Transcript Chapter 4
Chapter 4 Body Systems 6th Grade Science How is the body organized? • The human body is made up of more than __ 75 trillion cells. living • Every cell is part of a __________ unit which makes up the body. • Cells work together and depend on each other to keep the body’s internal conditions in _______. balance • ___________processes take place in the cells Chemical to maintain internal conditions. Chemical Processes in Cells • Important life processes can only occur in the cells at a particular temperature range 37˚ C (98.6˚ F) ___________. • Cells in different parts of the body work together to maintain this internal _________. temperature • Cells are ___________ in a way that makes organized them efficient. • Approximately _______ cells could cover the 10,000 head of a pin. Levels of Organization • All cells are made up of the same basic structure (same basic parts). _______ • Each cell is adapted to perform a very specific ________. function • Cells are organized by the ________ that they function perform. • Similar cells that work together to perform a particular function in the body make up tissues _______. Cells, Tissues, Organs • Cells that can ________, contract or shorten make up ________ tissues muscle • Cells that carry ________ messages from one cell to another make up ________ tissue. nerve • The ________ is made up of _______ tissue. brain nerve • When two or more tissues work together they organ form an _________. • Example: Your heart is an ______ that is made up organ tissues (muscle, of many different types of ______. nerve) Organ Systems • • • • Cells are organized to form ___________. tissues Tissues are organized to form _________. organs Organs are organized to form _____________. Organ systems Examples of organ systems: Circulatory – ______________ Digestive – ______________ Endocrine – ______________ Excretaory – ______________ Immune – ______________ Muscular _______________ Nervous _______________ Reproductive _______________ Respiratory _______________ Skeletal ________________ System Function Circulatory Transports oxygen, nutrients, and cell wastes Digestive Breaks down foods into a form that the body can use Endocrine Controls internal conditions. Growth, development, and reproduction Excretory Removes wastes from the blood Immune Defends the body against pathogens Muscular Allows body movement and movement of substances within the body Nervous Controls the body movement, thought and behavior Reproductive Produces sex cells and offspring Respiratory Provides the oxygen and removes gas wastes from the blood Skeletal Provides body protection and support; interacts with muscles to allow movement Example: The Heart muscle cells that have • The heart is made up of _______ many __________ mitochondria to provide energy for the heart to beat constantly. • The arrangement of muscle cells in the heart tissues form heart ________ which allows the heart to contract and relax as it beats. organ • The heart itself is an _________ which is made up of muscle tissues, tissues that provide support and protection, and tissues that form its blood vessels. Blood cells • ______ blood cells carry oxygen throughout the Red body so that all cells can carry out life functions. White • ________ blood cells help to fight diseasecausing invaders that attack the body. • Although each person is unique, the structure and function of the cells, tissues, and organ are similar in some ways. • These similarities enable other human beings to donate blood and entire organs. Skeletal system • Bones are ________ that make up the make up organs the skeletal system. • Bones are made up of living ________, as well as tissues minerals non-living _________ that are deposited by bone ________. cells The functions of the skeletal system: Provides support 1. ____________ Protects organs 2. _______________ Makes new blood cells 3. _________________ Stores important minerals 4. ___________________ Parts of the Bone • Parts of the bone: 1. Thin, tough outer covering on the surface of the bone tissue is living __________. Blood vessels in the bone carry blood which supplies 2. ___________ materials that none cells need. Blood also removes wastes that bone cells produce. ______ 3. _________ Compact bone is the hardest material in the human body, except for tooth enamel – it is made up of Bony tubes __________. 