Topic 7 Flashcards
Where do muscles bring about movement
At joints
What is antagonistic muscles pairs
Muscle pairs that work together to create movement
Ie one flex one extends
One contract one relax ie bicep and triceps
What is an extensor
Is a muscle that contracts which brings about extension
What is a flexor
A muscle that contracts and brings about movement with the muscle bending
Name all the parts of joint and there function
Synovial fluid-acts as a lubricant allows the joint to move freely
Ligaments- attach bone to bone
Cartilage-it’s absorbs synovial and acts as a shock absorber
Tendon -attach bone to muscle
Fibrous capsule -they aid in enclosing joints
Synovial membrane-they secret synovial fluid that acts as a fluid
What are muscle made up of
Muscle fibres
State the content of a muscle fibres
Mitochondria Cytoplasm Myofibrilis Several nucleus They are stripped
What is the sacromere
A series of contractile units that make up myofobrils
What the two proteins found in sacromere
Actin
Myosin
What two protein molecules are associated with actin molecules
Troponin and troppmyosin
What causes ca ions to be released from the sarcoplasmic reticulum
By nerve impulses arriving at the neuromuscular junction
Describe every stage of the sliding filament theory
Ca ions bind onto the troponin molecule causing it to move this in turn causes tropomyosin to move this action exposes the myosin binding site
The myosin head can now attach onto the binding site on the actin causing a cross bridge to form
The binding of the myosin to actin causes ADP and p1 to be released which means the myosin head no foward as it changes shape meaning actin can move over the myosin toward the sacromere
ATP binds onto the myosin head causing it to detach from the actin then atpase on the myosin head hydrolysis the ATP into ADP and p1
This hydrolysis causes the myosin head to change shape and stand up right so the cycle starts again
What do the troponin and tropmyosin prevent
They prevent the binding of the actin head with the binding site as they block it
What is basal metabolic rate
It’s the minimum amount of energy required to keep us alive(at rest)
What factors are basal metabolic rate dependant on
Age
Gender
Surface area
Body fat
How is ATP made and what is the reaction called
It’s made when an inorganic phosphate combines together wit ADP and the reaction is called phosphorylation
Describe how ATP works to produce energy
A phosphate is removed from the ATP forming ADP and the phosphate is hydrated in water it forms bond and this releases a lot of energy to drive reactions in cells
What is glycolysis and where does it occur
It occurs in the cytoplasm of cells and it’s the intial stages of carbohydrate breakdown
In glycolysis what is glycogen converted into and what’s an issue with its
Glucose but it’s unreactive and stable
Describe the stages in glycolysis
Two phosphate groups are added from ATP molecules to glucose which increases its reactivity
Which is split into two molecules of phosphorylated 3 carbon compounds
Which are then oxidised to produce 2 3 -carbon compounds called pyruvate
The two hydrogen atoms removed during glycolysis what happens to them
They are taken up by coenzyme NAD
What is substrate-level phosphorylation
When a phosphate from immeadiate compound 3Cis transferred to ADP to make ATP
What does the 3c pyruvate do if oxygen is available
It’s passes into the mitochondria (completely oxidised to Co2 and H2o
What are the 2 pathways called
Link reaction
Krebs cycle
Describe what happens in link reaction
Pyruvate is decarbocylated in which co2 is released,dehydrogenated in which 2Hs are removed
The 2 carbon compound that forms combined with Co enzyme A to Acetyl CoA
What happens to the acetyl groups that are produced
They are carried by co enzyme a to the Krebs cycle
What happens in Krebs cycle where does it occur and state what things are produced
It takes place in mitochondria the acetyl compound reacts with a 4C compound to make a 6 C compound and the cycle continues in which the 4C is recreated
4 pairs of hydrogen molecules are made by dehydrogenation
2Co2 molecules are produced by decarboxylation
An ATP is made by substrate level phosphaylation
What happens to the 4 pairs of hydrogen molecules produced in the Krebs cycle
They are taken by hydrogen acceptors co enzyme NAD and FAD to be used in ATP production
Describe each step in ATP synthesis,chemiosis
Step 1-2H+ and electrons are carried by reduced co enzyme to the electron transport chain in the inner mitochondrial memebrane
Electrons pass from one electron carrier to the next in a series of redox reactions,when it recovers the electron its reduced and when it’s passed on its oxidised
As electrons pass along the chain energy is released which is used in moving hydrogen ions into the inter membrane space after moving across the inner mitochondrial membrane (high h+ created)
This creates an electrical gradient as a result a result across the inner memebrane as there’s a large difference of h+ ions across the memebrane,with the intermembrane space being more positive than the matrix
The hydrogen ions will diffuse down this electrical gradient through protein channels in ATP synthase as they pass through channels,ATP synthesis is catalysed by ATP synthase,hydrogen ions cause the active site of the enzyme to change which enables ATP and phosphate ions to bind to the site allowing synthesis of ATP
In the matrix hydrogen atoms are from when h+ electrons combine with each other they also combine with oxygen to form water
Ions
What is the synthesis of ATP called and why
Oxidative phosphorylation
Because oxidation and reduction reaction occur in the electron transport chain
In ATP synthesis how is the electrical gradient created
By hydrogen ions moving across the inner mitochondria membrane and into the intermembrane space
