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| Question | Answer |
| List the 5 things that allow us to move | Muscles Tendons Ligaments Cartilage Sketeton |
| Muscles work as... | Antagonistic pairs |
| A muscle which contracts to cause extension of a joint is called a... | Extensor |
| Tendons join... | Muscle to bone |
| Properties of tendons | White fibrous tissue Bundles of collagen fibres Strong but relatively inelastic |
| Ligaments attach... | Bone to bone |
| Properties of ligaments | Yellow strong but elastic tissue. |
| Function of cartilage | A shock absorber which absorbs synovial fluid. |
| Properties of cartilage | Hard, flexible tissue made of chondrocytes w/in an org matrix of collagen fibres Elastic Able to withstand compressive force |
| What is bone made of? | Bone cells embedded in a matrix of collagen and Ca salts. |
| What is 1 property of bone? | Particularly strong under compression. |
| Why do we have synovial fluid? | As a lubricant to reduce friction in joints. |
| When the myosin head binds to the actin what does it form? | An actomyosin bridge |
| What causes the mysoin head to detach from the actin? | Free ATP binding to the m. head |
| When the sarcolema is depolarised what is released, from where to where? | Stored Ca2+ from the sarcoplasmic reticulum into the sarcoplasm. |
| In the sliding filament theory what do calcium ions bind to and what does this cause? | It binds to troponin, which changes shape, pulls on tropomyosin on the actin, causing it to move and expose myosin binding sites. |
| Describe aerobic respiration | The splitting of the respiratory substance to release CO2 as a waste product and reuniting of H w/ O2, with the release of large amounts of energy. |
| What is the overall equation for aerobic respiration? | C6H12O6 + 6O2 --> 6H2O + 6CO2 + ATP |
| Where does glycolysis occurr? | In the cytoplasm |
| What is the first step of glycolysis and what is it called? | Phosphorylation with 2 ATP of glucose to make it more reactive 2GALP. Called pump priming |
| What is the net input net output from glycolysis? | Input: 1 glucose Output: 2ATP, 2NADPH, 2 pyruvate |
| Where does the Krebs cycle occurr? | Matrix of mitochondria |
| What is the net output per pyruvate molecule during the links reaction & Krebs cycle? | 1 NADPH, 1 CO2 - links 3 NADPH, 2 CO2, 1 ATP, 1 FADH |
| How is ATP produced in the Krebs cycle? | Substrate level phosphorylation |
| The inner mitochondrial membrane is ________ to protons. | Impermeable |
| How many ATP does each NADH and FADH molecule produce? | 3 / NADH 2 / FADH |
| What is the theoretical maximal ATP yield from respiration? Where does each ATP get produced? | 38 2 from glycolysis 2 from Krebs 2FADH x 2ATP = 4 10NADH x 3ATP = 30 (2 from links, 6 from Krebs, 2 from glycolysis) |
| Describe chemiosmosis | H's released from H carriers. They split into H+ + e-'s. e-'s move along ETC in a series of redox reactions and lose energy as they go. The energy is used to actively pump H+ ions across mit. inner mem. Inter-mem space now has a higher H+ conc than the matrix so an e-chem grad. = set up. H+ ions move down their e-chem grad. to the matrix through proton pores on stalked particles. The ATPase catalyses ATP synthesis. |
| What happens after chemiosmosis to form water? | H+ ions combine with e-'s accepted by the final e- acceptor oxygen, to produce water. |
| What is the net output of anaerboic respiration? | 2ATP + lactate |
| In aerobic respiration how is NAD re-produced for glycolysis? | By the ETC where NADH gives up its H+ and e-'s for chemiosmosis. |
| How is NAD regenerated in anaerobic respiration? | The pyruvate from glycolysis accepts H's to form lactate and oxidise the NADH to NAD. |
| What is creatine phosphate and what is is used for? | A store of energy in muscle fibres which supplies energy needed for ATP before extra oxygen can be supplied during exercise. |
| Describe and explain the effect of lactate | It forms lactic acid and releases H+ ions lowering the pH. This can inhibit enzymes by neutralising negatively charged groups in their active sites so that the substrate may no longer bind. It also causes cramps when it builds up causing you to stop or slow down. |
| Why do you breathe heavily after a race? | Because oxygen is required to oxidise lactate back to pyruvate. This is post-exercise oxygen consumption. |
| Reasons for expected oxygen debt being smaller than EPOC | We need more oxygen for: restoring creatine phosphate levels re-oxidising myoglobin in muscles increased rate of all chemical reactions muscles of diaphram and ribs need more due to heavier breathing HR = elevated so cardiac muscles need more oxygen. |
| How does creatine phosphate work? | It is hydrolysed to release energy used to regenerate ATP from ADP + Pi |
| Av HR for a male is | 70bpm |
| Define: myogenic property of the heart | It can contract without external nervous stimulation. |
| Which node is described as a pace maker? | Sinoatrial node |
