Unit 9 Human Body Part 1 Body Organization

Unit 9: Human Body Part 1 ~ Body Organization and Systems Overview Mrs. Howland Biology 10 Rev. Feb 2016

Lesson Objectives: Learners will be able to… Identify organs and the system to which they belong. Identify the functions of the various systems of the human body. Explain how cells and tissues are specialized for specific functions. Explain how the different organs within an organ system work together to perform a common function. Explain how the different organ systems work together to maintain homeostasis.

How do parts of the human body work together to maintain life? Levels of Organization

Organization of the Body A CELL is the basic unit of structure and function in a living thing

Cells of the Human Body

Cells of the Human Body Microscope view Epithelial cells Blood cells Neuron Columnar epithelial cells with Goblet cells Bone cells Skeletal muscle cells Cardiac muscle cells

Organization of the Body TISSUES are groups of cells with similar structure and function

Tissues of the Human Body FOUR (4) Basic types of tissue: CONNECTIVE tissue EPITHELIAL tissue MUSCLE tissue NERVOUS tissue

Tissues of the Human Body

Organization of the Body Organs are groups of tissues arranged to work together to perform a common function

Organization of the Body Organ systems are a group of organs that work together (are interrelated) to perform one or more functions for the body

HUMAN BODY SYSTEMS Organization of the body relates how the structure of the body affects its function à You’ll soon see that this is a common theme!! Integumentary System Excretory System Skeletal System Digestive System Muscular System Respiratory System Nervous System Endocrine System Circulatory System Reproductive System Lymphatic/Immune System

Integumentary System MAJOR STRUCTURES: SKIN Hair Subcutaneous tissue Glands FUNCTION: External barrier to other organisms, viruses, and chemicals; thermoregulation.

Skeletal System MAJOR STRUCTURES: Bones Cartilage Ligaments Bone marrow FUNCTION: Support and move body; protect internal organs; mineral storage (calcium!); blood formation (cells!)

Muscular System MAJOR STRUCTURES: Muscles Tendons FUNCTION: Locomotion (movement!); heat production

Nervous System MAJOR STRUCTURES: Brain Spinal cord Nerves (eyes, ears) FUNCTION: Coordinate activities of other organ systems; respond to sensations

Circulatory System MAJOR STRUCTURES: Heart Blood (blood cells and plasma) Blood vessels (veins, arteries, capillaries) FUNCTION: Transport oxygen and nutrients to body tissues; remove waste products (carbon dioxide, etc. !)

Excretory System MAJOR STRUCTURES: Kidneys Urinary bladder Urethra FUNCTION: Elimination of wastes; regulate p. H and volume of blood

Digestive System MAJOR STRUCTURES: Stomach Intestinal tract Liver Pancreas Esophagus Salivary glands FUNCTION: Processes foods; absorption of nutrients into the body

Respiratory System MAJOR STRUCTURES: Lungs Trachea Larynx Pharynx Nasal cavities FUNCTION: Exchange of oxygen (O 2) and carbon dioxide (CO 2) gasses to/from blood

Endocrine System MAJOR STRUCTURES: Pituitary gland Parathyroid gland Thyroid gland Adrenal gland Thymus Pancreas Gonads FUNCTION: Regulates body functions using hormones (chemical signal molecules)

Reproductive System MAJOR STRUCTURES: FEMALES: Ovaries Uterus Mammary glands MALES: Testes Prostate gland FUNCTION: Produces germ cells (eggs and sperm); environment for growth of fetus (females); organism reproduction

Lymphatic/Immune System MAJOR STRUCTURES: Spleen Lymph nodes Thymus Lymphatic vessels FUNCTION: Returns tissue fluid to blood; defense against foreign organisms

HOMEOSTASIS Homeostasis = A means by which an organism maintains a constant internal environment EXAMPLES: Thermoregulation (body temperature) Fluid levels p. H ( acid/base levels) Glucose levels Calcium levels

Negative & Positive Feedback Mechanisms NEGATIVE feedback mechanisms = Response reverses a change in the specific, controlled condition Maintains HOMEOSTASIS Example: Thermoregulation Most common type of feedback mechanism in living organisms, particularly humans POSITIVE feedback mechanisms = Response stimulates a change in the specific, controlled condition Does NOT maintain homeostasis Example: Release of oxytocin to move along labor Not common in organisms

SENSOR RECEPTOR that detects changes in a variable and sends a signal to the integrator. Constantly monitoring. Responds to significant change INTEGRATOR CONTROL CENTER that integrates (puts together) information from the sensor and the “set point” for the specific variable EFFECTOR MECHANISM that has an “effect” on the variable. It re-adjusts the variable back to its set point. Homeostasis

THERMOREGULATION What happens when your body gets too cold or too warm? “Set point” for body temperature is ~37 degrees C Temperature regulation is monitored in the brain by the hypothalamus EFFECTOR mechanisms include: Shivering using body muscles to adjust temperature back up Sweating using sweat glands in skin to adjust temperature back down

Thermoregulation ~ temp too low

Thermoregulation ~ temp too high

Thermoregulation Example of homeostasis SENSOR: Temperature receptors in skin INTEGRATOR: Brain (hypothalamus) EFFECTOR: Sweat glands or muscles, depending on the mechanism that is triggered