Unit 6: The Human Body Lesson 1: Organization

Bell Work Why is it important to learn about the human body? What are 3 things that you would like to know about the human body?

SC Standards Standard 7.L.3: The student will demonstrate an understanding of how the levels of organization within organisms support the essential functions of life. 7.L.3B Conceptual Understanding: Multicellular organisms (including humans) are complex systems with specialized cells that perform specific functions. Organs and organ systems are composed of cells that function to serve the needs of cells which in turn serve the needs of the organism. 7.L.3B.1: Develop and use models to explain how the structural organizations within multicellular organisms’ function to serve the needs of the organism. S.1A.2: Develop and use models to (1) understand or represent phenomena, processes, and relationships, (2) test devices or solutions, or (3) communicate ideas to others. 7.L.3B.2: Construct explanations for how systems in the human body (including circulatory, respiratory, digestive, excretory, nervous, and musculoskeletal systems) work together to support the essential life functions of the body. S.1A.6: Construct explanations of phenomena using (1) primary or secondary scientific evidence and models, (2) conclusions from scientific investigations, (3) predictions based on observations and measurements, or (4) data communicated in graphs, tables, or diagrams

Learning Objectives It is essential that students develop and use models to explain how the structural organizations within multicellular organisms’ function to serve the needs of the organism. It is essential for the student to be able to relate organization within an organism. The levels of organization, from the simplest level to the most complex are: It is essential that students construct explanations for how systems in the human body (including circulatory, respiratory, digestive, excretory, nervous, and musculoskeletal systems) work together to support the essential life functions of the body. It is essential for the student to be able to understand the basic form and function of each of the following body systems as well as the interrelationships that occur between systems to ensure the survival of the organism.

Level of Organization The levels of organization: Cells, tissue, organs, organ systems, and organisms Cell: the basic unit structure and function in a living organisms Human body has over 100 trillion cells

Review of Cell Parts

Function of Cells Keeps organisms alive Digest food and release energy Grow and reproduce Get rid of waste

Tissues Tissues are made of similar cells and perform the same functions. 4 types of tissue Muscle Nervous Connective Epithelial

Tissue Types Muscle Tissue: Can contract and shorten causing movement Nervous Tissues: directs and controls the process of movement Connective Tissue: support for your body, Connects parts of the body Epithelial Tissue: covers the surface of your body Protects delicate structures

Organs, Systems, and Organisms Made of one or more types of tissues Performs a specific job Systems 10 Body systems Body systems contain multiple organs and tissues Organisms Are complex Made of multiple organ systems

Human Organ Systems

Movement Movement happens because of interaction between body systems Muscles and bones work together, making your body move Nervous systems tells your muscles when to act

Muscle and Bones and Joints Skeletal muscles are attached to the skeleton Provide the force to move the bones Joints in the body can bend in many ways The skeleton bends at joints Joint are a place in the body where two or more bones come together.

Transporting Materials Circulatory, Respiratory, Digestive, and Excretory Systems play key roles in moving materials around the body. Circulatory system: includes heart, blood vessels and blood Blood flows through the veins and carries Water Oxygen Food Waste Carbon Dioxide

Breathing You breathe over 20,000 times a day Oxygen moves in when you inhale Carbon dioxide move out when you exhale

Getting Food Respiratory takes in oxygen Circulatory delivers oxygen to your cells Digestive system breaks down food into sugar and nutrients Nutrient is a substance that you get from food and your body needs to function. Nutrients move from the digestive system to blood. Circulatory system delivers the nutrients to the body.

Moving Waste out of the Body Excretory system eliminates waste from your body Respiratory and Circulatory are also involved in the excretory system Carbon Dioxide and other waste go through the blood stream Carried to the liver and kidneys which process urine.

Review Questions What are the levels of organizations (from smallest to largest)? What are the body systems? How many body systems are there?

Lesson 2: Interactions and Homeostasis Unit 6: Human Body Lesson 2: Interactions and Homeostasis

Bell Work Muscle and bones make up what system? What are the 4 types of tissue? Describe the function of the 4 types of tissue.

Control of Bodily Functions Chemical Signals are produced by the Endocrine system Glands produce and release chemical signals The Nervous and Endocrine Systems work together to control bodily functions.

Nervous System Eyes, ear, skin, nose, and taste buds send and receive information from the environment Signals from your nervous systems help you to react to stimulus (stimuli)

Thoughts Imagine you are playing softball on a warm summer day. Write down two ways that your body would adjust to keep you cool and to keep your muscles working.

What is Homeostasis? The process by which organisms maintain a relatively stable internal environment How does the human body maintain homeostasis? The eleven organ systems of the human body work together to maintain homeostasis. Homeostasis is the process by which organisms keep internal conditions relatively constant despite changes in external environments.

A Changing Environment The external environment around an organism is constantly changing. These changes threaten the stability of an organism’s internal environment. The maintenance of a relatively stable internal environment is called homeostasis.

Responses to Change Organisms must carry out many chemical reactions to grow, obtain energy, and reproduce. Many organisms also move, breathe, produce heat, and do other tasks. All of these activities require the organism to maintain a relatively stable internal environment.

Responses to Change Organisms detect and respond to both internal and external environments in a variety of ways. Detection and response can take place at both the cellular and organismal level. Failure to respond to change can result in an organism’s death.

Responses to Change Humans must also control internal water levels. About 2/3 of the human body is made of water. If a person loses too much water, by sweating or urination, dehydration will occur. Dehydration causes blood pressure to drop significantly until death occurs.

Humans and Homeostasis Humans are constantly subjected to environmental stresses that threaten to upset the delicate balance that exists within our cells and tissues. Humans require multiple systems for digestion, respiration, reproduction, circulation, movement, coordination, and immunity. These systems interact to maintain homeostasis.

Humans and Homeostasis The organs and systems of the human body help to provide all of the cells with their basic needs. Each cell needs a constant supply of nutrients and oxygen, removal of waste materials, and protection from disease. With the exception of the reproductive system, each of the human body systems performs a task that helps stabilize the body’s internal environment.

Humans and Homeostasis In the human body, the main components of homeostasis are the following: the concentration of salts The pH of the internal environment The concentration of nutrients and waste products The concentration of oxygen and carbon dioxide The volume and pressure of extracellular fluid

Example Humans and Homeostasis For example, the concentration of oxygen and carbon dioxide is controlled by four different body systems. First, the respiratory system brings oxygen into and carbon dioxide out of the body. The circulatory system distributes the oxygen to the body’s tissues and picks up carbon dioxide. If the level of carbon dioxide gets too high, the nervous system instructs the muscular system to make the muscles around the rib cage work harder. This action allows the lungs of the respiratory system to breathe faster, to get rid of excess carbon dioxide.

Review Questions What is the nervous system? What is the Endocrine system? What is homeostasis and why is it important?