by contributions of all organ systems

17. Homeostatic Control Mechanisms • Involve continuous monitoring and regulation of all factors that can change (variables) • Communication necessary for monitoring and regulation • Functions of nervous and endocrine systems • Nervous and endocrine systems accomplish communication via nerve impulses and hormones

18. Components of a Control Mechanism • Receptor (sensor) • Monitors environment • Responds to stimuli (something that causes changes in controlled variables) • Control center • Determines set point at which variable is maintained • Receives input from receptor • Determines appropriate response • Effector • Receives output from control center • Provides the means to respond • Response either reduces (negative feedback) or enhances stimulus (positive feedback)

19. Figure 1.4 Interactions among the elements of a homeostatic control system maintain stable internalconditions. Slide 1 4 3 Input:Information sent along afferent pathway to control center. Output:Information sent along efferent pathway to effector. Control Center Afferent pathway Efferent pathway Receptor Effector 2 Receptor detects change. 5 Response of effector feeds back to reduce the effect of stimulus and returns variable to homeostatic level. IMBALANCE 1 Stimulus produces change in variable. BALANCE IMBALANCE

20. Negative Feedback • Most feedback mechanisms in body • Response reduces or shuts off original stimulus • Variable changes in opposite direction of initial change • Examples • Regulation of body temperature (a nervous system mechanism) • Regulation of blood glucose by insulin (an endocrine system mechanism)

21. Figure 1.5 Body temperature is regulated by a negative feedback mechanism. Control Center (thermoregulatory center in brain) Efferent pathway Afferent pathway Receptors Temperature-sensitive cells in skin and brain) Effectors Sweat glands Sweat glands activated Response Evaporation of sweat Body temperature falls; stimulus ends IMBALANCE Body temperature rises BALANCE Stimulus: Heat Stimulus: Cold Response Bodytemperaturerises; stimulusends Body temperature falls IMBALANCE Receptors Temperature-sensitive cells in skin and brain Effectors Skeletal muscles Afferent pathway Efferent pathway Shivering begins Control Center (thermoregulatory center in brain)

22. Negative Feedback: Regulation of Blood Volume by ADH • Receptors sense decreased blood volume • Control center in hypothalamus stimulates pituitary gland to release antidiuretic hormone (ADH) • ADH causes kidneys (effectors) to return more water to the blood

23. Positive Feedback • Response enhances or exaggerates original stimulus • May exhibit a cascade or amplifying effect • Usually controls infrequent events that do not require continuous adjustment • Enhancement of labor contractions by oxytocin (chapter 28) • Platelet plug formation and blood clotting

24. Figure 1.6 A positive feedback mechanism regulates formation of a platelet plug. Slide 1 1 Break or tear occurs in blood vessel wall. Positive feedback cycle is initiated. 3 2 Released chemicals attract more platelets. Platelets adhere to site and release chemicals. Positive feedback loop Feedback cycle ends when plug is formed. 4 Platelet plug is fully formed.

25. Homeostatic Imbalance • Disturbance of homeostasis • Increases risk of disease • Contributes to changes associated with aging • Control systems less efficient • If negative feedback mechanisms overwhelmed • Destructive positive feedback mechanisms may take over (e.g., heart failure)

26. Pass the Folder • Analyze scenarios to determine if homeostasis is being maintained.

27. Student should be able to….. • Differentiate between Anatomy and Physiology • List necessary life functions (8) • List survival needs (5) • Explain homeostasis and give examples of types of feedback • Quiz on vocab. Terms later this week

28. What do I want you to take away today? • Be able to: • Name the levels of structural organization that make up the human body and explain how they are related (6 of them) • Name the organ systems of the body and state the major function of each system • Remember Quiz Friday on Vocab. Terms

29. Levels of Structural Organization • Chemical- most simple level Atoms combine to form molecules • Cellular- made up of molecules Cells • Tissue Groups of similar cells • Organ Contains two or more types of tissues • Organ System Organs that work closely together for a common purpose • Organismal- highest level of structural organization All organ systems

30. Figure 1.1 Levels of structural organization. Slide 1 Organelle Atoms Molecule Smooth muscle cell Chemical level Atoms combine to form molecules. Cellular level Cells are made up of molecules. Smooth muscle tissue Cardiovascular system Tissue level Tissues consist of similar types of cells. Heart Blood vessels Blood vessel (organ) Smooth muscle tissue Connective tissue Epithelial tissue Organ level Organs are made up of different types of tissues. Organ system level Organ systems consist of different organs that work together closely. Organismal level The human organism is made up of many organ systems.