How are the hydrogen ions in ATP synthesis moved
Energy from the electrons passing along the electron transport chain is used in moving hydrogen ions
How does anaerobic respiration differ from aerobic respiration
It doesn’t invovle link reaction,Krebs cycle or oxidative phosphorylation
What happens in anaerobic respiration
Glucose is converted by glycolysis into pyruvate
Reduced nad from glycolysis transfer hydrogen to pyruvate which forms lactate and NAD
The lactate regenerates NAD this enables glycolysis to continue and a small amount of ATP can be produce d
State why oxygen is important in the electron transport chain and what will happen if it’s not present
It act as the final electron carrier of it’s not present the chain will stop working,no reduced NADp will be produced either
What impact does lactate have on muscles and why does it mean anaerobic respiration doesn’t last long
It builds up and in solution forms lactic acid meaning ph falls which inhibits enzymes that catalyse glycolysis reactions
Explain how lactate inhibits enzymes in glycolysis
Lactic acid has hydrogen ions and they neutralise negatively charged groups in the active site of an enzyme
This means it affects the attraction between the charged groups on substrate and on the active site meaning they can no longer bind to each other
What is creatine phosphate used for
It’s used in the immeadiate regeneration of ATP and it’s used when supplying instant energy
What is aerobic capacity
The ability for the body to take in transport and use oxygen
What is meant by VO2
It’s s the amount by of oxygen we consume per minute
What is meant by VO2 max and give the units
It’s the amount of oxygen we consume per minute during maximum aerobic excerise
Min-1 kg-1
What is cardia output and how is it calculated
The volume of blood ejected from the heart in a minute
Stroke volume * heart rate
What is stroke volume
This is each time the ventricle contracts the volume of blood that’s ejected by the left ventricle cm3
What is stroke volume determined by
Venous return which is the amount of blood returning to the heart
When measuring heart rate where do we take a pulse from
Radial wrist and carotid artery
What is meant by the heart by myogenic
It means it can contract without external nervous stimulation
How does the heart contract
The heart muscle cells become depolarised in which the charges are reversed
The change in polarity spreads from cell to cell causing contraction of. The heart
Describe the steps in the contraction of a single heart beat
Depolarisation occurs at the Sinoatrial node which generates an electrical impulse
This impulse spreads across the left and right atria which causes them to contract
It travels to the atrioventricular node and conducts an impulse to the ventricles after a delay of 0.13
The signal then reaches the purkyne fibres after a delay and they conduct the impulses quickly to the apex of the ventricles
The fibres divide into branches that penetrate into the ventricle muscles and these brackets carry impulses to the inner dells within the ventricles and it spreads through the walls of the ventricle
The first ventricular cells are depolarised at the apex of the heart,contractions begin there and travel upwards towards the atria and a wave of contraction is produced that moves up the ventricles pushing blood into the aorta and pulmonary artery
In the contraction of the heart why is the delay important
It ensures the atria have finished contracting and the ventricles have filled with blood before they contract
What is an ECG used for
To measure the electrical activity of the heart
State the four waves in an ECG and what they mean
P-wave- this is when depolarisation of the atria occurs and it leads to atrial contraction(atrial systole)
PR internal-this is the time it takes impulses to be conducted from the SAN across the atria to the ventricles w through the avn
QRS complex- It’s the wave of depolarisation that results in the contraction of ventricles (ventricular systole)
T-Wave- this is during the hearts relaxation phase and repolarisation of the ventricles
What is braclycardia
When heart rate is less than 60 bpm
What is tachycardia
When heart rate is greater than 100 bpm
What is asystole
When there no heartbeat
What is meant by arrhythmia
Arrhythmia-is when electrical disturbances are caused by irregular heart beats
Is
What is the role of the cardiovascular control centre and where is it located
It’s controls heart rate and it’s located in the medulla oblongata
What is the function of the sympathetic and vagus nerve
Sympathetic nerve increases our heart rate by sending impulses to the sinoatrial node
Vagus nerve causes heart rate to slow down
What things does the cardiovascular control detect
Co2 accumulation
Lactate in blood
Reduction in oxygen
Rise in temperature
What impacts does adrenaline have on our heart rate
It has an impact on the sinoatrial node in which it causes heart rate to increase
It causes vasodilation of arterioles that supply muscles and constriction of arterioles that go to the digestive system which maximises blood flow to the active muscles
What is tidal volume
The volume of air we breathe in and out at each breath at rest
What is vital capacity
The max volume we can inhale and exhale on average
What is minute ventilation
The volume of air taken into the lungs in a minute
How is our breathing controlled
By the ventilation centre in the medulla oblongta
What happens in inhalation
The ventilation centre sends nerve impulses to the diaphragm muscles and external intercostal muscles and they contract which brings about inhalation
Describe what happens in exhalation
In the bronchioles stretch receptor are stimulated by the inhalation of the lungs and they send inhibitory impulses back to the ventilation centre
This causes impulses to muscles to stop and they reflex enabling exhalation.
