Lecture 1 , Pt 1 - Cytology, Basic Genetics & Histology Flashcards
Biomedicine, Homeostasis, Body Structure, Cell Components
What is Biomedicine?
Anatomy - structures that form the body
Physiology - How the parts of body work
Pathology - Study of abnormalities
What are the Characteristics of Life?
Metabolism - sum of all chemical processes
Responsiveness - ability to respond to change in environment
Movement - of whole being of individual cells, organs
Reproduction new cells or new individual
Growth - increase in size of number
Differentiation - Development to specialised state
Vital Force / Life Force . Qi
Characteristics of Death?
No breathing
No heartbeat
No brain function
No vital force / Life Force / Qi
What is Homeostasis?
Condition of equilibrium (balance) in the body’s internal environment regulated by body’s internal regulatory processes
Homeostasis Variables - Examples?
Must be between certain narrow parameters to stay in balance:- Core temperature - 36.5-37.5C Water and electrolyte concentrations Blood pressure Blood glucose levels Blood and tissue O2 / CO2 levels pH (acidity or alkilidty) of body fluids Flow of Life Force
Homeostatis Body Fluid Composition / Volume
Body Fluids - Intracellular (inside) or extracellular (outside) eg blood plasma, lymph fluid, interstitial fluid.
Proper functioning of cells relies on interstitial fluid composition.
What are the Homeostasis Control Systems?
Disruptors - change the homeostatic parameter
Detectors - Receptors that detect the disruption
Control Centre - Determines limits within which parameters should be maintained and evaluates input and output
Effectors - Structures that receive output
What is the Feedback System?
Negative - output reverses the input (most body variables eg body temp, blood pressure etc
Positive - strengthens change in the body’s controlled conditions ie reinforces the body eg breastfeeding, child birth, immunity, blood clotting
What is the Body’s Organisation?
Atoms & Molecules - chemical level
Cells - smallest living units in body
Tissues - Groups of cells that work together
Organs - Groups of tissues that work together
Systems - Related organs that have a common function
The Organism - all parts of the body together
Vital Force - The energy that creates life
What are the Systems of the Body?
Skeletal Muscular Reproductive Endocrine Lymphatic Digestive Respiratory Cardiovascular Urinary Integumentary (Skin) Nervous Immune
What are the Body cavities?
Cranium
Thoracic
Abdominal
Pelvic
Diaphragm main muscle of breathing and differentiates thoracic (above) and abdominal (below)
Cell Theory
Living things made up of cells and vital force
Cell is structural and functional unit of all living things
Cell comes from pre-existing cells by division
Contain DNA - hereditary info
All energy flow of life occurs in cells
Cell Memory
Memory in brain but can be stored in individual body cells such as traumatic experiences, negative beliefs
What is Disease?
A disruption of body physiology can cause disease by eg environment, dietary choice, lifestyle choices, drugs etc
What is Metal Toxity & Cell Damage?
Aluminium, mercury and lead can build up in the body and cause damage
Aluminium toxicity has been linked to Alzheimers, can cause damage to neurons in brain and is a risk factor for some cancers eg breast cancer
Aluminium - foil, antisperent, kitchen pans etc
What is Oxidative Stress re Cells?
Oxidative Damage - damage caused to cell by a molecule containing oxygen - called Free Radicals - unstable - highly reactive. Can cause
Vits ACE are antioxidants plus beta-carotene
Define Prokaryotic & Eukaryotic Cells?
Pro contain no nucleus and no membrane binds cell structures. Are smaller . Has a cell wall. Inc bacteria. Cell division - binary fission
Euk - contain a nucleus and membrane-bound organelles. Are bigger. Cell wall only in plants / fungi. Cell division involves mitosis
Cell Components - Cell Wall..who has and what does?
Human cells - no cell wall only a membrane
Plant and fungal have cell walls
Walls provide strength and rigidity and surround membrane
Cell Components - Cell Internally Consists of..?
Cytosol - basic watery fluid
Organelles - small specialised structures within the cell
Cytoplasm - Cell content excluding the nucleus
Cell membrane - Structure?
Flexible, semi permeable, separates the cells external and internal environment. Allows mobility and assists in cell processes such as growth, movement and secretion
Is a phospholipid bilayer, lipids being hydrophobic (water hating) and phosphate heads being hydrophilic - water loving
Membrane is embedded with transmembrane proteins
Membrane controls substance movement in and out of cells
Transmembrane Proteins perform how?
Transport substances in and out of the cells
Helps immune cells to recognise our own cells so the white blood cells do not attack them ie Autoimmune diseases eg Coeliac’s disease
Recognition site for hormones
What is the Phospholipid Layer
Hydrophobic tails face inwards whilst hydrophilic face outwards
Membrane is embedded with transmembrane proteins and other fats such as cholesterol
What are Cell Junctions?
Contact / communication points between the adjacent cell membranes of tightly packed cells. These include
Tight junctions - found in stomach, intestines and bladder. Transmembrane proteins fuse cells together to reinforce the junctions and seal off passageways prevent leaking
Gap junctions - small fluid filled tunnels between neighbouring cells eg nerves
What are the names of the Organelles?
Key organelles in the body:- Nucleus Mitochondria Ribosomes Endoplasmic reticulum Golgi Apparatus Lysomes Cytoskeleton
