Regulation and Homeostasis in the Human Body: Overview

1. Regulation and Homeostasis in the Human Body: Overview

2. 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 energyGet building materials Get rid of waste Keep away disease Respond to changing environment Reproduce

3. 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

4. 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

5. 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

6. 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

7. 4. Circulatory System Structures: Heart, Blood vessels, blood Functions: Brings oxygen, nutrients, and hormones to cells; fights infection; regulates body temperature

8. 5. Respiratory System Structures: Nose, pharynx, larynx, trachea, bronchi, bronchioles, lungs Functions: Provides oxygen needed for cellular respiration and removes carbon dioxide from body

9. 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

10. 7. Excretory System Structures: Skin, lungs, kidneys (nephrons), ureters, urinary bladder, urethra Functions: Removes waste products of metabolism from the body

11. 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

12. 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

13. 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

14. Support and Motion Functions of the SKELETAL AND MUSCULAR SYSTEM

15. 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.

16. A.Skeletal System Skull Clavicle Sternum Scapula Humerus Ribs Radius Vertebral column Pelvis Ulna Carpals Metacarpals Phalanges Femur Patella Fibula Tibia Tarsals Metatarsals Phalanges There are 206 bones in the adult human body. These bones provide a system of supports and levers on which muscles can produce movement

17. Bones 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 Figure 36-3 The Structure of Bone Bone Marrow

18. 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. Clavicle Figure 36-4 Freely Movable Joints and Their Movements Section 36-1 Ball-and-Socket Joint Pivot Joint Elbow Hinge Joint Saddle Joint Knee

19. Muscle Tendon Femur Patella Bursa Ligament Cartilage Fat Fibula Tibia Knee Joint Section 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

20. 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.

21. Figure 36-7 Skeletal Muscle Structure Skeletal muscles are made up of clusters of filaments of proteins known as actin and myosin which control muscle contraction and relaxation Section 36-2

22. Figure 36-8 Muscle Contraction During Muscle contraction Actin filaments slide over myosin filaments shrinking the muscle

23. Energy for muscle contraction is supplied by ATP

24. 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

25. Figure 36-11 Opposing Muscle Pairs Skeletal muscles work in opposing pairs. When one muscle contracts, the other relaxes. Section 36-2 Movement Biceps (relaxed) Biceps (contracted) Movement Triceps (contracted) Triceps (relaxed)

26. Nutrition and Waste Removal 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.

27. Overview of Nutrients • 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.

28. 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)

29. 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.

30.  Food Guide Pyramid A Balanced Diet Fats Sugars

31. C. The Digestive System Mouth Pharynx Salivary Glands Esophagus Liver Stomach Pancreas behind stomach Gallbladder Large Intestine Small Intestine Rectum

32. 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

33. 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. Section 38-2 Liver Bile Duct Gallbladder Pancreas Doudenum

34. 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

35. 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. Section 38-2 Small Intestine Villus

36. 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.

37. 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.

38. 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) Section 38-3 Kidney Nephron Bowman’s Capsule

39. 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. Artery Vein Kidney Ureter Urinary Bladder Urethra

40. Other important parts of the bodies excretory system • The skin excretes excess water and salts • The lungs excrete carbon dioxide produced from respiration Both of these body organs serves multiple functions in the human body.

41. The Respiratory System links to the Circulatory System to provide cells with oxygen and remove carbon dioxide Figure 37-13 The Respiratory System Section 37-3 Bronchi branch to air sacs known as aveoli where gas exchange occurs

42. Gas Exchange in the lungs occurs through the process of Alveoli Section 37-3 Bronchiole DIFFUSION High concentration of oxygen (O2) moves out of lungs into blood to balance concentration. CO2 does the opposite (moves from blood to lungs) Capillary

43. The Lungs are only air sacs. In order for them to move they must work together with a muscle known as the Diaphragm Figure 37-15 The Mechanics of Breathing Section 37-3 Air inhaled Air exhaled Rib cage lowers Rib cage rises Diaphragm Diaphragm Exhalation Inhalation

44. Breathing is not an entirely voluntary process. While you have control of breathing so that you can briefly hold your breath or blow up a balloon, your body will not allow you not to breathe. The brain has control over the diaphragm if the level of carbon dioxide in the blood rises to high.

45. The circulatory system works together with several other body systems to bring needed supplies to cells which cannot move. The circulatory system is a delivery system that consists of the following: • The Heart • Blood Vessels • Blood

46. The Heart: The heart is about the size of a clenched fist. On average the heart contracts about 72 times a minute, pumping about 70 milliliters of blood with each contraction. The entire circulatory system including Heart has structures which prevent oxygen rich blood and oxygen poor blood from mixing. All blood is really red but oxygen poor blood is shown as blue in pictures for ease.

47. The heart has four main chambers with valves that separate each to prevent backflow Pulmonary Artery Oxygen poor blood to lungs Left Atrium Left Ventricle

48. The heart acts as two pumps. One for sending oxygen poor blood to the lungs and the other for sending oxygen rich blood to the body.

49. The heart’s contractions are controlled by a small group of cardiac muscle cells known as the sinoatrial node. These are the pacemakers of the heart. These cells send an electrical message from the atrium to the ventricles to contract Sinoatrial Node Conducting Fibers Atrioventricular node

50. Blood moves through 3 different types of vessels: Arteries – Carry oxygen rich blood away from the heart Capillaries – Tiny vessels only one cell thick. Bring oxygen and nutrients to the cells. Remove waste products. Veins – Carry blood back to the heart with wastes VEIN ARTERY CAPILLARIES