What is residual air
Air that hasn’t been expelled which mixes with inhaled air
How do you work out minute ventilation
Tidal volume *number of breathes
In fight or flight what happens when are stretch receptors are stimulated
Impulses are sent to the our cardio vascular centre
In fight or flight describe what happens when impulses are sent to the CV centre (stroke volume and venous return
It causes our heart rate to raise via the sympathetic nerve which leads to increased venous return and stroke volume
Cardiac output increases as a result of the raised heart rate and stroke volume which means oxygen is transported faster around the body
In fight or flight how is blood pressure prevented from exceeding a limit and explain what happens
By negative feedback,in this process nerve impulses are sent by pressure receptors in the aorta and carotid artery to the cv centre
It results in inhibitory nerve impuls s being sent from the Cv centre to the sinoatrial node
State the key component in the controlling of breathing rate and depth
The concentration of dissolved co2 in the blood
What happens when co2 dissolves in blood
The Carbonic acid dissociates into hydrogen and hydroencarbonate ions ph lowers
Describe how breathing rate and depth is controlled during exercise
Chemoreceptors are sensitive to hydrogen ions and they detect the rise in their concentration (they are located in the ventilation centre of the medulla oblongata)
Impulses are sent to other parts of the ventilation centre and then are sent from on the ventilation centre of which help in stimulating muscles that are involved in breathing
Explain how the carotid artery and Aorta are involved in controlling breathing rate and depth
In their walls they contain chemoreceptors and they are to stimulated by changes in ph
Impulses at sent to the ventilation centre
They have receptors that monitor blood
Describe how breathing is controlled in exercise
Impulses are sent from the motor cortex to the ventilation centre in the medulla oblongata which causes ventilation to increase
Stretch receptors in muscles and tendons also send impulses to the ventilation centre which also allows ventilation to increase (that are involved in movement
Chemoreceptors that are sensitive to co2 levels and to Change s in blood temperature increase the depth and rate of breathing via the ventilation centre
What are slow twitch fibres
These fibres are specialised for slowed,sustained contraction are to cope with long amounts of exercise
What are fast twitch fibres and where does the ATP used for them come from
These fibres are specialised to produce rapid intense contraction ATP is done made for anaerobic gylycoylsis
State the role of actin in the sliding filament theory
Contains myosin bond sites
State the role of myosin
Contains ADP and pi and attached to myosin sites on actin this releases ADP and Pi causing head to nod foward
State the role of troponin and tropmyosin
Both cover myosin bindings sites with troponin causing tropomyosin to move
State the role of calcium 2+ ions
They cause the movement of troponin and tropomyosin by binging to the troponin
State the role of ATP
Cause the separation of actin and myosin by binding to myosin
State the role of atpase
Hydrolysis ATP on the myosin to ADP and pi causing myosin head to change back to normal
When the muscle relaxs what happens in the sliding filament theory
It’s not stimulated by nerve impulses, ATP is used to actively pump out ca ions out of the muscle sacroplasm and troponin and trypomyosin move over blocking the myosin bindings sites
In aerobic respiration why aren’t glucose and oxygen brought together directly
It would result in a large release of energy that happens to quickly which could damage the cell
State where the electron transport chain is located in
Inner mitochondrial membrane
State where the H+ ions that are moved by the energy of the etc come from
The hydrogen ions came from the one released via glycolysis,Krebs cycle link reaction
Where is ATP synthase located
In the inner mitochondrial membrane
In The etc what is the very last step
H ions and electrons recombine to form hydrogen atoms and combine with oxygen to form water
What is the role of ATP synthase in oxidative phosphorylation
It’s the enzyme that catalyses the reaction between ADP and pi to produce ATP
What is end point inhibition
It’s how the rate of respiration is controlled
As ATP Inhibts an enzyme that’s responsible for the phosphorylation of glucose by doing so it means glycolysis can’t occur
State how lactate is formed in anaerobic respiration and why it’s formation enables a small amount of ATP to be produced
Pyruvate at the end of glycolysis is reduced by adding two hydrogens forming lactate
This oxidises the reduced Nad meaning it can carry more hydrogen ions so anaerobic respiration can continue
Why is oxygen uptake greater than normal in the recovery period
As more oxygen is needed to fuel the oxidation of lactate into pyruvate
Explain how creatine phosphate regenerates ATP
It’s hydrolysed and it provides energy along with a phosphate which combines with ADP forming ATP
What is the use of creatine phosphate to regenerate ATP known as
The ATP/PC system
State the 3 energy syttens in the body
ATP/PC system
Anaerobic respiration
Aerobic respiration
What happens in anaerobic respiration.
