par simran chana Il y a 11 années
881
Plus de détails
Immediate respomse and the same for all pathogen
Slower response and specific to each pathogen
Humoral reponse
Monoclonal antibodies
Used in Seperation of chemicals Cancer treatment Transplant surgery
Be able to be stored
Have few side effects
Be economically available
Many different strains of the same virus
Pathogen may mutate frequently
Disease may develop shortly after vaccination has been given
Antibodies made by the body in response to an antigen
Antibodies given to you
A type of white blood cell responsible for the immune response
T Lymphocytes Associated with cell mediated immunity
Responds to foreign material inside body cells
B lymphocytes Associated with humoral immunity
Produces antibodies Responds to foreign material outside body cells
Pathogen is engulfed by phagocytosis Phagocytes places pathogen on cell surface membrane Receptors on T helper cell fit onto antigens Activate T cells divide by mitosis into Memory cells B cells
Fats and oils make up triglycerides Each fatty acid forms a bond with glycerol in a condensation reaction When hydorlysed triglycerides produce glycerol and three fatty acids
Hydrophillic head: Attracts water Hydrophobic tail: Repels water
Fatty acid replaced by phosphate group
Main role in plasma membrane
Provide flexibility of membrane Transfer lipid soluble substsances Energy source Protection
The movement of ions and molecules from a region of low concentration to high concentration using energy
Active process Requires energy Carreier proteins are required for the ions and molecules to pass through
Water potential is the pressure created by the water molecules
The greater the number of water molecules, the higher the water potential
The movement of water from a high water potential to a low water potential
The movement of particles from an are of high conencentration to an area of low concentration
Facilitated Diffusion
Passive process Down a concentration gradient Occurs in plasma membranes Protein channels allow water soluble molecules to pass through
Glucose is absorbed through thte walls Increases surface area Increases rate of absorption Villi sistuated between lumen
Co-transport
1. Sodium ions actively transported out of epithelial cells by sodium pottasium pump 2. Higher concentration in lumen than inside epithelial cell 3. Sodium ions diffuse down concentration gradient through protein carriers 4. Sodium ions flood back, coupled with glucose, into cell 5.Glucose passes through blood plasma by facilitated diffusion using another protein carrier
Efficiency
Able to move
Maintain concentration gradient
Increase surface area
Very thin Short diffusion pathway
Ingredients
Water-Rehydrate tissues Sodium- Replace ions lost Glucose- Stimulate uptake of ions Pottasium-Replace ions lost
Why water isnt helpful
Water is not absorbed by the intestines It doesnt replace ions that are lost
Hydrophillic head pointing inwards interacting with water in cytoplasm Hydrophobic tail pointing out avoiding interaction with water Function is to allow lipid souble substances to enter and leave the cell
Fluid mosaic model
Fluid- Phospholipids can freely move Mosaic- Proteins varies in shape, size and pattern
Site of protein synthesis
Smooth ER
Tubular Synthesise,store and transport lipids and carbohydrates
Rough ER
Ribosomes present on outer surface Provide large surface area for protein synthesis
compact and consists of stacks of membranes
Contain enzymes which break down material ingested by phagocyte cells Release enzymes outside of the cell Digest worn out organelles
Nuclear envelope- Controls entry and exists of material in and out of cell Nuclear pores- Passage of large molecules Nucleouls- Makes up nucleus, makes ribosomes Chromatin-DNA
Controls cell activity
Double mebrane-control entry and exits Cristae-increases surface area
The process where cells are broken up and the organelles are seperated Cold- reduce enzyme activity Isotonic- prevent organelles bursting.shrinking Buffer- maintain a constant pH
Ultarcentrifugation
Fragments are centrifuged which spins the tubes at very high speeds in order to create a centrifugal force
Homogenation
Cells are broken up by a blender releaseing organelles from the cells Fluid is filtered to remove any complete cells or large pieces
Produces a 2-D image Staining is required Specimen must be thin
MInimum distance 2 objectrs need to be in order to appear sepearte items Greater resolution means greater clarity, image produced is clearer and more precise
Produces a 3-D image Low resolving power
Made up of chains of monomers Repeated chains are called polymers Carbohydrates are made up of carbon, oxygen,hydrogen and nitrogen
Monosaccharide's join together in condensation reactions to form disaccharides which are help together by Glycosidic bonds Glucose and glucose gives you maltose Glucose and fructose gives you sucrose Glucose and Galactose gives you lactose
Carries food from the mouth to the stomach
A muscular sac that produces enzymes It stores and digest food
Long muscular tube Food is further digested by enzymes Inner wall is folded into villi which provide a large surface area
Absorbs water Water that is reabsorbed comes from secretion of many digestive glands This is why food becomes drier and thicker in consistency and forms faeces
Secretes enzymes like amylase which breaks down starch into maltose
Breakdown
Lactose intolerance
Reduction of lactase can cause lactose intolerance as the person is unable to digest all the lactose they consume When the lactose reaches the large intestine, it gets broken down however forms a large volume of gas which results in nausea, bloating, diarrhoea and cramps
Physical
Large food molecules are broken down into smaller pieces by the teeth. This allows ingestion and provides a large surface area for chemical digestion
Chemical
Breaks down large insoluble molecules into smaller soluble ones using enzymes. The enzymes hydrolyse (split the molecules using water) the food molecules. Once hydrolysed they are absorbed from the small intestines into the blood These molecules are them incorporated into the body tissues and used in processes within the body. This is called assimilation.
