Introduction and Terminology

Transcription

1 Introduction and Terminology Histology - study of tissues (histo = tissues). Tissue Epithelial Tissue Covers and protects exposed surfaces. Muscle Tissue Skeletal muscle, smooth muscle and cardiac muscle. Skeletal muscle is usually attached to the skeleton and its contractions move or stabilise the position of the bone. Cardiac muscle is only found in the heart and its main function is to propel blood through the body. This is involuntary. Smooth muscle can be found in blood vessels, circulatory, digestive and reproductive system, its the muscle that does the job on its own, like cardiac muscle, it's involuntary - we don't have control over it. Connective Tissue Basically fills up space. It's made up of: blood, fat, loose (fat), dense (bones). Provides structural support and stores energy. Neural Tissue Carries and Sends information from the brain to the rest of our body. Works by Neurons, by conducting electrical impulses. Anatomical Planes Coronal - front and back (cuts the ears) Transverse - top and bottom (cuts mid-section) Sagittal - left and right (cuts the nose)

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3 Bones Function 1. Support - it holds up our body and our limbs. 2. Protection - the ribs protect the heard and lungs, skull protects the brain, pelvis protects the reproductive organs. 3. Movement - level systems moving, enables breathing. 4. Storage - stores calcium and phosphorus and fat for energy under harsh conditions. 5. Haemopoiesis - red bone marrow which produces new red and white blood cells along with platelets. Cartilage Hyaline - is found in joints and is usually protected and covered. It has no blood or nerve supply and this is good because there is no pain experienced, until too much of it is scraped off and the bone can be seen. It cannot be repaired as there is no blood or nerve supply, hence the negative side. Fibrocartilage - is found between the vertebrae. The outside layer is hard but the inside is a 'pulpy' layer which helps distribute the weight evenly. Elastic Cartilage - is found in the ear mostly and has high amounts of elastic fibres. Bone Tissue Compact bone - the external layer of bone and gets its name due to its property. The dense structure means that there are very little air holes. Spongy (cancellous) bone - has a spongy appearance and is made up of bars of bone with marrow spaces in between. These are filled with the red blow marrow which help produce the blood.

4 Structure of Long Bone Epiphyses - the 2 ends of the bone. Articular (joint) cartilage. Diaphysis - the shaft. Contains bone marrow and nutrients. Heavy. Epiphyseal - line under the Epiphyses. Growth plate. Metaphysis - the connection between Epiphyses and Diaphysis. Bone Formation Endochondral Initiates as cartilage and eventually bone infiltrates (enters) in, to start replacing the cartilage with bone. This process starts from 6th week. Hyaline cartilage begins transformation at around 8th week. Diaphysis (shaft) forms first and then the Epiphysis. It does this by the formation of superficial layer on the outside of the cartilage, this eventually infiltrates the cartilage and starts to grow in length and diameter. Intramembranous Includes flat bones of the skull, clavicle and sesamoid bones. Classification of Bones

5 Bone Markings Articulating Surfaces Condyle - ends of long bones (ball and dish rolling) - smooth. Facet - connect one vertebrae to another vertebrae - gives flexibility in the spine. Head - proximal (closer to origin) point - the ball like part. Trochlea - medial portion of the articular surface of the elbow joint. Extensions and Projections Crest - connect to head of Femur. Epicondyle - end of the condyle (for e.g. Connecting to the elbow). Protuberance - bony outgrowth - back of skull (neck muscle attachment). Spine - pokey bit of the vertebral column. Tubercle - Tuberocity - Passages and Cavities Foremen - the whole at the back of the skull, leading to the spinal chord. Sinus - found in the bones of the face and connecting with the nasal cavity. Meatus - an opening to the ears. There are about 206 bones (average) in the human body.

6 Vertebrae There are around 33 vertebrates in the vertebral column and are divided into 5 different sections: 1. Cervical 2. Thoracic 3. Lumbar 4. Sacral 5. Coccyx