Physiology: Human Body Functions and Processes

Physiology: investigation of the processes or functions of living things Why Physiology: in depth understanding of the human body and how it functions The Human Body: 6 Levels of Organisational Levels: 1. Chemical Level: Atoms that create molecules e.g. protein, carbohydrates, DNA, mono...

Physiology: investigation of the processes or functions of living things Why Physiology: in depth understanding of the human body and how it functions The Human Body: 6 Levels of Organisational Levels: 1. Chemical Level: Atoms that create molecules e.g. protein, carbohydrates, DNA, monosaturides 2. Cell Level: (multiple molecules = cells) cells are the structural and functional units of the body. Each cell contains little organs (organelles) which perform functions 3. Tissue Level: (multiple cells joined together create tissues). 4 types → epithelial, connective, muscle, nervous 4. Organ Level: (comprised of two or more types of tissues) 5. Organ System Level: (multiple organs = organ system). 11 organ systems, multiple organs performing a common function 6. Organism Level: a whole living thing (human body) 11 Human Body Organ Systems: 1. Integumentary system (skin system) 2. Skeletal 3. Muscular 4. Endocrine 5. Respiratory 6. Digestive 7. Lymphatic 8. Cardiovascular 9. Male reproductive 10. Female reproductive 11. Urinary Characteristics of Life:  Organisation - 6 levels of organisation → how these levels interrelate to function  Metabolism - chemical reactions taking place to maintain life. The use of energy to perform functions  Responsiveness - read internal or external change and ability to respond and adjust to those stimuli. Control systems = nervous + endocrine  Growth - increase in cell size and/or number  Development - changes over time → fertilisation to death. Differentiation → change in state from immature generalised to mature specialised  Reproduction - creation of new cells → e.g. red blood cells have a lifespan of 3 months (every 3 months they deteriorate and new ones are formed) in order to maintain life Cell Biology: Cell Functions: 1. Cell metabolism + energy use - chemical reactions within the cells often involving energy transfer. Cells can produce energy in order to maintain life 2. Synthesis of molecules: (cells synthesise molecules) - they combine, package and modify different things to create different molecules. Any molecule we need (e.g. protein) cells can make 3. Communication - cells enable chemical and electrical communication between cells. We pick up on different stimuli/changes that occur in the human body due to different environments and our cells are what communicate that to each other to do something or do an action to help enable that change in the environment 4. Reproduction + Inheritance - cells contain DNA molecules which hold the genetic information of an organism Plasma Membrane: → Function: 1. Barriers that separates intracellular fluid from extracellular fluid o Intracellular = all fluid inside the cell o Extracellular = all fluid surrounding the cell (plasma or interstitial fluid) 2. Encloses the cell content (holds it together) 3. Attaches cells to extracellular area (holds it in its place) 4. Helps with communication (brings molecules over the membrane into the call + also takes things from the cell to outside) it facilitates the movement in and out of the cell → Anatomy: Components:  Membrane Lipids: o Phospholipids which form a lipid bilayer (two layers) o Cholesterol  Membrane Proteins: o Integral membrane proteins (sit within) o Peripheral membrane proteins (help with carrying and facilitating molecules moving in and out of the cell) Plasma Membrane Movement: → (How to move things from within the cell to out of the cell or vise versa)  This movement is through or over the plasma membrane (happening all the time)  Plasma membrane is selectively permeable (it is going to selectively choose what to bring into and out of the cell)  Nutrients need to move into the cell + waste needs to move out (move into + between cell) Two Types of Movements: 1. Passive: o Diffusion - movement of solutes from high to low concentration (down a concentration gradient) o Osmosis - diffusion of water only to assist in equilibrium → water moves from less concentrated solution to a more concentrated solution o Facilitated Diffusion - something moves down its concentration gradient but requires a carrier protein. Glucose moves from one side into the cell via the carrier molecules → Carrier molecule enables glucose to move in the direction it needs to move in the direction it needs to move in 2. Active: (energy in the form of ATP is required to facilitate this movement) o Active transport - uses energy to move molecules against a concentration gradient → from low to high (move things from an area where there wasn’t very many to an areas where there was already a lot → for some reason there needs to be more)  Sodium potassium is an example - exchange one molecule for another  Sodium is pushed out of the cell and potassium is brought in  This is achieved through energy (ATP)  ATP is used to facilitate the movement of sodium out and potassium into the cell o Secondary Active Transport:  Two things are happening  Left side is the sodium potassium pump  Sodium is pumped out  Potassium is pumped in  Because sodium is being pumped pumped out, that is setting up a concentration gradient. Putting more potassium outside the cell and less sodium inside the cell  When sodium moves from its high concentration gradient outside the cell and back into the cell where it is low concentration, via a carry molecule. Sodium has the ability to bring other molecules with it (called symport) brings glucose with it  Secondary active transport happens through symport method o Vesicular Transport:  Transport via the formation and release of vesicles (a group of molecules combines a vesicle transport method and is wrapped around them and they can either enter the cell (endocytosis) or (exocytosis) exit the cell Endocytosis: → Phagocytosis = cell eating (larger particles or molecules) → Pinocytosis = cell drinking (something dissolves in a liquid)  o Receptor-mediated endocytosis (INSERT IMAGE) o Exocytosis (INSERT IMAGE Cytoplasm: → Cytoplasm = cytosol + organelles o Cytosol: solution comprised of suspended and dissolved molecules o Cytoskeleton: holds organelles and nucleus in place and supports the cell Nucleus: o Nucleoplasm - watery substance where things are suspended in o Nuclear Envelope - its like a membrane for the nucleus o Nuclear Pores - allow movement of things in and out of the nucleus o Chromosomes - made up of DNA (structural and functional characteristics) o Deoxyribonucleic Acid (DNA) - structural and functional characteristics → held within the nucleus (can’t get out of the nucleus as it is too big) o Ribonucleic Acid (RNA) o Nucleolus - at the centre of the nucleus o Ribosomes - site of protein synthesis → produce proteins used inside the cell and proteins secreted from the cell Endoplasmic Reticulum: → Endoplasmic Reticulum: continuation of nuclear envelope o Rough ER - has ribosomes attached (job is the production of proteins) o Smooth ER - absence of ribosomes (doesn’t produce proteins)  Produces lipids (cholesterol, steroid hormones, phospholipids, carbohydrates)  Detoxification (certain toxins or drugs would make their way to the smooth ER and due to the contents within, it enables processes that detoxify the toxins, breaking them down) Golgi Apparatus: o A series of membranous sacs (like a packing centre) o Modifies, packages, and distributes molecules produced by the endoplasmic reticulum o Changes them to make what the body needs, then distributes them (keep in the cell, push them out around the cell or completely out of the cell to another part of the body) Mitochondria: o Production of ATP (via aerobic → oxygen) o Cell energy plant o Citric acid cycle + electron transport chain o Aerobic o Capacity to increase the number of mitochondria within a cell