Post on 26-Dec-2015
How do Humans and other complex mammals maintain homeostasis? They must carry out all needed life functions in a coordinated way.
What does our species need to accomplish?
Growth Repair of injuries
Get energy Get building materials
Get rid of waste
Keep away disease
Respond to changing environment
Reproduce
Eleven Body Systems work together to maintain homeostasis and carry out these tasks:
1. Nervous System 2. Endocrine System
3. Lymphatic System 4. Circulatory System
5. Respiratory System 6. Digestive System
7. Excretory System 8. Skeletal System
9. Muscular System 10. Integumentary System
11. Reproductive System
1. Nervous System:
Structures: Brain, Spinal Cord, Peripheral Nerves, Neurons (Cells of nervous system)
Functions: Coordinates the body’s response to changes to internal and external environment
2. Endocrine System – Hormone System
Structures: Glands - Hypothalmus, pituitary, thyroid, parathyroids, adrenals, pancreas, ovaries (in females), testes (in males)
Functions: Produce Hormones. Controls growth, development, metabolism, and reproduction
3. Lymphatic System – Immune System
Structures: White blood cells, thymus, spleen, lymph nodes, lymph vessels
Function: Helps protect the body from disease; collects fluid lost from blood vessels; returns the fluid to the circulatory system
4. Circulatory System
Structures: Heart, Blood vessels, blood
Functions: Brings oxygen, nutrients, and hormones to cells; fights infection; regulates body temperature
5. Respiratory System
Structures: Nose, pharynx, larynx, trachea, bronchi, bronchioles, lungs
Functions: Provides oxygen needed for cellular respiration and removes carbon dioxide from body
6. Digestive System
Structures: Mouth, pharynx, larynx, esophagus, stomach, liver, pancreas, small and large intestines,
Function: Breaks down foods into simple molecules that can be used by the body for respiration and building cells
7. Excretory System
Structures: Skin, lungs, kidneys (nephrons), ureters, urinary bladder, urethra
Functions: Removes waste products of metabolism from the body
8. Skeletal System
Structures: Bones, cartilage, ligaments, tendons
Functions: Supports the body; protects internal organs; allows movement; stores mineral reserves; provides a site for blood formation
9. Muscular System
Structures: Skeletal muscle, smooth muscle, cardiac muscle
Function: Works with skeletal system to produce voluntary movement; helps circulate blood and move food through the digestive system
10. Integumentary System (Skin)
Structures: Skin, Hair, Nails, Sweat and Oil Glands
Functions: Serves as a barrier against infection and injury; Helps to regulate temperature; Protects against UV light
Structures:
Female- Uterus, Fallopian tubes, ovary, cervical canal, cervix, vagina
Male – Penis, Vas Deferens, Prostate, Epididymis, Testes, Scrotal Sac, Seminal Vesicle
Function: Produces reproductive cells; in females nurtures and protects developing embryo
11. Reproductive System
How does the human body move from place to place and have the ability to run, blink or build things?
These things are all made possible by the skeletal and muscular systems.
Skull
Sternum
Ribs
Vertebral column
Metatarsals
Metacarpals
Phalanges
ClavicleScapula
Humerus
RadiusPelvisUlnaCarpals
Femur
Patella
FibulaTibiaTarsals
Phalanges
A. Skeletal System
There are 206 bones in the adult human body. These bones provide a system of supports and levers on which muscles can produce movement
Figure 36-3 The Structure of BoneBones are a solid network of living cells and protein fibers that are surrounded by calcium deposits. Bones contain blood vessels and cavities containing marrow. Red marrow produces red blood cells, white blood cells and platelets
Bone Marrow
Ball-and-Socket Joint
Hinge Joint
Pivot Joint
Saddle Joint
Clavicle
Figure 36-4 Freely Movable Joints and Their Movements
Section 36-1
Joints are places where one bone attaches to another. Each type of joint is designed to allow movement without damaging the other bones. Joints in the skull allow no movement, joints in the spine allow a small amount of movement and those shown below allow movement in one or more directions.
Knee
Elbow
Muscle
Tendon
Femur
PatellaBursaLigament
Cartilage
Fat
Fibula
Tibia
Knee JointSection 36-1
Ligaments are a tough connective tissue that attach bones to bones
Tendons are connective tissue which attach bones and muscles to allow bones to move
B. The Muscular System
More than 40% of the average human is muscle. Muscles are involved in both voluntary actions and involuntary actions. Three types of muscles cells are:
•Skeletal – Attached to bones for voluntary actions and controlled by the central nervous system
•Smooth – Found in the digestive tract and the blood vessels to move food and blood. Control involuntary actions (you do not decide for them to work)
•Cardiac – Heart muscle cells are involuntary.