| What does the atrioventricular valve do? | It redirects the impulse through the Purkyne fibres in the bundle of His after a slight delay. |
| During atriole systole which valves are open and which are shut? | AV open SL shut |
| During ventricular systole which valves are open and closed? | AV shut SL open |
| Why is the impulse through the heart delayed just before ventricular systole? | To ensure complete atrial systole |
| Valves during diastole... | AV open SL shut |
| What causes low pressure in the heart chambers during diastole? | Elastic recoil |
| What does ECG stand for? | Electrocardiograph |
| On an ECG what does each of the P, QRS and T section of the graph represent? | P is depolarisation of the atria QRS is depolarisation of the ventricles T is repolarisation of the ventricles |
| Polarised = ______ Depolarised = ______ | Polarised is becoming negative Depolarised is becoming positive |
| Cardiac output = ... (dm3/min) | Stroke volume (dm3) x HR (bpm) |
| Define cardiac output | The volume of blood pumped out of the heart per minute |
| Define aerobic capacity | The ability to take in, transport and use oxygen. |
| Define stroke volume | The volume of blood the heart pumps out each beat. |
| Where is the cardiovascular control center? | Medulla |
| Is the autonomic nervous syt. involuntary or voluntary? | Involuntary |
| What are the 2 parts to the autonomic nervous system and what do they do? | Sympathetic - excitatory Parasympathetic - inhibatory |
| How are baroreceptors used? And what is it an example of? | They are pressure receptors in the carotid arteries which are stretched when BP increases. They send nerve impulses to the CVC through parasympathetic nerves causing HR to decrease and vasodilation which decreases the BP. NEGATIVE FEEDBACK |
| Describe the role of stretch receptors during exercise? | They send nerve impulses from skeletal muscles and the walls of the heart when stimulated during exercise by increased vagus return to the heart and use of muscles. CVC then sends more sympathetic nerve impulses to the SAN to increase HR so oxygen is transported more quickly to the muscles. |
| What hormone can cause an anticipatory increase in HR? | Adrenaline |
| Describe the effects of adrenaline and from where it is released. | Released from adrenal glands above kidneys. Has direct affect on SAN increasing HR and causes dilation of arteries supplying skeletal muscles and constriction of those supplying non-essential organs to maximise blood flow to active muscles. |
| Where is the ventilation centre? | Medulla oblongata |
| How (briefly) does the VC regulate rate and depth of breathing? | Via chemoreceptors in the arteries and stretch receptors in the bronchi. |
| Define: tidal volume | Volume of air entering and leaving the lungs at each natural resting breath. |
| Define: IRV | Volume of air taken in over the normal inspired TV when you breathe in as deeply as possible. |
| Define: ERV | Volume of air that can be expelled over and above normal expired TV when you force air out of the lungs as hard as possible. |
| Define: vital capacity | TV + IRV + ERV The volume of air that can be breathed out by the most vigorous possible expiration following the deepest possible inspiration. |
| Define: residual volume | Volume of air left in the lungs after the strongest possible expiration. |
| Inspiratory Capacity, IC = ... | TV + IRV |
| Ventilation rate = (dm3/min) | TV x freq. of inspiration / minute |
| What is a muscle made up of? | Bundles of muscle fibres bonded together with connective tissue. |
| Describe a muscle fibre | A single long multinucleate cell surrounded by cell surface mem - the sarcolemma. |
| Describe the sarcoplasmic reticulum | A network of internal membranes running through the sarcoplasm which stores and releases Ca for muscle contraction. |
| What is a muscle fibre composed of? | Numerous myofibrils made up of a series of repeating units called sarcomeres consisting of thin actin and thicker myosin filaments. |
| What is the I band, A band and H zone in a myofibril and which change during contraction? | I band = actin H zone = myosin A band = overlap + H zone H and I decrease during contraction A band stays the same because it is always the length of the myosin. |
| Slow twitch fibre is AKA... | oxidative |
| Fast twitch fibre is AKA... | glycolytic |
| Everything about a slow twitch fibre | Many mitochondria. Large amount of red myoglobin. Associated w/ numerous capillaries. Specialised for slower sustained contraction. Can cope with long periods of exercise w/o fatigue. relys on glucose and continues to produce ATP when O2 is available. |
| Everything about fast twitch fibres | Few mitochiondria. V. little myoglobin Relatively few blood vessels. Looks much paler than slow twitch. Specialised for rapid, intense contractions. ATP is almost entirely from anaerobic glycolysis. Fatigue easily due to rapid build up of lactate. Relatively high levels of creatine phosphate. |
| Define: Homeostasis | The maintenance of a stable internal environment. |
