Intro to Medical Science

Transcription

1 Intro to Medical Science

2 Unit 1: Objectives 1. Review the basic functions of living organisms 2. Define Anatomy and Physiology and gain an understanding of the relationship between the two 3. Identify major levels of organization in living organisms 4. Understand the basic functions of the various systems in the body 5. Explain the significance of Homeostasis 6. Use anatomical terms to describe body orientation 7. Identify major cavities of human body and their multiple subdivisions

3 Characteristics of Life Six common characteristics of living things

4 Characteristics of Life 1. Cellular organization- The cell is the smallest unit that can be alive. The cells within a multicellular organism are arranged into tissues and organ systems 2. Energy requirement- living organisms carry out cellular respiration which converts energy in food to a form that is useable by cells for life processes

5 Characteristics of Life 3. Interaction with the environment- living organisms depend on the environment for food and nutrients. Organisms must maintain a stable internal environment through homeostasis 4. Reproduction- living organisms have the ability to reproduce more of their own kind

6 Characteristics of Life 5. Adaptation- Populations of living organisms are able to adapt to changing environmental conditions 6. Growth and Development- Organisms grow from a single cell as an egg, to an adult with millions (or more) cells.

7 Anatomy and Physiology anatomy (n.)-the study of internal and external structures and the physical relationship between body parts. physiology (n.)-the study of how living organisms perform their functions.

8 Major Levels of Organization Atom Molecule Cells Tissue Organ Organ system Organism

9 Major Levels of Organization Atom and Molecule- chemical level of organization Cells- smallest unit of life Tissue- similar cells working together Organ- two or more different tissues work together to perform specific functions Organ system- multiple organs work together to perform specific functions Organism- organ systems working in sync to create homeostasis

10 Major Systems of the Body Integumentary- skin, nails, hair Protects and regulates temperature

11 Major Systems of the Body Skeletal- bones and cartilage Support, protection, blood cell formation

12 Major Systems of the Body Muscular- muscle Movement, support, creates heat

13 Major Systems of the Body Nervous system- Brain, spinal cord, nerves Responds to stimuli, coordinates organ systems

14 Major systems of the body Endocrine system- glands Directs long term changes in organ systems

15 Major systems of the body Cardiovascular system- heart, blood vessels Transportation of materials through body

16 Major systems of the body Lymphatic system- lymph nodes, spleen Immune system

17 Major systems of the body Respiratory system- lungs Delivers air to gas exchange sites

18 Major systems of the body Digestive system- stomach, intestines, liver Processes food and absorbs materials

19 Major systems of the body Urinary system- kidneys Eliminates water, wastes, etc.

20 Major systems of the body Reproductive System Creates sex cells and hormones

21 Homeostasis The existence of a stable internal environment. Is it constant? NO!! Unless you are dead. It is constantly fluctuating

22 Homeostasis 3 Components to this regulation 1. Receptor/Sensor- detects the change (body is getting too warm) 2. Control center- receives and processes the signal from the receptor/sensor (usually the brain) and sends message to effector 3. Effectors- responds to the commands of the control center and reverses the initial change (skin pores begin to perspire and blood vessels dilate)

23 Homeostasis Response can be either opposition to stimulus or a Negative feedback loop Reinforcement of stimulus or a Positive feedback loop

24 Example: Household Thermostat Temperature Set point 68 degrees increases (stimulus) Temperature decreases Thermometer senses change (receptor) Thermostat turns AC on (control center)

25 Set point 98.6 Degrees Outside temperature Decreases (stimulus) Body temp stays constant Detected by temperature receptors in skin (receptor) Muscle fibers contract generate heat (effectors) Brain processes info and sends signal to Body (control center)

26 Homeostasis Positive feedback loop- intensifies stimulus Severe cut: signals more clotting factors Labor: signals more contractions

27 Homeostasis Negative feedback loop- opposes the initial stimulus Regulation of body temp. Regulation of blood glucose levels Regulation of CO2 levels in blood

28 The Language of Anatomy Anterior front side The navel is on the anterior surface of the trunk. Ventral belly side The legs are located on the ventral side of the mink. Posterior back side The shoulder blade is located posterior to the rib cage. Dorsal back side The breathing hole in dolphins is located on the dorsal side.

29 The Language of Anatomy Cephalic the head The cephalic border of the pelvis is superior to the thigh. Superior above; toward the head The nose is superior to the chin. Caudal Tail The hips are caudal to the waist. Inferior Below The knees are inferior to the hips.

30 The Language of Anatomy Medial Lateral Toward the midline of the body Away from the midline of the body The medial surfaces of the thighs may be in contact. Moving medially from the arm across the chest brings you to the sternum. Moving laterally from the nose brings you to the eyes. Proximal Distal Toward an attached base Away from an attached base The thigh is proximal to the foot. The fingers are distal to the wrist

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32 PLANES OF THE BODY Three different sectional planes 1. Transverse plane- divides body into superior and inferior sections Transverse Plane

33 PLANES OF THE BODY 2. Frontal plane/coronal Plane- divides body into anterior and posterior sections

34 PLANES OF THE BODY 3. Sagittal plane- divides the body into left and right sections

35 Fun WebSite

36 Quadrants of Abdomen Abdominopelvic quadrants- four segments that intersect at umbilicus Right upper quadrant Right lower quadrant Left upper quadrant Left lower quadrant

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38 Quadrants of abdomen For more precise regional distinctions, there are nine abdominopelvic regions used to describe the location of internal organs

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40 Body Cavities Serve two functions 1. Protect organs from accidental shocks and cushion them during walking, running, jumping, etc. 2. Permit significant changes in size and shape of visceral organs

41 Body Cavities Two main body cavities formed during embryological development each has various sub cavities

42 Body Cavities 1. Dorsal Body Cavity Cranial cavity- encloses the brain Spinal cavity- surrounds the spinal cord

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44 Body Cavities 2. Ventral body cavity Thoracic cavity Pleural cavity (lungs) Pericardial cavity (heart) Abdominopelvic cavity Abdominal cavity Pelvic cavity

45 Body Cavities Mediastinum- not considered body cavity, yet houses pericardial cavity, thymus gland, trachea, and esophagus

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