Figure 36-7 Skeletal Muscle Structure
Section 36-2Skeletal muscles are made up of clusters of filaments of proteins known as actin and myosin which control muscle contraction and relaxation
Nervous system cells known as motor neurons are attached to skeletal muscle cells to control the voluntary movement.
Threadlike Nerve or neuron
Axon or junction
Figure 36-8 Muscle Contraction
During Muscle contraction Actin filaments slide over myosin filaments shrinking the muscle
Movement
MovementBiceps
(relaxed)
Triceps (contracted)
Biceps (contracted)
Triceps (relaxed)
Figure 36-11 Opposing Muscle Pairs
Section 36-2Skeletal muscles work in opposing pairs. When one muscle contracts, the other relaxes.
How does the human body take in required nutrients and get rid of wastes?
The Digestive and Excretory Systems are responsible for bringing in food and getting rid of the leftovers.
Nutrition and Waste Removal
Food supplies the raw materials for building molecules your body needs, such as:
• enzymes
• Lipids in cell membranes
• DNA
Food contains 45 substances your body needs but cannot manufacture.
Overview of Nutrients
The nutrients your body needs are water, carbohydrates, fats, proteins, vitamins and minerals.
WATER – Most of the bodies reactions take place in water. Humans need an average of 1 liter of water a day. Dehydration causes many problems throughout the body.
CARBOHYDRATES – Sugars and starches are used by the body to provide the simple sugars needed for Respiration (energy)
FATS- Deposits of fats protect body organs, insulate the body and store energy, make up cell membranes and coat the nervous system cells
PROTEINS – Supply the raw materials for growth and repair in the form of enzymes
VITAMINS – Organic molecules that work with enzymes to control body processes.
MINERALS – Inorganic nutrients that are needed in small amounts. Calcium is needed to build bones, Iron is needed for red blood cells.
C. The Digestive System
Pharynx
Esophagus
Liver
Gallbladder
Rectum
Mouth
Salivary Glands
StomachPancreas behind stomach
Large Intestine
Small Intestine
The Process of Digestion: The path of food
Each organ of the digestive system helps convert foods into simpler molecules that can be absorbed and used by the cells of the body.
Teeth – Cut, Crush and tear food
Salivary glands – Moisten food to make it easier to chew and pass through the system, enzymes break down starches
Esophagus – Tube from mouth to stomach connected by Pharynx. Works by contraction of the smooth muscles known as peristalsis.
Stomach – Muscular sac that churns and mixes food with acid
Section 38-2
As food leaves the stomach it travels into the small intestine through the doudenum, and it mixes with with enzymes and digestive fluids from the liver, gallbladder and pancreas.
Liver
Gallbladder
Doudenum
Bile Duct
Pancreas
. Chemicals from the pancreas breakdown carbohydrates, proteins, lipids and nucleic acids. In addition chemicals from the pancreas produce substances which neutralize stomach acid.
If the acid travels too far without being neutralized it will change the shape of enzymes and cause problems in the body.
The Liver makes bile which acts like a detergent to break down fat. The gall bladder is a storage area for the bile
Small Intestine
Villus
Section 38-2
The small intestine absorbs nutrients from the digestive systems and transfers many of the nutrients to the circulatory system. The small intestine is lined with small fingerlike projections known as villi which designed to have a large surface area for this task.
Large intestine (Colon)
Food that enters the large intestine is nutrient-free. Usable nutrients have been absorbed leaving water and undigestible substances. The large intestine removes water from the waste. Once water is eliminated the solid waste passes out of the body through the rectum.
The appendix is located just below the entry to the large intestine. In many animals it
helps digest difficult materials such as cellulose. In humans the appendix is not used for any purpose
in digestion. When it gets infected it is removed.
D. Excretory System:
In the process of obtaining nutrients and carrying out chemical reactions the human body produces wastes (CO2, Urea, Salts). If some of these wastes are not removed they could threaten homeostasis. Excess chemicals that are not toxic also need to be removed.
The skin, lungs and kidneys all function to get rid of excess or harmful products
produced in the body.
Kidney Nephron
Section 38-3
Kidneys contain millions of small filters called nephrons, which filter your entire blood supply every 45 minutes. Filtration takes place because blood pressure forces water, salt, glucose, amino acids and urea into structures known as Bowman’s capsules. (Protein and Blood are too large to enter)
Bowman’s Capsule
Processes of osmosis and active transport filter the useful materials from the waste (urine). Substances your body needs to keep are returned to the blood stream. Substances your body needs to get rid of are passed from the renal tubes to the urinary bladder.
Kidney
Urinary Bladder
Ureter
Urethra
Vein Artery