Non-competitive
Bind elsewhere on the enzyme but not the active site
Competitive
Bind to the active site of the enzyme
pH
Each enzyme has a optimum pH pH changes reduce the effectiveness of an enzyme by altering the shape of the active site, causing the bonds in the tertiary structure to break
Temperature
Increasing the temperature increases the kinetic energy of the molecule. This results in greater collisions increasing the rate of reaction Too high temperatures can cause the hydrogen bonds and other bonds to break, altering the shape of the active site so the enzyme denatures
Small region called the active site The molecule on which the enzyme acts is called the substrate When the active site and substrate bind it forms an enzyme substrate complex This is held by temporary bonds
Basic monomer units which combine together to form polymers called polypeptides Each amino acid has a central carbon atom which is bonded to 4 other chemical groups: -Amino acids (-NH2) -Carboxylic group- (-COOH) -R group- Variety of different chemical groups -Hydrogen group- (-H)
Primary structure- Sequence of amino acids found in polypeptide chains Sequence determines properties and function Secondary structure- Forms α helix 3-D shape due to the hydrogen bonds Tertiary structure- Shape forms by folding of polypeptide helix Consists of disulphide, ionic and hydrogen bonds The 3-D structure controls how the protein functions Quaternary structure- Arises from a number of polypeptide chains joined together to form a protein molecule
Control of blood flow
1. Wave of electrical activity spreads through the SAN across both atria, causing them to contract 2. Layer of non-conductive tissue prevents the wave crossing the ventricles 3. The wave passes through the AVN which is between the atria, this conveys an electrical wave between ventricles along the bundle of His 4. The bundles of His conducts the wave through the atrioventricular septum between the base of the ventricles where it branches into smaller fibres 5. The wave releases from the fibres causes the ventricles to contract
Ventricular systole
Blood is pumped into the pulmonary arteries and aorta Semi lunar valves are open Left and right atrioventricular valves closed Ventricles contract (Atria relax, Ventricles contract, pushing blood away from the heart through pulmonary arteries and the aorta
Atrial systole
Atria contract to push remaining blood into ventricles Semi lunar valves closes Left and right atrioventricular valves open Blood pumped from atria to ventricles (Atria contract, pushing blood into the ventricles. Ventricles remain relaxed)
Diastole
Blood enters atria and ventricles from pulmonary veins and vena cava Semi lunar valves are closed Left and right atrioventricular valves open Relaxation of ventricles draws blood from the atria (Atria are relaxed and fill with blood, Ventricles are also relaxed)
Atria- Receive blood returning to the heart Ventricles- Pump blood to the entire body Semi lunar valves- Prevent back flow in the aorta and pulmonary artery Atrioventricular valves- Prevent back flow between the left atrium and right ventricle and right atrium and left ventricle Pocket valves- Prevent back flow in the veins that occur throughout the venous system
Vessels Chamber Blood Takes blood from/to Aorta Left ventricle Oxygenated All parts of the body except the lungs Vena cava Right atrium Deoxygenated Brings deoxygenated blood back from tissues in the body Pulmonary artery Right ventricle Deoxygenated To the lungs Pulmonary vein Left atrium Oxygenated Brings oxygenated blood back from the lungs
1. Blood enters the atrium then into the ventricles 2. The left ventricl has more muscle as it has to contract much more strongly to push blood around the whole body
Coronary heart disease
Affects the coronary arteries which supply the heart muscle with oxygen and glucose Blood flow may be impaired due to the build up of fatty deposits know as atheroma This can lead to a myocardial infarction
Atheroma
Myocardial infarction
Reduced supply of oxygen to the heart, which is a result of blockage in the coronary arteries The heart stops beating because the blood supply is completely cut off
Thrombosis
If the atheroma breaks through the lining of the artery walls, it forms a rough surface which interrupts the smooth blood flow This may cause a blood clot to form, which will prevent the supply of blood getting to the tissues beyond it
Aneurysm
Atheroma weakens the artery walls These end up swelling to form a blood filled structure called an aneurysm This can cause the artery to burst, leading to loss of blood to the region of the body served by the artery
Fatty deposit that forms within the walls of an artery Begins as fatty streaks which are made up of cholesterol, fibres and dead muscle cells They form in the lumen of an artery causing it to narrow and reduce blood flow
Gas exchange surfaces
Narrow capillary walls - Slow down flow of blood to allow more time for diffusion - To make sure red blood cells are squashed against the capillary walls
Large SA:Vol ratio Thin Partially permeable Have movement of internal and environmental medium (Air and blood)
Trachea- Flexible airway supported by cartilage Bronchi-two divisions of the trachea Bronchioles-Sub division of the bronchi Alveoli-Minute air sacs Diaphragm- A sheet of muscle that seperates the thorax from the abdomen Intercostal muscles- Lie between the ribs Internal intercostal muscle- Contraction leads to expiration External intercostal muscle-Contraction leads to inspiration
Asthma
- Allergic reaction to allergens and pollutants - Lining of airways become inflammed - Excess mucus is produced - Muscles contract around the bronchioles
- Difficulty breathing - Tight feeling in the chest - Coughing
Fibrosis
1. Scars arise on epithelium 2. This causes the tissue to thicken and the rate of diffusion of oxygen to decrease
- Shortness of breath - Chronic dry cough - Pain in the chest - Weakness, Fatigue
Emphysema
Elastin around alveoli is permanently stretched so they are unable to force air out and the surface area is decreased
- Shortness of breath - Chronic dry cough - Bluish skin
Pulmonary tuberculosis
Course of infection
1. Bacteria divide in lungs 2. White blood cells ingest bacteria. This causes inflammation (primary infection) 3. Bacteria return after a period of time (secondary infection) 4. Bacteria destroy tissue in lungs. This causes thick scar tissue
Transmission
- Air - Droplets (sneezing, coughing) - Close contact with infected person - Infected milk
Symptoms
- Persistent cough - Tiredness - Loss of appetite
