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(open or closed), system in which blood is not always contained within a network of blood vessels


(open or closed), system in which blood is contained within a network of blood vessels


specialized cells involved in sexual reproduction


strong connective tissue that supports the body and is softer and more flexible than bone


an animal whose body temperature varies with the temperature of its surroundings


An animal whose body controls and regulates its temperature by controlling the internal heat it produces


either of the two organs in the chest with which people and some animals breathe


Large, flat muscle at the bottom of the chest cavity that helps with breathing


a part of an organism consisting of an aggregate of cells having a similar structure and function


group of tissues that work together to perform closely realated functions

organ system

group of organs that work together to perform a specific function


process by which organisms maintain a relatively stable internal environment

large intestine

the last section of the digestive system, where water is absorbed from food and the remaining material is eliminated from the body


the opening through which food is taken in and vocalizations emerge


tube in wich food travels from mouth to the stomach


large muscular sac that continues the mechanical and chemical digestion of food

small intestine

organ that completes the chemical digestion of food and absorbs the nutrients


an enzyme that begins the process of breaking down a starch into a simple sugar

inflammatory response

nonspecific defense reaction to tissue damage caused by injury or infection


protein that helps destroy pathogens


substance that triggers an immune response


the outer layer of the skin covering the exterior body surface of vertebrates


the deep vascular inner layer of the skin


Subcutaneous layer, attaches dermis to underlying tissue, adipose, areolar connective tissues (energy reserve and padding), vascular

circulatory system

the organs and tissues involved in circulating blood and lymph through the body


tiny, thin-walled blood vessels that allow the exchange of gases and nutrients between the blood and the cells of the body


blood vessels that carry blood away from the heart


throat; passageway for food to the esophagus and air to the larynx

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