Organs and Organ Systems

Textbook: Chapter 10

Organ

2+ tissues working together for a function

Organ System

Group of organs with common function(s)

Integumentary System (skin)

• Protects underlying tissues

• Provides skin sensation

• Helps regulate body temp.

• Synthesizes vitamin D

Skeletal System

• Attachment for muscles

• Protects organs

• Stores calcium and phosphorus

• Produces blood cells

Muscular System

• Moves body and maintains posture

• Internal transport of fluids

• Generation of heat

Nervous System

Regulates and integrates body functions via neurons

Endocrine System

Regulates and integrates body functions via hormones

Cardiovascular System

• Transports nutrients, respiratory gases, wastes, and heat

• Transports immune cells and antibodies

• Transports hormones

• Regulates pH

Lymphatic System

• Returns tissue fluids to bloodstream

• Protects against infection and disease

Respiratory System

Exchanges respiratory gases with the environment

Digestive System

• Physical and chemical breakdown of food

• Absorbs, processes, stores food

Urinary System

Maintains constant internal environment through the excretion of nitrogenous waste

Reproductive System

• Produces and secretes hormones

• Produces and releases egg and sperms cells

• Houses embryo/fetus (females only)

• Produces milk to nourish offspring (females only)

Internal Body Cavities

Protect vital organs and allow them to slide past one another and change shape (2 types)

Ventral Cavity

Thoracic (lungs and heart), abdominal (digestive, urinary, and reproductive)

Dorsal Cavity

Cranial (brain) and spinal (spinal cord)

Membranes

• Mucous: line external openings

• Serous: line thoracic/abdominal cavities

• Synovial: line movable joints

• Cutaneous: skin

The Skin

• Our largest organ: protects, prevents water loss, regulates temp., synthesizes vitamin D, senses stimuli

• Color influenced by blood flow and melanin

Skin Cancer (overexposure to the sun)

• Basal Cell Carcinoma: most common, arises in the rapidly dividing cells of the deepest layer of the epidermis

• Squamous Cell Carcinoma: 2nd most common, arises in the newly formed skin cells as they flatten and move towards the skin surface

• Melanoma: least common and most dangerous type of skin cancer

Homeostasis

Maintenance of stable internal conditions (involves nervous and endocrine systems)

• Negative feedback reverses change (ex: blood sugar regulation)

• Positive feedback amplifies change (ex: childbirth contractions)

Thermoregulation (Hypothalamus and Body Temp.)

• Receptors: thermoreceptors

• Control center: hypothalamus

• Effectors: sweat glands, blood vessels in the skin, and skeletal muscles

  • Ex:

    • Hyperthermia: abnormally elevated body temp.

    • Hypothermia: abnormally low body temp.