A and P Midterm Review Types of Tissue • 1. Epithelial tissue: covers and protects the body surface, lines body cavities, specializes in moving substance into and out of blood (secretion, excretion, and absorption), and forms many glands. • 2. Connective tissue: Supports body and its parts to hold and connect it together, transport substances and protect it from foreign invaders. • 3. Muscle Tissue: produces movement; it moves the body and its parts. Cells are specialized for contractility and produce movement by shortening fibers. • 4. Nervous Tissue: Most complex. Communication between parts and integration of activities. Major function is the generation of complex messages form coordination of body function. Epithelial Tissue • Membranes (covering and lining) • Functions: ▫ 1. Protection – Skin- tough impermeable epithelial covering ▫ 2. Sensory- In the eye, skin, nose, and ear . ▫ 3. Secretion- glandular 4. Absorption- gut (nutrients) and respiratory tract (oxygen and CO2 exchange) ▫ 5. Excretion- Kidney tubules, concentrates urine Characteristics of Connective Tissue Made predominantly of matrix of intercellular material with few cells ie. The matrix of blood is plasma Fibers maybe: Collagenous- white tough and strong (ligaments) Reticular- delicate- surrounding organs Elastic- vocal cords Muscle Tissue • Skeletal- Muscle to bone attachment. Voluntary. Tissue is striated • Smooth –Muscle in organs(visceral tissue), involuntary, non striated • Cardiac- Wall of heart. Striated but involuntary. Characteristic is intercalated disc. Nervous Tissue • Brain, Spinal cord and nerves • Basic cell= Nerve cells (NEURONS) and neuroglia, which are supporting cells. Cell Organelles • • • • • • • Nucleus- plans for proteins, contains DNA Mitochondria- powerhouse of cell Lysosomes- recycle material Golgi- pack sorts and delivers proteins, Cytoplasma- cushions provides nutrients Membrane-maintains homeostasis Vacuole- temporary storage Skin Layers of the epidermis Cell Layers of Epidermis 1. Stratum Corneum (top layer) Dead cells filled with keratin (barrier area) 2. Stratum Lucidum (clear layer) cells filled with keratin precursor called eleidin absent in thin skin. 3. Stratum granulosum (granular layer) cells arranged 2-3 layers and filled with keratohyalin granules that contain a high # of lysosomes ( to digest the cytoplasm as it is replaced with keratin Cell layers- epidermis continued 4. Stratum Spinosum (spiny layer) cells arranged in 8-10 layers with prominent desmosomes (strong connections between cells appear spiny in microscope): Rich in RNA which is necessary for the protein synthesis of Keratin. 5. Stratum basale (base layer) single layer of columnar cells: only these cells undergo mitosis and then migrate through the other layers until they are shed. • 4.The pigment that gives you skin color is called what? • 5. What is the purpose of the skeletal system? Muscular system? Nervous system? Bone Structure • • Bone tissue is a type of connective tissue, so it must consist of cells plus a significant amount of extracellular matrix. Bone cells: 1. Osteoblasts Bone-building cells. Synthesize and secrete collagen fibers and other organic components of bone matrix. Initiate the process of calcification. Found in both the periosteum and the endosteum The blue arrows indicate the osteoblasts. The yellow arrows indicate the bone matrix they’ve Bone Structure 2. Osteocytes Mature bone cells. Osteoblasts that have become trapped by the secretion of matrix. No longer secrete matrix. Responsible for maintaining the bone tissue. Yellow arrows indicate osteocytes – notice how they are surrounded by the pinkish bone matrix. Blue arrow shows an osteoblast in the process of becoming an osteocyte. On the right, notice how the osteocyte is “trapped” within the pink matrix 3. ▫ ▫ ▫ ▫ ▫ Osteoclasts Huge cells derived from the fusion of as many as 50 monocytes (a type of white blood cell). Cells that digest bone matrix – this process is called bone resorption and is part of normal bone growth, development, maintenance, and repair. Concentrated in the endosteum. On the side of the cell that faces the bone surface, the PM is deeply folded into a ruffled border. Here, the osteoclast secretes digestive enzymes (how might this occur?) to digest the bone