ORGANS & ORGAN SYSTEMS Recall that organisms are highly organized from atoms to to tissues to and organ systems. Cells differentiate and group together to create tissues to perform specific tasks. Similar tissues work together as to perform specific tasks to keep organisms functioning. The term organ means. Each organ performs specific functions and is made up of several types of and therefore several types of cells. For example, the heart contains muscle tissue that contracts to pump blood, fibrous (connective) tissue that makes up the heart valves and special cells that maintain the rate and rhythm of heartbeats. Organ systems are collections of organs that perform a major function for the organism. The healthy functioning of organ systems, organs, and tissues depends on the health of the cells in the tissues. Cells that receive the materials they need through the organ systems sustain the organism. ANIMAL ORGAN SYSTEMS There are organ systems that function within animals, although some animals lack one or more of them. These organ systems although have their own specific function, are interrelated and work together to meet the needs of the organism. 1
B10 Plant and Animal Organs & Organ Systems 2
B10 Plant and Animal Organs & Organ Systems 1. THE DIGESTIVE SYSTEM Extending from the mouth to the anus, this system has 4 steps: ingestion,,, and excretion. It breaks food into tiny molecules (nutrients) and absorbs them into the bloodstream. It also plays a vital role in eliminating solid wastes into the environment. This system includes the, small and large, rectum, and other associated organs like the pancreas, liver, and gallbladder, which produce digestive enzymes, remove toxins and store substances necessary for digestion. 2. THE CIRCULATORY SYSTEM Likely the most important system in animals, the circulatory system is an important system within an organism. It consists of the and major blood vessels (, and ). It transports blood around the body, which is the medium that carries oxygen necessary for respiration, carbon dioxide, nutrients, waste products, immune components, and hormones. 3. THE RESPIRATORY SYSTEM Responsible for breathing, the respiratory system has the, trachea, and other air tubes (bronchi). These organs aid in the exchange of oxygen and carbon dioxide, necessary components of cellular respiration. This system also has a vital role in maintaining the ph of the blood. 3
B10 Plant and Animal Organs & Organ Systems 4 & 5. THE MUSCULO SKELETAL SYSTEM These two systems work together to achieve and. Comprised of 3 types of muscle, as well as bones, tendons and ligaments, this tandem system also supports and protects the body. 6. THE NERVOUS SYSTEM This system consists of the, spinal cord, nerves and other sensory organs that coordinate and control actions of internal organs and body systems by sending and receiving in response to stimuli. Memory, learning, and conscious thought are all part of the nervous system, as well as maintaining autonomic functions such as our heartbeat, breathing, and the control of involuntary muscle actions. 7. THE INTEGUMENTARY SYSTEM The integumentary system is the outermost protective layer, which comes in the form of, hair, nails, scales, feathers and sweat glands depending on the organism. It prevents water loss and the invasion of foreign particles into the body. 8. THE LYMPHATIC (IMMUNE) SYSTEM This system is comprised of lymphatic vessels which are vital in the transport of extracellular fluid and fat to the circulatory system., thymus, tonsils and the spleen are all organs with roles in this organ system. 9. THE EXCRETORY (URINARY) SYSTEM The urinary system is comprised of the, bladder and ureters which remove metabolic wastes from the bloodstream. The kidneys filter blood and take out waste which is temporarily stored in the until it is ready to be excreted. 4
10. THE ENDOCRINE SYSTEM The endocrine system works with the nervous system to control the activity of internal organs as well as coordinating long range response to external stimuli. Comprised of the pituitary, adrenal, thyroid and other glands, this system secretes hormones that regulate metabolism, growth, and reproduction. These organs are not in contact with each other, although they communicate by chemical messages via the circulatory system. 11. THE REPRODUCTIVE SYSTEM The reproductive system carries out reproduction and control hormones that aid in sexua development. The major organ in male organisms is the testes, while in females it is ovaries. Both of these organs work closely with associated reproductive structures. PLANT ORGANS Plants have 4 major organs: roots, stems, leaves, and flowers. These organs make up th two major organ systems found in plants, the root system and the shoot system. 5
THE LEAF The leaf is an organ specialized for photosynthesis. Due to this process, leaves are typically flat (laminar) and very, exposing the pallisade cells (which have lots of ) to sunlight (which maximizes their ), allowing light to penetrate fully into the tissues. Leaves are also the sites in most plants where transpiration takes place and can also act as a storage for food and water. THE STEM The stem, usually found above the soil has three main functions: it provides support (to hold its flowers and fruits), transports fluids in (water and minerals) and (sugars) tissue between the leaves and roots, and stores nutrients. THE ROOT THE FLOWER Flowers are responsible for plant, through pollination or fertilization. Some flowers use sexual reproduction while others use asexual. In vascular plants, the root of a plant body typically lies below the surface of the soil. Roots are primarily responsible for the absorption of and inorganic nutrients via the root hairs and they are also responsible for anchoring the plant body in the soil. Roots often function in storage of sugar and nutrients as well. 6
PLANT SYSTEMS THE ROOT SYSTEM The root system includes parts of the plant that are below the ground, such as the roots, tubers, and rhizomes. Its functions include anchoring the plant in the soil, absorbing water and nutrients, conducting water and nutrients via the xylem and phloem, and food storage. THE SHOOT SYSTEM The shoot system is above the ground and includes the leaves, stems, flowers (if any), and fruits (if any). This system has a variety of functions, as it is vital in photosynthesis in the leaves, reproduction & dispersal with flowers, and transportation of water and nutrients via the xylem and phloem. 7
HOMEWORK 1. Describe how an organism is broken down into smaller components. Use an example. 2. Describe the chain of events that would occur in an organism if there was a malfunction in either the circulatory or nervous system. 3. Fill in the following table: Major Organs Primary Function Respiratory System Digestive System Skeletal System Nervous System Circulatory System 4. Describe the importance of size as it relates to plant organs. What structures do plants have that allow them to carry out their life functions? 5. List 3 different functions for each plant organ (excluding flowers). 8