Chapter 6 Lesson 1

Levels of Organization

Cells tissues organs organ systems

AND FINALLY THE ORGANISM

Lesson 6.1

Cells – smallest living unit

Tissue – group of cells that function together to do a job

Organ – group of tissues that function together to do a job

Organ system – group of organs that function together to do a job

Body Cavities

There are 4 main body cavities:

1. Cranial cavity – contains the brain

2. Thoracic cavity – chest area includes heart, lungs,windpipe, esophagus

Body Cavities

There are 4 main body cavities:1. Cranial cavity 2. Thoracic cavity

3. Abdominal cavity – stomach, spleen, kidney, intestines

4. Spinal cavity – holds the spinal cord

There are 11 Organ Systems in the Human Body

11 Organ Systems:

1. Circulatory system: Organs include heart, arteries, veins, and capillaries

Transports substances throughout the body

2. Immune system: Defends the body against bacteria, viruses, and other invadersMost important part are white blood cells made in bone marrowAlso includes spleen and tonsilsSubdivision of immune system is the lymphatic system which filters lymph from blood through lymph nodes

3. Respiratory system: Functions to supply body with oxygen and rid of carbon dioxideIncludes nose, nasal passages, pharynx, larynx, trachea, bronchial tubes and lungs

4. Digestive system: Functions to digest or mechanically and chemically break down the food into usable molecules that are absorbed into the blood stream

Includes mouth, esophagus, stomach, small and large intestines, rectum, and anus

5. Excretory system: Functions to rid the body of metabolic waste

Includes sweat glands, kidneys, urethra, bladder

6. Nervous system: Functions to coordinate activities in the body through electrochemical means

Includes sense organs, nerves, brain, and the spinal cord

7. Endocrine system: Functions to coordinate activities in the body through chemical means

Chemicals used are called hormones

Includes endocrine glands such as pituitary gland, thalamus, thyroid, parathyroid, etc.

8. Integumentary System: Functions to provide communication between body and outside environment, protects the body from the world around us

Includes the largest organ of the body the skin

9. Skeletal System: Functions to support and protect the body, produces red and white blood cells, stores minerals such as calcium

Includes the 206 bones

10. Muscular System: Functions to provide movementTwo types of muscle include voluntary and involuntary

Voluntary - have conscious controlInvoluntary – unconscious control

11. Reproductive System:

Functions to continue the human race

Heavily regulated by the endocrine system

Includes many organs such as the ovaries, uterus, etc.

Note: Odds and Ends

Remember:

Arteries pump blood away from the heart.

Veins pump the blood to the heart.

Arteries and veins end in capillaries.

Note: Odds and Ends

Remember:

Kidneys filter the blood removing excess water and metabolic waste.

Diaphragm – muscle that separates the thoracic and abdominal cavities. When it contracts and relaxes it forces air in and out of lungs.

Mouth is where digestion begins and food is prepared.

Esophagus – muscular tube to stomach, pushes food along by wave-like contractions called peristalsis.

Stomach – stores food

Small intestine – most digestion and absorption

Large intestine – water reclaimed

Rectum – undigested food stored

Lesson 6.2 Tissues

There are 4 types of tissues:

1. Epithelial – skin and lines organs and body parts

Lesson 6.2 Tissues

There are 4 types of tissues:

1. Epithelial – skin and lines organs and body parts

2. Connective – holds things together, includes bone, tendons, ligaments, blood, fat

Lesson 6.2 Tissues

There are 4 types of tissues:

1. Epithelial – skin and lines organs and body parts2. Connective – holds things together, includes bone, tendons, ligaments, blood, fat

3. Muscle – movement

Three typesof muscle

tissue

1. cardiac

3. striated

2. smooth

Lesson 6.2 Tissues

There are 4 types of tissues:

1. Epithelial – skin and lines organs and body parts2. Connective – holds things together, includes bone, tendons, ligaments, blood, fat3. Muscle – movement

4. Nerve – controls organs and coordinates functions

Lesson 6.2 Tissues

4 types of tissue fluids: (66% is water)1. Blood = major body fluid

2. Cerebrospinal fluid = bathes brain and spinal chord

Lesson 6.2 Tissues

4 types of tissue fluids:1. Blood = major body fluid2. Cerebrospinal fluid = bathes brain and spinal chord

3. Interstitial fluid = surrounds the cells in the tissue and is picked up by the lymphatic system to filter out invaders

4. Lymph fluid = interstitial fluid picked up by lymphatic system

Lesson 6.2 Tissues

Membranes are thin coverings that line.4 types of membranes in the body:1. Serous – line enclosed body cavities that don’t open to outside

2. Mucous – line cavities that open to the outside

Lesson 6.2 Tissues Membranes are thin coverings that line.

4 types of membranes in the body:1. Serous – line enclosed body cavities that don’t open to outside2. Mucous – line cavities that open to the outside

3. Cutaneous – skin

4. Synovial – line the synovial joints (like knee)

Lesson 6.2 Tissues

Matrix – substance between the cellsNote: Tissues are made of individual cells and the matrix these cells produce which is found between the cells.

Examples of tissues with matrix:cartilage, bone, and blood (plasma)

Lesson 6.2 Tissues

Matrix – substance between the cellsNote: Tissues are made of individual cells and the matrix these cells produce which is found between the cells.

Ex. Bone is a connective tissue made of bone cells such as osteoblast and osteocytes that lay down a matrix of minerals such as calcium and protein fibers called collagen.

Osteon

Bone Tissue

Bone cellmatrix

Lesson 6.2 Tissues

Vestigial organs are organs that we do not understand their functions.Evolutionist once claimed these were organs no longer needed.Ex. Parathyroid, appendix The list of vestigial organsin humans has shrunk from 180 in 1890 to 0 in 1999.

Two vestigial organs and their known functions:

Appendix – known immune system function

Parathyroid – calcium regulation in blood and bones