Animal Body Systems: Organization

Animal Cells All animal cells have a nucleus, cell membrane, cytoplasm, ribosomes, and lack a cell wall, but are they all alike? Red & white blood cells Specialization of cells – designed for a specific function Think about it: How does their structure fit their function? Discuss how epithelial cells and flat and thin (skin!), while red blood cells contain a protein that binds easily with oxygen. Ask students to discuss how the shape of a neuron makes it well-suited for transmitting electrical impulses. Epithelial cell (skin) Neuron (brain)

Cells Tissues Similar cells are grouped together into units called tissues These cells work together to perform a particular function or task Cell types in the body are grouped into four basic kinds of tissue. 1. Epithelial 2. Nervous 3. Connective 4. Muscle Before discussing in any more detail, ask students to list some examples of each type of tissues to see what they know.

1. Epithelial Tissue Covers most internal and external body surfaces Protects other tissues from dehydration and physical damage Also produce secretions such as sweat and mucus Cells are flat and thin and usually only a few cells thick Ask students to come up with some examples (skin, lining of the digestive tract, surrounding organs). Back to Tissues

2. Nervous Tissue Transmits nerve impulses (information) throughout the body Consists of neurons (nerve cells) and their supporting cells Ask students what major organs are made of nerve tissue (brain, spinal cord, nerves). Back to Tissues

3. Connective Tissue Supports, protects, and insulates the body What structures in the body do you think are made of connective tissue? Fat Bone Cartilage Blood Ask the students to come up with the list of connective tissue examples before just pulling them up on the slide. Back to Tissues

4. Muscle Tissue Cells that are able to contract in response to stimulation They make you move!  Three types: Skeletal muscle- called voluntary muscle because you can controlcontractions Smooth muscle- called involuntary muscle because you cannot consciously control its slow, long-lasting contractions Cardiac muscle- found in the heart Back to Tissues

Tissues Organs A group of different types of tissues that work together to perform a single function EXAMPLE: The heart contains cardiac muscle tissue and connective tissue, is surrounded by epithelial tissues, and is stimulated by nervous tissue. As different as each of these tissues are, they all work together to make your heart work!

Organs Systems An organ system is a group of organs that works together to carry out major activities or processes of the body Each organ belongs to at least one organ system (but may belong to several!) EXAMPLE: the stomach is just one organ in the digestive system – it works with many other organs (the mouth, intestines, and more) to make the process of digestion possible. What organ systems make up a human? (hint, there are 11!) Ask the last question and get the students to come up with (hopefully!) all of the following: digestive, endocrine, reproductive, respiratory, circulatory, muscular, skeletal, integumentary, immune, excretory, nervous

11 Human Body Systems Respiratory Skeletal Circulatory Integumentary Endocrine Excretory Nervous Muscular Skeletal Integumentary Reproductive Immune Digestive

Let’s Review… What are the 5 main levels of organization in animal systems? (from smallest to largest) Give 2 examples of each. - Cells - Tissues - Organs - Systems Where are organs stored and protected?

Closing Activity Grape A Grape B Initial Mass Description of Grape Mass after 24 hours Draw a data table in your notebook similar to the one above. Obtain two grapes and two small containers. Place each grape one of the small containers. Label them Grape A and Grape B. Measure the mass of each grape and record it in your data table in the appropriate column. Using forceps, peel the skin off of Grape A and place the grape back into its container. Discard the skin. Set the containers in the designated location for 24 hours.