BODY IN MOTION
Y1 SEMESTER 1
These notes were written using learning outcomes as of 2021/2022
Click on link below for a document version of the notes:
Anatomical Planes, Cells, Tissues and Histology
We have tried our best to keep all our notes accurate and up to date. However this is the first year these notes have been sent out so we would love your help to improve them. If you notice any mistakes or have any edit suggestions, please email me s1803407@ed.ac.uk
ANATOMICAL TERMINOLOGY
Anatomical Planes
Anatomical position:
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Head facing forwards
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Standing upright
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Arms by side
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Palms forward (supinated)
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Feet slightly apart
Planes:
Sagittal plane: cut front to back
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Cardinal/median/principle plane: sagittal plane through midline
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Parasagittal plane: sagittal plane off midline
Transverse plane: cut through the middle (e.g. CT scans)
Coronal plane: cut side to side (e.g. brain scans, dissections)
Spatial Relationships
Superior: closer to head
Inferior: closer to feet
Medial: closer to midline
Lateral: further away from midline
Proximal: closer to attachment / trunk
Distal: further from attachment / trunk
Anterior/Ventral: front
Posterior/Dorsal: back
Rostral: closer to nostril
Caudal: closer to ‘tail’
Superficial: closer to skin (e.g. superficial wound)
Deep: further from skin
Movements
Flexion and extension = opposite direction on lower side of body to upper e.g. shoulder flexion brings arm forwards, hip flexion brings the thigh back.
Flexion at ankle (bringing toes up) = dorsiflexion
Extension at ankle (pointing toes) = plantar flexion
Abduction = alien abductions take you away and abduction takes the limb away
Abduction and adduction happening repeatedly = jumping jacks (star jumps)
Circumduction = hand or foot moves in a circle
Rotation at the shoulder will look like the hand is turning, but the effect is on the arm
Supination = when hands are supinated, you can hold a bowl of sop
Cells and their components
https://byjus.com/biology/cell-organelles/
Plasma membrane- Phospholipid bilayer with hydrophilic heads and hydrophobic tails embedded with sugars and proteins. Its main function is to control the entry and exit of substances
Nucleus- Largest organelle, contains DNA, nucleolus involved in the synthesis of ribosomes. Skeletal muscles have many nuclei.
Mitochondria- Produce energy for aerobic respiration, double walled with cristae. There are high numbers in cells that have high energy demands such as muscles.
Endoplasmic reticulum
· Smooth- responsible for synthesising lipids and steroid hormones as well as drug detoxification
· Rough- studded with ribosomes responsible for protein synthesis to be exported from the cell.
Ribosomes- Made up of RNA and protein, important for protein synthesis from amino acids using RNA as a template.
Golgi Apparatus- stack of membrane bound sacs (cisternae). Important for export of proteins. Proteins are received form the ER where they are packaged into vesicles and stored until needed. Vesicles move to the plasma membranes, fuse with it and contents expelled by exocytosis. They also produce lysosomes.
Lysosome- spherical vesicles contain enzymes used to breakdown large molecules within the cell eg DNA, RNA, proteins. Internally acidic (pH5). Once broken down into smaller fragments and can be extruded or recycled.
Cytosol- pH7 is the watery fluids that houses organelles. The cytoplasm by contrast is the name given to all cell contents excluding the nucleus.
Cytoskeleton- Network of protein fibres that give the cell its shape and allowing the cell to move
Catalog: Cytoskelton - page 1 of 6 - gentaur.com
Composed of:
· Microfilaments- provide structural support and allow contractions
· Microtubules- larger fibres involved in movement
· Centrosome- Directs organisation of microtubules. Pair of centrioles are important in cell division.
· Intermediate filament- support for microfilaments and microtubules
Tissues
Extracellular matrix- Is made by cells and exported to fill the extracellular space. It differs between tissue types. For example epithelial tissue is formed from sheets of cells with little ECM whereas connective tissue has a high amount of ECM and comparatively few cells present.
Epithelial
Structure is closely related to functions of protection, secretion, and absorption. There is continuous cell division in the basal layers to protect from wear and tear.
They can be simple (a single layer of cells) or stratified (multiple cell layers).
Simple epithelial tissue
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Squamous- flattened cells attached to a basement membrane. Lines the heart, blood vessels, lung alveoli and collecting ducts of kidney nephron.
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Cuboidal- cube shaped cells attached to a basement membrane, forms kidney tubules and some glands. Has an important role in secretion, absorption, and excretion.
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Columnar- Rectangular- shaped cells attached to a basement membrane. Found in the stomach, small intestine, trachea, fallopian tubes, gall bladder and can be ciliated.
Animal tissues. Covering epithelium. Atlas of Plant and Animal Histology. (uvigo.es)
Stratified epithelial tissue
· Stratified squamous epithelium
o Keratinised stratified epithelium- dry surfaces, skin, hair and nails. Top layer of cells not nucleated and contain keratin. Helps skin to have a waterproof layer.
o Non-keratinised- moist surfaces protect from drying out. Mouth pharynx, oesophagus
· Transitional epithelium- Pear shaped cell, only found within the urinary tract and protects from chemicals
· Pseudostratified epithelium- Gives the impression of multiple cell layers but each cell is attached to a basement membrane. Nuclei at different levels. Pseudostratified columnar ciliated epithelium is found within the respiratory tract only, where the cilia act as a mucociliary escalator is the self-clearing mechanism of the airways in the respiratory system.
