Lessons 8 and 9

function (job) What is the shape of a cell usually related to? You may or may not wish to distinguish between cytosol and cytoplasm. The correct use of each term is shown here. Most high school textbooks, however, use the word “cytoplasm” to mean “cytosol.”

cell the basic unit of structure and function of all living things

tissue a group of similar cells working together to perform a specific function

organ A group of tissues that work together to perform a function or task

four There are _____ basic types of tissue in animals: muscle tissue nervous tissue connective tissue epithelial tissue

the heart, brain, stomach, and lungs Examples of organs are: ________________ Organs usually perform a more complex task than a tissue.

organ system a group of organs that work together to perform a complex function

Examples of organ systems are: circulatory, nervous system, digestive system, respiratory system, and endocrine system

organism a living thing

cell-tissue-organ- organ system-organism smallest/first/least complex organ organism tissue organ system cell largest/last/most complex

organs Which are more complex, tissues or organs?

tissues Which are more complex, tissues or cells?

organ systems Which are more complex, organ systems or organs?

yes Can an organ belong to more than one organ system? For example, the heart is part of the circulatory and respiratory systems.

Can unicellular organisms have tissues, organs, or organ systems? No. Tissues are made of more than one cell.

cellular respiration the process in which oxygen is combined with glucose to release energy

respiratory system the body system that takes in oxygen and releases carbon dioxide

lungs elastic, sponge-like organs in the chest (the main organs of the respiratory system) Lung

alveoli tiny air sacs within the lungs where gases are exchanged between the lungs and the blood

alveoli tiny air sacs within the lungs where gases are exchanged between the lungs and the blood

capillaries the smallest blood vessels connect the arteries and veins they exchange gases and nutrients between the blood and body cell

oxygen alveoli ___________________ enters the blood through the thin walls of the ___________________

trachea the tube that transports air from the throat to the lungs also called the windpipe

bronchi a pair of tubes that branch off of the trachea and enter the lungs

diaphragm a sheet-like muscle just below the lungs that expands and contracts the chest cavity to control breathing

circulatory system the transport system that uses blood to carry nutrients, oxygen, etc. to the cells of the body and carries wastes away from the cells

heart a muscular organ that pumps blood throughout the body

atria/atrium the upper chambers of each side of the heart

ventricles the lower chambers of each side of the heart

arteries blood vessels that carry blood away from the heart (with oxygen) (shown in red)

veins blood vessels that carry blood toward the heart (without oxygen) (shown in blue)

valve structures found in the heart that keep the blood flowing forward

They open up to let the blood move ahead, then they close quickly to keep the blood from flowing backward. What do heart valves do?

Your blood relies on four special valves inside the heart. A valve lets something in and keeps it from going backward. These valves all work to keep the blood flowing forward. They open up to let the blood move ahead, then they close quickly to keep the blood from flowing backward.

What makes the sound of your heartbeat? This sound comes from the valves closing and shutting on the blood inside the heart. A healthy heart makes a lub-dub sound with each beat.

What does the right side of your heart do? The right side of your heart receives oxygen poor blood from the body (and pumps it to the lungs).

What does the left side of your heart do? The left side of the heart receives oxygen rich blood from the lungs and pumps it out to the body. Left comes from the Lungs

Explain how gas exchange takes place in the alveoli. Oxygen diffuses from alveoli to blood into capillaries. Carbon dioxide diffuses out from the blood in capillaries to alveoli.

Alveolus Body Cell Capillary

Explain how gas exchange takes place in cells. Oxygen diffuses out from the blood in the capillaries into cells. Carbon dioxide diffuses from cells to blood in capillaries.

plasma a yellowish fluid that is mostly water in which blood cells are suspended; it also contains dissolved nutrients, minerals, salts, and gases

red blood cells blood cells that carry oxygen to the cells of the body and carry carbon dioxide from cells back to the lungs

white blood cells the type of blood cells that help the body fight disease by attacking invading microorganisms and making antibodies to fight infection

platelets cell fragments that help form blood clots to stop bleeding

Blood is made up of about: 50% plasma 48% red blood cells 2% platelets and white blood cells