| Thermoreg is controlled by... | the hypothalamus |
| What are the 4 methods of energy transfer? | Radiation Conduction Convection Evaporation |
| If body temperature increases too much what is the response of the effectors? | Sweat glands produce more sweat. Vasodilation. Hair erector muscles relax. Sphincter muscles relax and the shunt vessels are closed. |
| If body temperature decreases too much what is the effector response? | Ateriovenous shunt opens and sphincter muscles of superficial arterioles contract. Hair erector muscles contract. Vasoconstriction. Skeletal muscles contract causing shivering. Adrenal medulla glands increase adrenaline production. The liver is stimulated to raise metabolic rate. |
| Advantages of exercise | Lowers BP and risk of CVD and HD Increases HDL decreases LDL Helps maintain a healthy weight Increases sensitivity of muscles to insulin so improves blood glucose regulation. Increases bone density. |
| Disadvantages of exercising too much | Immune surpression Joint wear & tear |
| Suggested causal mechanism for immune suppression due to overtraining | Number and activity of T killer cells, phagocytes, B cells and T helper cells so specific immune response is decreased. The inflammatory response in muscles due to damaged fibres caused by heavy exercise may decrease available non-specific immune response. |
| Disadvantages of exercising too little | Obesity and diabetes (type II) |
| 3 medical technologies enabling those with injuries and disabilities to take part in sport | Keyhole surgery Prosthesis Medicalimaging |
| Define a prosthesis | An artificial body part used by someone w/ a disability to enable them to regain some degree of normal function or appearance. |
| Define doping | Use of drugs to enhance performance in sport. |
| List 8 banned substances | Anabolic steroids Hormones and their releasing factors Beta-2-agonists Hormone agonists Diuretics Stimulants Narcotics Beta-blockers |
| What is blood doping? | Having a blood transfusion to remove their own blood causing the body to make more RBCs and then putting the blood back so their RBC count is raised. |
| What is gene doping? | Any attempt to change the genetic make-up of cells to enhance sporting performance. |
| What are anabolic steroids for? | Building muscle mass |
| What is EPO and what does it do? | Erythropoietin Stimulates RBC production |
| What are hormone agonists? | Chemicals which mask or change the action of another hormone. |
| What do diuretics do? | Increase urine production diluting traces of illegal substances. |
| What are narcotics? | Powerful pain killers that allow athletes to ignore pain and compete harder. |
| What do beta-blockers do? | Block the hearts response to adrenaline and decrease HR. |
| What are 2 ethical standpoints? | Relativist or absolutist |
| Arguments for doping | Up to the athlete to weigh risks May be only way for some to compete at a higher level There is already inequality of competition due to training and resource access differences. If it is acceptable to pay to sleep in an o2 tent or at altitude to raise RBC count why not through blood doping? |
| Arguments against doping | Athletes do not make properly informed decisions New drugs are not affordable to everyone. Heath risks It isn't fair if some take drugs Others may feel under pressure to take drugs if their competitors decide to and may have to in order to stay at the same level. |
| What is the transcription initiation complex? | RNA polymerase and associated transcription factors which bind to the promoter region. |
| How is transcription prevented? (2 ways) | Repressor molecules binding to the promoter region blocking attachment sites. Repressors attaching to transcription factors, preventing them forming an initiation complex. |
| What are hormones? | Chemical messages released directly into the blood from endocrine glands. |
| What type of hormones are 1) testosterone 2) EPO | 1) steroid 2) peptide |
| How do anabolic steroids work? | Pass through cell membrane and bind w/ receptor molecules. Carried to the nucleus where the hormone/receptor complex acts as a transcription factor. It binds to the DNA and switches on particular genes linked to protein synthesis so bigger and stronger muscles are produced. |
| How do peptide hormones work? | Bind to receptors on the cell surface mem Mem. bound complex activates a 2nd messenger in the cell cytoplasm and triggers a protein kinase cascade. This usually involves activation of several different proteins until the final product enters the nucleus. The final prod acts as a TF switching on specific genes. |
| Describe the changes in the heart that bring about increased CO | AVN delay decreases SAN activity increases HR increases Strength of ventricular contraction increases Increased vagus return so heart muscle stretches |
| What is a cruciate ligament? | In the knee behind the knee-cap In a cross shape of 2 ligaments Joins bone to bone |
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