Histology Lab 3 Scott.lehbauer@lethbridgecollege.ab.ca Muscle Tissues Muscle Tissue Facts • Well vascularized • Highly cellular tissues • Responsible for most types of body movement • Posses myofilaments which cause movement or contraction in all cell types Skeletal Muscle Structure – • Elongated cells • Cells are multi-nucleated • Nuclei are located on the periphery • Obvious striations throughout. Nuclei Skeletal Muscle Skeletal Muscle Location – • Attached to the skeleton • Occasionally attached to the skin Skeletal Muscle Skeletal Muscle Function – • Voluntary movement • Warm blood as the muscles produce heat. • Locomotion • Facial Expression Skeletal Muscle Smooth Muscle Structure – • Elliptically shaped cells with a centrally located nucleus • There are no striations present. • Cells are close together to form sheets. Smooth Muscle Location – • Digestive tract • Walls of the Uterus • Blood vessel walls Smooth Muscle Function – • Involuntarily controlled • Produces involuntary contractions through the linings of the digestive tract and ureters. This movement is called peristalsis. • Produces involuntary contraction and expansion of the blood vessels (vasodilation / vasoconstriction) Cardiac Muscle Structure – • Centrally located nucleus • Striated • Has branching of muscle cells with intercalated discs • Involuntary control, control is actually inherent so no external stimuli is required to cause contraction Cardiac Muscle Location – • In the heart Intercalated Disc Cardiac Muscle Function – • To contract continuously from inherent impulse. • Involuntary contraction. Nervous Tissue Nervous Tissue Facts • main component of the nervous system. • Contains 2 major cells types: 1. Neurons – are highly specialized nerve cells that generate and conduct nerve impulses. 2. Neuroglia – are supporting cells that are nonconducting that insulate and protect the neurons. Nervous Tissue Structure – • Neurons are branching cells. • Cell processes may be quite long. • Motor neurons have many dendrites but one axon. • Motor neurons are myelinated. • Cell body is called a cyton. • Supporting connective tissue is called Neuroglia Cyton Neuroglial Cells Nervous Tissue Location – • Brain • Spinal Cord • Peripheral Nerves Nervous Tissue Function – • coordinates activities between the brain, spinal cord and body organs. Cell Nucleus Nucleus of Neuroglial Cell X – Section of Spinal Nerve Epineurium – surrounds several groups of neurons. Perineurium – surrounds a group of neurons. Perineurium Epineurium X – Section of Spinal Nerve Endoneurium – is the covering around one neuron. Axon – is the central grey spot. Myelin – is the white surrounding the axon. Endoneurium Axon X – Section of Spinal Cord Central Canal Meninges White Matter Grey Matter 1.) a.) Name the tissue type below. b.) What type of cell is labeled B? B 2.) a.) Where in the body would you find this tissue type? b.) What protein accumulates in the cells as you approach the apical surface of this tissue? 3.) a.) Name the cell type labeled A. b.) Name the structure labeled B. A B 4.) a.) Name one function of this tissue type. b.) Name one place in the body you would find this tissue. 5.) a.) Name the fiber type labeled A. b.) Name this tissue type. A 6.) a.) What is the function of mast cells? b.) What is the function of fibroblasts? 7.) a.) Name this tissue type. b.) What is the function of the cell labeled B? B 8.)a.) Where in the body would you find this tissue type? b.) What protein is the fiber labeled B made from? 9.) a.) Name this tissue type. b.) Name the structure labeled B. B 10.) a.) Name this tissue type. b.) Name one function of this tissue type. EXAM NOTES 1. Exam runs on November 13th from 4-7pm. 2. It is in IB1101. 3. It will be a power point exam similar to the practice tests. 4. You will have 1 minute per slide and 2 questions per slide. 5. The exam should take 21 minutes to write.