4. _______ Spongy bone tissue makes the bone lightweight. Red Marrow in the spongy bone makes new 5. __________ Red blood cells _______________. marrow stores fat. 6. Yellow __________ - As your body grows from an infant to an adult, cartilage the __________ (flexible material) is replaced by hard ________. bone -__________ and __________ make up the Cartilage bone skeletal system important organs Skull, ribcage, and back bone - Protect ______________ Calcium and phosphorous Bones store minerals such as _______________ Minerals in the Bones released • Minerals are __________ from the bone as the body needs them Calcium and phosphorus make bones hard and • _________________ strong. calcium • As people grow older, they lose _______ in their bones. The bones become weakened and can break easily. This is known as osteoporosis _______________. Joints • A __________is a place where two bones joint meet. cartilage • Flexible ___________ covers and protects the joints ends of bones at ________. shape • The _______ of cartilage surfaces and the way they fit together determines the _________ a direction joint can move. • Strong cords of tissue called ________ ligaments connect the bones in each joint Muscular system muscles allow • Bones support the body while ______ you to move. 600 • _________ muscles in the body make up about ________ of your body weight. 40-50% • Muscles and tissues that attach tem to the bone make up the _______________. Muscular system 3 • The body has _____ types of muscle tissues. 3 Types of Muscles • 1. _________ Muscle – muscle tissue in your Cardiac heart. Contracts without getting tired. Smooth • 2. __________ Muscle – found in the organs of the digestive system and blood vessels. • Cardiac and Smooth Muscles are INVOLUNTARY!! They work automatically to control movements inside your body. • 3. _________Muscles – voluntary muscles Skeletal that move your arms and legs Movement • All muscles can contract but only ________ skeletal muscles are responsible for ___________. movement Bones • ________ and _______ work together to muscles move your body. bone • Muscles attach to opposite sides of a ______ at a ____. When one muscle contracts and joint pulls the bone, the opposite muscle relaxes. Movement results in the direction of the pulling muscle Nervous system • Your nervous system includes: 1. 2. 3. 4. Brain ______________ Spinal cord ______________ Nerves ______________ Sense Organs ______________ The nervous system extends to all of the parts of the body. Parts of the Brain Brain stem - maintains blood pressure, • 1. ________ heartbeat, respiration, and digestion. Cerebellum • 2. __________ - controls balance and posture; helps fine tune movements Cerebrum • 3. __________ - Interprets information that senses gather; controls muscle movement, thinking, and language. Messages / Responses brain • The _______ interprets a message from one of your senses. responds by sending ____________ Nerve impulses • The brain ________ back through the ____________ to the Spinal cord muscles _________ for movement or action. Nerve cells • Nerve cells are called ________. neurons • __________ pass messages throughout your Neurons body. • Each neuron has a _________ with many Cell body branches. Dendrites • ____________ are short branches that carry messages from other neurons to the cell body. Axons • ___________ are long branches which carry messages away from the cell body to other neurons. A neuron has many dendrites but only one axon. Impulses Impulse • _________ - a message that travels along a neuron and from one neuron to the next. one • Impulses can travel in only _____ direction – from the _______ of one neuron to the axon dendrite __________ of another neuron. • Impulses travel along neurons to the _____. brain • Impulses → brain → sends messages to act → pass through the __________. Spinal cord Reflexes Reflex • __________ is a response that happens automatically. • Example: When you touch your hand to a hot stove and pull your hand away. You do not have to “think” about pulling your hand away – you just do it! Endocrine System • The nervous system helps to maintain balance in the body’s processes by interpreting information and telling the parts of the body to act. • The __________ system also helps to balance Endocrine the body’s processes such as growth and maintaining sugar levels. • The endocrine system is made up of glands ________. Glands • _____ gland - an organ that produces a chemical • _______________ - an organ that releases Endocrine gland chemical substances directly into the blood. • ___________ - the substances that the hormones endocrine glands release into the blood – hormones control many of your body’s functions. • The endocrine system releases _______ hormones when your body needs them. Endocrine Glands • Maintains internal balance by releasing hormones to _________ throughout the body. Target cells Target cells - each kind of hormone travels in • ________ the blood to a particular area in the body