matrix. It also pumps out hydrogen ions (how might this occur?) to create an acid environment that eats away at the matrix. What advantage might a ruffled border confer? Why do we want a cell that eats away at bone? (Hint: bone is a very dynamic tissue.) Microscopic Structure of Compact Bone • Consists of multiple cylindrical structural units known as osteons or haversian systems. • Imagine these osteons as weightbearing pillars that are arranged parallel to one another along the long axis of a compact bone. The diagram below represents a long bone shaft in cross-section. Each yellow circle represents an osteon. The blue represents additional matrix filling in the space btwn osteons. The white in the middle is the marrow cavity. Osteons • Each osteon consists of a single central canal, known as a haversian canal, surrounded by concentric layers of calcified bone matrix. ▫ Haversian canals allow the passage of blood vessels, lymphatic vessels, and nerve fibers. ▫ Each of the concentric matrix “tubes” that surrounds a haversian canal is known as a lamella. ▫ All the collagen fibers in a particular lamella run in a single direction, while collagen fibers in adjacent lamellae will run in the opposite direction. This allows bone to better withstand twisting forces. Running perpendicular to the haversian canals are Volkmann’s canals. They connect the blood and nerve supply in the periosteum to those in the haversian canals and the medullary cavity. Bone Classification • 4 types of bones: 1. Long Bones 2. Much longer than they are wide. All bones of the limbs except for the patella (kneecap), and the bones of the wrist and ankle. Consists of a shaft plus 2 expanded ends. Your finger bones are long bones even though they’re very short – how can this be? Short Bones Roughly cube shaped. Bones of the wrist and the ankle. Carpal Bones Femur Bone Classification • Types of bones: 3. Flat Bones Thin, flattened, and usually a bit curved. Scapulae, sternum, (shoulder blades), ribs and most bones of the skull. Sternum 4. Irregular Bones Have weird shapes that fit none of the 3 previous classes. Vertebrae, hip bones, 2 skull bones ( sphenoid and the ethmoid bones). Sphenoi d Bone Long Bone • Labeling The Motor Unit= Neuromuscular junctions (nerve meets muscle) Figure 35-15 The Ear Section 35-4 Oval window Anvil Stirrup Semicircular canals Hammer Cochlear nerve Cochlea Bone Auditory canal Tympanum Round window Eustachian tube Somatotype- a particular category of body build and physique • Endomorph- Heavy rounded physique characterized by large accumulations of fat in the trunk and thighs. • Mesomorph-Muscular physique • Ectomorph- thin fragile physique characterized by little body fat accumulation. Examples Knee Tendon • ATP and Muscle Contraction ppt 3 Major Parts of the brain and their function • Cerebrum- conscious awareness • Cerebellum- balance, posture and coordination of movement. • Brainstem- Regulates involuntary activities like temp, heart rate, breathing 4 lobes of the brain and their function • Frontal lobe- intellectual power • Temporal Lobe- Primarily hearing and speech • Occipital Lobe- receive and interprets visual information • Parietal lobe- Sensory reception and processing JOINTS: Where 2 bones meet. • Facilitate the movement of bones in relation to one another. Attachment of Muscles • 1. Origin- point of attachment that does not move when the muscle contracts. • 2. Insertion- point of attachment that moves when the muscle contracts Movement • • • • • • • Abduct Adduct Flex Extend Lateral flexion Rotation Circumduction Sarcomere • Segment of myofibril between two successive Z lines • Each myofibril consists of many sarcomeres • Contractile unit of the muscle fiber Labeling • Body Directional Terms on Final ▫ ▫ ▫ ▫ ▫ ▫ ▫ ▫ ▫ Brachial Carpal Femoral Posterior Axillary Cervical Orbital Patellar Buccal Lumbar Anterior Cranial Caudal Neuron • Label: node of Ranvier, axon, dendrite, synaptic junction, myelin Motor Unit Anatomy of the brain Motor area Cerebrum Sensory area Speech area Language area Vision area Taste area Intellect, learning, and personality General interpretation area Hearing area Balance area Brain stem Cerebellum Sarcomere Human Skeletal Bones WE ARE DONE!!! Half way through your senior year!! It only gets faster from here.