Pyruvate is reduced forming lacatate and glycolysis still occurs
When is the ATP/PC system used
During intense exercise and provide energy for 6-10 seconds ie sprinting/throwing
How is creatine phosphate regenerated
From ATP when the body is at rest
In anaerobic respiration how are the co enzymes nad reduced
They are used to reduce pyruvate into lactate
During intense exercise what would you expect to happen to cardiac output
It would increase because strike volume and heart rate would also as venous return to the heart is faster in which more blood can be expelled faster
State the role of the sinoatrial node and its location
It’s located in the wall of the right atrium beneath the superior vena cava
It’s where depolarisation first starts and it’s non as the pacemaker it sends electrical impulses to the AVN
What is the role of the AVN
It sends electrical impulses after a delay to the purknye fibres
State the role of the bundle of His
They are a collection of purkyne fibres together
State the role of the bundle of his and purkyne fibres
They carry electrical impulses into the ventricles as they have smaller branches that spread into each ventricle this causes the cells in the ventricles to contract as they are depolarised and this continues upwards towards the atria
During excerise how is blood pressure prevented from rising too far
Pressure receptors in the aorta and in the carotid artery send nerve impulses back to the cardiovascular control centre
The CCC sends inhibitory nerve impulses from here to the sinoatrial node
What is this process known in the lowering of blood pressure
It’s called negative feedback
State how the cardiovascular centre increases heart rate in fight or flight and state what impact it has blood distribution
It’s sent impulses by stretch receptors in the muscles and tendons this causes heart rate to raise via the sympathetic nerve which increases venous return which leads to rise in stroke volume this in turn increases cardiac output meaning oxygen and fuel is transported around the body faster
What is homeostasis
It’s the maintaince of a stable internal environment
What is meant by negative feedback
A mechanism that restores the levels of substances in the body back to normal
Ie blood pressure
What is meant by positive feedback
This system results in the amplification of the change so it exceeds normal levels
Describe how negative feedback works
Receptors in the body detect a deviation from the norm
They are connected to the control centre which communicates to effectors
Which counteract and bring levels back to normal
In negative feed back give examples of effects
Muscles
Glands
How does negative feedback work in terms of ranges
It works within very narrow limits
Give examples of negative feedback in the body
Glycolysis
Controlling blood pressure
Core body temperature
Give examples of positive feedback in the body
Blood clotting
Atherosclerosis
What is thermoregulation and state what normal core body temperature is
Its the control of the body temperature
37.5wwe
What detects changes in blood temperature and where are they located
Receptors and they are found in the hypothalamus
What is the role of theromreceptors
They are on the skin and they detect temperature changes and they send impulses to the hypothalamus
When our core body temperature is too high state changes in our body that occur and state what causes these changes to happen
The high temperature is detected by thermoreceptors and they send impulses to the hypothalamus
They cause the sweat glands to secrete sweat which evaporates which take heat energy from the skin
Vasodilation of the arterioles which means they become wider and relax and more blood flows closer to the skin and energy is lost by this (shunt vessel contricts)
In colder climates state the way the body keeps core body temperature constant
Skeletal muscles shiver which helps to increase body temperature
Vasoconstriction- the arterioles constrict which reduces blood supply to the surface capillaries meaning we lose less energy
Hair contract- this traps layers of air which insulated the body
What are the 4 ways of energy
Conduction-this involved direct contact with an object resulting in enegry transfer ie pouring water
Convection-the bulk movement of air as it heats and explants
Radiation -when we warm the environments
Evaporation
During exercise our core body temperature increases state the processes that go in our body that lower body temperature
Evaporation of sweat from surfaces of lungs and of skin help in increasing enegry loss
Arteriole vasodilation which increases enegry loss by conduction,convection,radiation
What is chemiosmosis
The movement of H+ ions across a memebrane generating ATP
