Body Organization/ Functions

CH 1

Levels of structural organization:

1. chemical

2. cellular

3. tissue

4. organ

5. system

6. organismal

1.Chemical Level

• atoms, molecules, and organelles

Cellular level

single cell

Tissue leve

groups of similar cells

Organ level

contains 2+ types of tissues

Organ system level

organs that work closely together

Organismal level

all organ systems combined to make the whole organism

-the whole

Gross anatomy

• study of large, visible structures

  • Regional anatomy: structures in a particular area of the body

  • System anatomy: looks at just one system

  • Surface anatomy: looks at internal structures as they relate to overlying skin (visible muscle masses or veins seen on surface)

Microscopic anatomy

• study of structures too small to be seen by naked eye

• Cytology: microscopic study of cells

• Histology: microscopic study of tissues

Integumentary system

• C: skin, hair, nails, sweat glands, oil glands

• F: protects body, reg temp, eliminate waste, helps make vitamin D, detects sensations

Skeletal system

• C: bone and joints of the body and their cartilage

• F: support and protect the body, provides surface area for muscle attachments, aids body movements, stores minerals and fats

Muscular system

• C: skeletal muscle tissues-usually attached to bones

• F: participate in body movements, maintaining posture, producing heat

Nervous system

• C: brain, spinal cord, nerves and eyes/ears(special sense organs)

• F: generates action potentials to reg body activity, detects changes in body's internal/external environment, interprets changes and responds by causing muscular contraction 

Endocrine system

• C: hormone producing glands and hormone producing cells in several other organs

• F: regulates body activity by releasing hormones 

Cardiovascular system

• C: blood, heart, vessels

• F: heart pumps through blood vessels: blood carries oxygen and nutrients to cells and carbon dioxide and wastes away from cells and helps regulate acid-base balance, temp, water content of body fluids, helps defend again disease and repairs

Lymphatic/immune system

• C:  lymphatic fluid and vessels; spleen, thymus, lymph nodes, tonsils- cells that carry out immune responses

• F: returns proteins and fluids to blood; carries lipids from GI tract to blood; B and T cells that protect against diseas-causing microbes

Respitory system

• C: lungs and air passageways pharynx, larynx, trachea, bronchial tubes

• F: transfers oxygen from inhaled air to blood and carbon dioxide from blood to exhaled air;helps regulated acid base balance of body fluids; produce sounds

Digestive system

• C: mouth, pharynx, esophagus, stomach, small large intestines, rectal

• F: physical and chemical breakdown of food, absorbing nutrients, eliminating waste

Urinary system

• C: kidneys, ureters, urinary bladder, urethra

• F: produces stores and eliminates waste and regulates volume and chemical comp of blood; helps regulate production of red blood cells; maintains mineral balance and acid base of body fluids

Reproductive system

• C: gonads(testes in male and ovaries in females) and associated organs

• F: gonads produce gametes to unite to form a few organism; release hormones that regulate reproduction and other processes

To be alive…

1. Metabolism

2. Responsiveness

3. Movement

4. Growth

5. Differentiation

6. Reproduction

7. Homeostasis : condition of equilibrium, or balance, in the body’s internal environment

   • Maintained by body’s regulatory processes

Control of homeostasis

1. receptor- fills the narrow spaces between cells of tissues is known as interstitial fluid

2. control center- sets the range or set point within which a controlled condition should be maintained, and generates output commands when they are needed

3. effector- receives output from the control center and produces a response

• When homeostasis is disrupted, it may result in disease, disorder, or even death

Negative feedback system

reverses a change in a condition

• ex: BP inc →brain signals heart/vessels → heart rate decreases + vessels dilate → BP decreases

Positive feedback system

strengthens a change in a condition

• Labor contractions → cervix stretches → brain releases oxytocin → stronger contractions → more stretching → continues until birth

homeostasis

is the maintenance of relatively stable conditions in the body’s internal environment

intracellular fluid

fluid within cells

extracellular fluid

fills the narrow spaces between cells of tissues is known as interstitial fluid