to perform certain tasks. • ______________ - a circular pathway that Biofeedback loop sends information back and forth from one part of the body to another. Endocrine Glands Gland Function Pituitary Controls development and body growth Thyroid Controls how cells release energy Parathyroid Controls the amount of calcium and phosphorus in the blood Adrenals Controls the body’s reaction to anger, fright, or fear Pancreas Controls the amount of glucose in the blood Ovaries Control female charactersitcs testes Control Male characteristics Transport Systems of the Body • The transport systems of the body include: – ______________ Digestive System - takes in materials needed by the body and breaks them down into a useable forms Circulatory System - carry blood and nutrients to – ______________ cells in all parts of the body Respiratory System - takes in oxygen that cells – _______________ need and gets rid of carbon dioxide wastes that cells produce. Digestive System • Organs of the _________ system work digestive together to break down food into a useable form. These organs include: – _____which helps to digest fat. Liver produces _____ bile The liver also stores some nutrients and breaks down harmful substances in the blood. – _______________ - bile is stored until it is Gallbladder released to the ______________. Small intestine – ___________ - produces _________ that flow into Pancreas enzymes the small intestine. Process of Digestion • ________ - help break down food into Enzymes nutrients • 1. _______ - mechanical digestion begins. Mouth Chemical ______ begins the process of _______ Saliva digestion. • 2. _________ - tongue pushes the softened Esophagus moistened food towards the esophagus. The smooth muscles of the esophagus push the food down to the stomach. Process of Digestion Continued • 3. _______ Stomach - continues mechanical digestion by squeezing the contents with muscle contractions. ______ Glands in the stomach produce ______ that breakdown enzymes and _______ acids __________. proteins • 4. ____________ - most digestion takes place Small Intestine here. – ____Villi tiny finger-like structures line the small intestine which increases the surface area for nutrient absorption into the blood stream. Process of Digestion Continued Large Intestine • 5. ____________ - materials that cannot be absorbed into the bloodstream pass into the large intestine. Very little digestion ______ takes place here. Water is absorbed and solid wastes are formed and stored until the body is ready to excrete them. Circulatory System • ___ Villi in the small intestine contain ________that pick up nutrients and pass them Blood cells Blood stream into the __________. Circulatory system • ______________ transports nutrients to all the parts of the body. • The circulatory system is made up of: – 1. __________ Blood Heart – 2.___________ Blood Vessels – 3.____________ The circulatory system consists of THREE elements Functions of the Blood Blood • _________has several different parts, each part has a different function • The biggest part of the blood is made up of a plasma liquid called _________. • The cells in the body depend on the plasma to Digestive system to the cells carry food from the ____________ water • Cells get _________ from the plasma Plasma • _________moves other important chemicals and hormones around the body Blood Cells • There are three types of blood cells: – Red blood cells – White Blood Cells – Platelets food • Cells need oxygen to get energy from _______. Red Blood Cells are bright red when they are • ___________ carrying _________. oxygen • After the cells give the oxygen to the cells that dark need it, their color changes to ________ red. Parts of the Blood • _______________ White blood cells protect the body against germs and harmful things • The number of white blood cells is always changing – the body will make more white blood cells when it needs to fight ________ infection. platelets • _____________ are pieces of cells that float in the blood platelets • _____________help to stop bleeding by clotting plasma • ___________ makes up more than half of the blood Blood cells • Red ______________ make up a little less than half of the blood White Blood Cells and ______________ platelets • ________________ make up a very small portion of the blood. Types of Blood Cells Red Blood Cells White Blood Cells Platelets Form Shaped like discs with a dimple on each side Different shapes and sizes that change as they work Not complete cells Function Carry oxygen to the rest of the body Protect your body from germs and other harmful things Form blood clots Disorder Sickle-cell anemia – blood cells are shaped like a crescent