Human Body 7th Grade

Think! Students in a seventh grade class were arguing about which organ system is the most important. Some said the circulatory system because it carries blood around the body. Others said the respiratory system because you need oxygen to live. Another said the excretory system because otherwise our bodies would be full of waste. What do you think?

Work with your group to sort the cards and complete the worksheet

Body Organization Cells are the smallest part that can be said to be alive. Cells come together to form tissues. Tissues come together to form organs. Organs come together to form organ systems. And organ systems come together to form an organism.

Cells in a multicellular organism are differentiated Cells in a multicellular organism are differentiated. That means they have different jobs that they fulfill for the body. Because of their different jobs they often look very different from each other.

Redesign the Body Project http://mariana68.wixsite.com/bl-humanbodyredesign Redesign the Body Project With your group make a list of things you need to know before you begin your project in order to do a good job. Keep this list in the center of your table throughout so that you can refer to it as you research

Redesign the Body (continued) You need 18 XP to begin your redesign To gain XP: Visit sites about these 8 body systems (skeletal, muscular, nervous, respiratory, digestive, excretory, circulatory, immune). Write down the basic functions of each system, important organs, how it works with other systems (this is worth 2 points each) Complete the Body System problems sheet for at least two body systems (4 points each)

Redesign the Body (continued) Your project should include: An explanation of the problem you are trying to solve Why you believe this problem is important to fix An eye-catching presentation (pretend you are competing with the other groups to get the funding of an important government organization for your project) How your design will fix the problem Address any possible challenges to your project Be ready to answer questions

Circulatory system Main organs; Heart – muscle that pumps blood throughout the body Lungs – takes in oxygen for the body; expels carbon dioxide Arteries, Veins – carries blood around the body

Is deoxygenated blood really blue? The main function of the circulatory system is to carry oxygen, glucose, and other needed nutrients throughout the body Think of it as a highway Just like a highway it is separated to keep traffic flowing smoothly (much like the two sides of the highway keep traffic flowing) Arteries carry blood away from the heart; veins carry blood towards the heart Is deoxygenated blood really blue?

Why is the circulatory system important? The circulatory system carries blood throughout the body Without the circulatory system cells would not be able to get the oxygen and nutrients they need so cellular respiration could not take place

Excretory system Major organs: Kidneys Large intestine Liver Skin lungs

Why is the skin part of the excretory system? The main function of the excretory system is to get rid of waste inside the body A subsystem within the excretory system is the urinary system which contains the kidneys, ureters, bladder, and urethra. The main function of this subsystem is to filter waste from your blood.

Why is it important Without the function of the excretory system waste would back up in your body. This would cause your other organs to malfunction and even fail. Fun fact: a person can live with only one kidney. However, in order to protect their kidney it is suggested that they avoid contact sports and even watch their diet to be sure their one working kidney continues to function properly

Digestive system Main organs: Salivary glands Pharynx Esophagus Stomach Small intestine Large intestine rectum Accessory digestive organs: Liver Gallbladder pancreas

The main function of the digestive system is to break down food and absorb nutrients that the body needs to survive. Enzymes in your saliva and stomach acid break down the food. The small intestine is the chief organ involved in absorbing nutrients. The accessory organs secrete bile and other enzymes into the small intestine to help in digestion.

Why it’s important Without the digestive system your body would not be able to obtain the nutrients it needs to survive. Your body would not be able to get glucose and therefore there would be no energy because there would be no cellular respiration

Respiratory system Main Organs: Nose Pharynx Larynx Trachea Bronchi lungs

The Respiratory system The human respiratory system is a series of organs responsible for taking in oxygen and expelling carbon dioxide. This is how it does its job. The primary organs of the respiratory system are lungs, which carry out this exchange of gases as we breathe. This is the main job of the respiratory system. Without this system your brain cells would start to die causing serious brain damage and sometimes could cause death. This is why you should take care of your respiratory system. This is also why you need your respiratory system.

Muscular system Skeletal Muscle: creates movement in the body; skeletal muscle is attached to bones and does this by pushing and pulling bones in different directions Cardiac muscle: causes the heart to beat Smooth muscle: involuntary muscle controlled by nerve impulses; found in the lining of hollow organs, respiratory passageways, and blood vessels

Why it is important The muscular system is responsible for movement within the body. Without the muscular system not only would you be unable to walk or move at all, but your organs could not continue bodily functions due to the lack of smooth muscle tissue. Your organs and body would die due to lack of nutrients and oxygen.

Endocrine system The endocrine system is made up of glands. A gland is an organ that secretes particular chemical substances (such as hormones). Hormones are chemical signals that help direct the body and maintain its functions Homeostasis is the ability of an organism to maintain stability in spite of changes. Hormones help your body maintain homeostasis. These hormones are responsible for the maintaining of body temperature, the ability of the organism to protect itself, weight gain and loss, sleeping habits, reproduction, and other things.

The major glands of the endocrine system are the: Hypothalamus Pituitary Thyroid Parathyroids Adrenals Pineal gland Reproductive organs pancreas

What would happen to a person on a cold day if their body could not perform homeostasis? Why it is important The Endocrine system is incredibly important. Without the endocrine system your body could not regulate itself in terms of nutrient intake (feeling hungry and thirsty), maintaining temperature, even sleeping habits.

Nervous system The main organs of the nervous system are: Brain Spinal cord Sensory organs (those responsible for your five senses) nerves

Congenital Insensitivity to Pain is a disease in which a person cannot feel pain. Is this a good thing? The nervous system is responsible for our bodies response to stimuli. That means that the reason we are able to respond to our environment is because of our nervous system. The brain sends signals called impulses through our nerves like electricity is transmitted through a wire. These impulses allow us to feel pain, move, and regulate ourselves. Without our nervous system we would not be able to respond to our environment

Cellular Respiration Essay (due 10/11) Explain how the body systems (circulatory, excretory, digestive, respiratory, muscular, endocrine, nervous) work together through the process of cellular respiration. Explain how matter and energy are cycled through the body during the process of cellular respiration.