What type of lymphocyte is moderate exercise believed to enhance
Natural t killer cells
How do natural killer cells work
They provide non specific immunity
They release a protein called perforin which makes pores in the targeted cell membrane which later leads to cell apoptosis
Why is doing vigorous exercise an issue at times
It’s beloved to suppress the immune system with
Natural killer cells,phagocytes,B cells and t helper cells being suppressed in
How does the antibody production fall with very vigorous exercise
The decrease in T helper cells reduces the amount of cytokines that’s available to activate lymphocytes
What was the issue with using previous technology for treating damaged joints
Lots of pain
Prolonged recovery
Increased chance of infection
Large incision
Describe ways that damage can occur on joints
Ligaments can be damaged by sudden twisting/abrupt movements
Cartilage that covers surfaces of bones may wear away causing bones to grind onto each other
What is keyhole surgery
When small incision are made in the joint and optical fibres are used to repair the joint
Give reasons as to why keyhole surgery is more effective
Recovery after keyhole surgery is faster
Less bleeding
Less recovery time
Shorter hospital stay
What are prosthesis
It’s when an artificial body part is used by someone with a disability enabling them to regain a degree of normal function
What problems can occur with doing to little excerise
Higher blood pressure leads to CDHD
Gain weight
Increased ldls
Increase cancer risk
Reduced bone density
Lowered natural killer cells
State the benefits of prosthesis
They allow people to carry on playing sports
They can replace whole limbs
State benefits of doing moderate exercise
Lower blood pressure
Increased HDl
Maintain weight
Reduced cancer risk
Increased bone density
More increased natural killer cells
State disadvantages of doing to much exercise
Poor athletic performance
Chronic fatigue
Increased infections
Increased joint damage
What are hormones
They are chemical messengers that are released directly into the blood from endocrine glands
Describe how hormones work
They enter target cells or bind to complementary receptor molecules that can be found on the outside of cell membranes
Give the two types of hormone
Peptide hormone
Steroid hormone
State why peptide hormones can’t pass through the cell membranes
As they are charged
What are peptide hormones and how do they work
They are protein chains
They bind to a receptor on the cell membrane which activates a second messenger in the cytoplasm
The second messenger is responsible for bringing about chemical changes within the cell because it affects gene transcription
What are steroid hormones and how do they work
They are formed from lipids and they bind directly a receptor molecule within the cytoplasm
Once activated the hormone receptor complex functions as a transcription factor as it switches enzymes on or off
What is meant by hormone-receptor acting as a transcription factor
They switch enzyme synthesis on or off
What is transcription imitated by
An enzyme called RNA polyermerase and transcription factors along with regulator proteins binding to DNA
In transcription what is the name given to the region that transcription factors bind to
Promoter region
How do inactive transcription factors become active
By the action of hormones
Either by activating second messengers
Or by binding with receptors to become transcription factors
Give ways in which transcprition can be prevented
By protein repressor molecules attaching to DNA on the promoter region
Or by them binding to transcription factors
Name 3 hormones that enhance performance
EPo
Creatine
Testosterone
What are performance enhancing drug
And give some example
They are drugs that enhance and better people’s performance
EPo
Creatine
Testosterone
What is EPO and state where it’s produced and it’s function
A peptide hormone produced in the kidneys
It’s stimulates the formation of new red blood cells in the bone marrow benefitcal for endurance runners
Give health risks of EPo
Blood clots
Risk of thrombosis
Stroke
Heart attack
What is testosterone and state it’s function
It’s a steroid hormone
It’s responsible for the development of male characteristics
Why have anabolic steroids been developed to be used instead of testosterone
As testosterone breaks down to quickly
Give the side effects of anabolic steroids
Aggression Liver damage Heart disease Low sperm count High blood pressure
What is creatine used for and where can it be found
It’s found in fish and meant and it’s benefitcal
,it’s stored in muscles for high intensity sport
State side effects with creatine
Vomiting High blood pressure Nausea Muscle cramps Kidney damage
What are the axis on a ecg
Electrical activity on y
X-time
