organization of the human body

groups of tissues form organs

A single tissue alone cannot do all the jobs that are needed to keep you alive and healthy. Two or more tissues working together can do a lot more. An organ is a structure made of two or more tissues that work together. The heart ( Figure 1.2) is made up of the four types of tissues. The four different tissue types work to- gether in the heart as they do in the other organs.


organization of your body cells tissues organs

Cells are grouped together to carry out specific functions. A group of cells that work together form a tissue. Your body has four main types of tissues, as do the bodies of other animals. These tissues make up all structures and contents of your body. An example of each tissue type is pictured in the Figure 1.1. Your body has four main types of tissue: nervous tissue, epithelial tissue, connective tissue, and muscle tissue. They are found throughout your body. 1. Epithelial tissue is made up of layers of tightly packed cells that line the surfaces of the body. Examples of epithelial tissue include the skin, the lining of the mouth and nose, and the lining of the digestive system. 2. Connective tissue is made up of many different types of cells that are all involved in supporting and binding other tissues of the body. Examples include tendon, cartilage, and bone. Blood is also classified as a specialized connective tissue. 3. Muscle tissue is made up of bands of cells that contract and allow movement. 4. Nervous tissue is made up of nerve cells that sense stimuli and transmit signals. Nervous tissue is found in nerves, the spinal cord, and the brain.


organ systems work together

Your bodys 12 organ systems are shown below ( Table 1.1). Your organ systems do not work alone in your body. They must all be able to work together. For example, one of the most important functions of organ systems is to provide cells with oxygen and nutrients and to remove toxic waste products such as carbon dioxide. A number of organ systems, including the cardiovascular and respiratory systems, all work together to do this. Organ System Cardiovascular Major Tissues and Organs Heart; blood vessels; blood Lymphatic Lymph nodes; lymph vessels Digestive Esophagus; stomach; small intes- tine; large intestine Pituitary gland, hypothalamus; adrenal glands; ovaries; testes Endocrine Function Transports oxygen, hormones, and nutrients to the body cells. Moves wastes and carbon dioxide away from cells. Defend against infection and dis- ease, moves lymph between tissues and the blood stream. Digests foods and absorbs nutrients, minerals, vitamins, and water. Produces hormones that communi- cate between cells. Organ System Integumentary Major Tissues and Organs Skin, hair, nails Muscular Cardiac (heart) muscle; skeletal muscle; smooth muscle; tendons Brain, spinal cord; nerves Nervous Reproductive Respiratory Female: uterus; vagina; fallopian tubes; ovaries Male: penis; testes; seminal vesi- cles Trachea, larynx, pharynx, lungs Skeletal Bones, cartilage; ligaments Urinary Kidneys; urinary bladder Immune Bone marrow; spleen; white blood cells Function Provides protection from injury and water loss, physical defense against infection by microorganisms, and temperature control. Involved in movement and heat pro- duction. Collects, transfers, and processes information. Produces gametes (sex cells) and sex hormones. Brings air to sites where gas ex- change can occur between the blood and cells (around body) or blood and air (lungs). Supports and protects soft tissues of body; produces blood cells; stores minerals. Removes extra water, salts, and waste products from blood and body; controls pH; controls water and salt balance. Defends against diseases.

groups of organs form organ systems

Your heart pumps blood around your body. But how does your heart get blood to and from every cell in your body? Your heart is connected to blood vessels such as veins and arteries. Organs that work together form an organ system. Together, your heart, blood, and blood vessels form your cardiovascular system. What other organ systems can you think of?

instructional diagrams

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there are only four types of tissue in the human body.

-->  a. true

b. false

a group of similar cells that work together is known as a organ.

a. true

-->  b. false

which organ system provides protection from injury and water loss, and physical defense against infection by microorganisms?

a) the lymphatic system

b) the immune system

-->  c) the integumentary system

d) the urinary system

which organ system collects, transfers, and processes information?

-->  a) the nervous system

b) the endocrine system

c) the reproductive system

d) the lymphatic system

which organ system is composed of the trachea, larynx, pharynx, and lungs?

a) the digestive system

b) the urinary system

c) the endocrine system

-->  d) the respiratory system

which is associated with the reproductive system?

a) the seminal vesicles

b) the fallopian tubes and ovaries

c) the production of gametes and sex hormones

-->  d) all of the above are associated with the reproductive system.

which is associated with the endocrine system?

a) bone marrow

b) blood vessels

-->  c) hormones that communicate between cells

d) all of the above are associated with the endocrine system.

diagram questions

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