moon. They do not carry oxygen as well as they should. Leukemia is a type of cancer where the person’s white blood cells do not form correctly and their numbers increase too quickly An embolism is a clot that floats freely in the blood and can block a vessel Arteries, Capillaries, and Veins • __________can be thought of as highways Blood Vessels that your blood uses to move through your body. • Three kinds of blood vessels: – ____________ arteries – ____________ capillaries – _____________ Veins Each different blood vessel has a different Structure ___________ that helps it do its job. Arteries Arteries • __________ are blood vessels that carry blood away from the heart to other parts of the body • Arteries have ________, muscular walls that thick stretch when the heart pumps blood to it. • Arteries branch into smaller and smaller tubes until they branch into the smallest blood vessel in the body, the ________. capillaries Capillaries cell • The walls of the capillaries are only one _____ thick. red blood cells • The tubes are so narrow that ____________ must travel in a single file line through them Gases can easily pass through these thin walls • _____ oxygen moves from the blood into the capillaries • ______ to the cells Carbon dioxide • _____________ and other wastes go in the opposite direction from oxygen through the capillaries Veins • Capillaries join together to form _________ veins • _____ veins carry blood from cells back to the heart • The tiny veins formed by the capillaries join many times to form larger ____ veins. • Veins have _____-flaps that act like doors to keep valves blood flowing in one direction. • Arteries and capillaries do not have ________ valves • The pumping of the heart keeps blood flowing in the right direction through the capillaries and arteries. COOL FACT The network of blood vessels in the average adult human measures over 60,000 miles! If unraveled, it could wrap around the Earth’s equator over two times! Arteries & Veins • The largest ARTERY in the body is the AORTA, which carries blood away from the heart to the rest of the body (except for the lungs). • The two largest VEINS in the body are the superior and inferior VENA CAVA, which carry blood toward the heart from the rest of the body (except for the lungs). The Heart The word “cardio” is Greek for “HEART” The human heart (as with other mammals and birds) consists of 4 chambers Chambers of the Heart There are two ATRIA, or upper chambers. There are two VENTRICLES, or lower chambers. Respiratory System oxygen All cells in your body need ______. energy Cells use oxygen to release ________ from nutrients Carbon Dioxide gas as a waste. Cells produce _____________ Blood Carbon Dioxide _____delivers _______ and removes _________ oxygen from the body. Nose → trachea → lungs → bronchial tubes → bronchioles → alveoli Alveoli alveoili • _________ - air sacs at the end of the bronchioles. ______enters the blood and Oxygen Carbon Dioxide gas is removed in the alveoli. _____________ • _________ cover the alveoli. Capillaries Immune System • ___________ are organisms such as bacteria, pathogens viruses, and fungi that can cause diseases. • _____________ helps your body defend itself Immune System against _________. pathogens • How your body defends itself: – – – – ______ - protective barrier skin ______ tears - wash away bacteria _______ mucus - nose, mouth and throat trap pathogens saliva _________, ___________ Gastric juices in the stomach, and reflexes such as sneezing and coughing _______ When a Pathogen Enters the Body • ____________ White Blood Cell recognizes the pathogen and reproduces itself many times to fight against it. • Some white blood cells alert other white blood cells to produce ________ antibodies - chemicals that kill specific pathogens. • Other white blood cells attack body cells that contain the pathogens ________ - they kill the infected cell and the pathogens. Human Body System Working together Systems working together Respiratory and Circulatory Work harder through activity. Breathing rate increases which provides more oxygen to working muscles. Heart pumps faster and delivers more oxygen and nutrients to muscles while getting rid of carbon dioxide. Endocrine Hormones make sure the body has enough energy and stability Digestive Nutrients are in the blood ready to supply the body with energy Nervous Nerves gather information which is sent to the brain through the spinal cord. The brain interprets the messages and directs the parts of the body to respond Muscular and skeletal Muscles receive messages from the brain telling them to contract. As the muscles contract, the muscles pull on the bone which results in movement.