Connective tissue
Most abundant tissue, consists of cell embedded in ECM and the main functions are binding/structural support, protection, transport, insulation.
Loose (alveolar) connective tissue- most abundant connective tissue type. Has a semi-solid matrix of collagen and elastin fibres containing fibroblasts (synthesis ECM and collagen), adipocytes (fat cells), mast cells and macrophages (both immune cells). It connects and supports other tissues e.g., under skin and between tissues.
Adipose tissue- Alveolar tissue matrix containing adipocytes. Adipocytes contain large fat globules.
o White adipose tissue- about 20-25% BMI in healthy adults and is a thermal insulator and energy store.
o Brown adipose tissue- found in newborn, highly vascularised and vastly reduced as you develop.
Reticular tissue- found in lymph nodes and organs of the lymphatic system. Matrix consists of reticular fibres. Cells-present are reticular cells and white blood cells
Histology - Types of Connective Tissue (histologyguide.org)
Dense connective tissue- low cell numbers but high in fibre content and can be fibrous or elastic
o Fibrous- collagen fibres in closely packed bundles. Fibroblast cells sit between fibres e.g., ligament and tendon. Very strong periosteum (covering on bones).
o Elastic- Elastin fibres secreted by fibroblast cells. Tissue has a high degree of recoil. Found in organs where change of shape is normal e.g., blood vessels, lungs
Cartilage- Chondrocytes (cartilage cells) embedded in a collagen and proteoglycan matrix.
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Hyaline cartilage- on the ends of long bones and has a role in shock absorption.
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Fibrocartilage- Additional fibres within matrix e.g., intervertebral disc, knee joint
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Elastic fibrocartilage- Elastic fibres gives it a springiness- outer ear
Bone- Bone cells (osteocytes) embedded within a mineralised collagen matrix
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Osteocytes- mature bone cells that reside deep within the matrix.
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Osteoblast- Lay down new bone matrix
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Osteoclast- remove bone matrix
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Compact bone- dense bone found on the outside of a bone shaft
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Spongy/ cancellous bone- is more aerated and made up of different struts of bone called trabeculae in the ends of bones.
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Tendons- attach muscle to bone
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Ligaments- attach bone to bone
Three Types of Muscle | Muscle Tissues (histologyguide.org)
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Skeletal- striated (stripes) formed form multinucleated muscle fibres. Myoblast fuse together to produce a single myocyte. When looking at microanatomy look at how its been cut to help identify structures.
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Smooth- Non-striated and under involuntary control. Useful in propelling contents along tubes by peristalsis (rhythmic contraction. Mononucleated found in the gut tube, ureter etc.
Cardiac- Striated under involuntary control. Mononucleated and are specialised cells that make up the walls of the heart. Intercalated discs between cells help to communicate with each other and propagate wave of contraction.
Parts of a Neuron and Their Functions with Labelled Diagram (sciencefacts.net)
Nervous- cell bodies are found within the central nervous system and axons are found within the peripheral nervous system. Flat in structure and there are bundles of axons within nervous tissue.
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Neurons- excitable cells which initiate, receive, and transmit information.
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Glial cells- non-excitable cells, support the neurons and are more numerous.
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Astrocytes, oligodendrocytes, ependymal cells, microglia
Cell junctions
Functional classification of junctions- occluding, anchoring, and communicating
Occluding
· Tight junctions- to seal cells together to prevent molecules from leaking to another cell or across a boundary.
Anchoring junctions- Main role is to mechanically attach cells (and their cytoskeleton) to adjacent cells or to the ECM.
o Actin filament attachment sites- There are cell-cell junctions (adhering junctions) and cell-matrix junctions (focal adhesions)
o Intermediate filament attachment sites- These are cell-cell junctions (desmosomes) and cell-matric (hemidesmosomes)
Communicating junctions- Main role is to control the passage of signals (chemical or electrical) from one cell to another. Most cells are limited to their neighbours via gap junctions eg cardiac and smooth junctions.
o Gap junctions- intercalated discs
o Chemical synapses
o Connexins- channel forming
Visualising Tissue
· Tissue samples need to be processed to study them by microscopy. Technique known as histology. Tissue is sliced into thin sections and stained.
· Tissue biopsy- Fixation- Processing (series of steps to reduce the amount of H20 in the sample) – Embedding (embed in wax to get a wax block) – Sectioning (Microtome to get very thin ribbon to put into slide)- Staining (for different cells and organelles) – Visualisation (under a microscope)
Stains
· H&E- Haematoxylin and Eosin. Cytoplasm and matrix (pink) and nuclei (purple)
· Massins trichrome- connective tissue stain. Connective tissue (green) and Nuclei (black)
· Von rossa- mineral stain (black) e.g., bone
· Oil red O- fat globule stain (red)
· Alizarin red- mineral stain (red)
Respiratory epithelium in the larynx