31. Organ System Overview • Integumentary System- skin • Skeletal System- provides framework (bones) • Muscular System- muscles • Nervous System- body control center • Endocrine System- produce hormones • Cardiovascular System- heart/blood vessels • Lymphatic System- lymph nodes

32. Organ System Overview • Respiratory- breathing; keeps blood constantly supplied with 02 • Digestive- breaks food down • Urinary- eliminates nitrogenous wastes from body • Reproductive- male /female; production of offspring

33. What do I want you to take away today? • Be able to: • Name the levels of structural organization that make up the human body and explain how they are related (6 of them) • Name the organ systems of the body and state the major function of each system • Remember Quiz Friday on Vocab. Terms

34. The Student Will Be Able To: • Demonstrate correct anatomical position • Differentiate between positional terminology • Complete Vocab. Terms Quiz

35. Bellwork • Complete Odd Organ Out Handout

36. Anatomical Position (refer to doodle definitions) • Standard anatomical body position • Body erect • Feet slightly apart • Palms facing forward • Thumbs point away from body • Always use directional terms as if body is in anatomical position • Right and left refer to body being viewed, not those of observer

37. Table 1.1 Orientation and Directional Terms (1 of 3) (refer to doodle definitions)

38. Table 1.1 Orientation and Directional Terms (2 of 3)

39. Table 1.1 Orientation and Directional Terms (3 of 3)

40. Group Work • Create a song, rap, chant, etc. with movements that correctly demonstrates the anatomical position and other positional terms. Refer to your definitions/notes for these terms. You must use a minimum of 6 vocabulary terms. • *The movements and word choice must be school appropriate! • We will perform your original creations before the end of class!

41. Practice • The heart is ________ to the arm. • The head is ________ to the neck. • The abdomen is _______ to the head. • The arms are ______ to the ribs. • The thigh is ______ to the knee. • The knee is _____ to the thigh.

42. Vocabulary Quiz • Get out your vocabulary and put everything else away. I will check your vocabulary before we start the quiz.

43. Bellwork • Describe in detail the correct anatomical position.

44. Objectives • Identify body cavities and regions • Review A&P concepts discussed in unit 1

45. Regional Terms (refer to note sheet) • Two major divisions of body • Axial • Head, neck, and trunk • Appendicular • Limbs • Regional terms designate specific areas within body divisions

46. Figure 1.7a Regional terms used to designate specific body areas. Cephalic Frontal Orbital Nasal Oral Upper limb Mental Acromial Cervical Brachial (arm) Antecubital Thoracic Sternal Antebrachial Axillary (forearm) Mammary Carpal (wrist) Abdominal Umbilical Manus (hand) Pollex Pelvic Inguinal (groin) Palmar Digital Lower limb Coxal (hip) Femoral (thigh) (genital) Pubic Patellar Crural (leg) Fibular or peroneal Pedal (foot) Thorax Tarsal (ankle) Abdomen Metatarsal Back (Dorsum) Digital Hallux Anterior/Ventral

47. Figure 1.7b Regional terms used to designate specific body areas. Cephalic Otic Occipital (back of head) Upper limb Acromial Cervical Brachial (arm) Olecranal Back (dorsal) Antebrachial Scapular (forearm) Vertebral Lumbar Manus (hand) Sacral Metacarpal Gluteal Digital Perineal (between anus and external genitalia) Lower limb Femoral (thigh) Popliteal Sural (calf) Fibular or peroneal Pedal (foot) Calcaneal Back (Dorsum) Plantar Posterior/Dorsal

48. Body Planes and Sections • Body plane • Flat surface along which body or structure may be cut for anatomical study • Sections • Cuts or sections made along a body plane

49. Body Planes • Three most common • Lie at right angles to each other • Sagittal plane (midsagittal) • Frontal (coronal) plane • Transverse (horizontal) plane

50. Sagittal Plane • Sagittal plane • Divides body vertically into right and left parts • Produces a sagittal section if cut along this plane • Midsagittal (median) plane • Lies on midline