Module 09 - Tissue Differences energy metoablism and enzymes. Flashcards
_____ allows study of muscle fibres and the effects of acute exercise and exercise training on fibre composition
muscle biopsy
Dark fibres in microscopic slide are the ____ ___ fibres
slow twitch fibres (red)
Medium coloured fibres under microscope are ____ ____ fibres
Intermediate fibres
Lightest coloured fibres under microscope are ____ __ fibres
fast twitch fibres
Fibre hypertrophy
Individual fibres increase in their diameter
Is myosin structural and functional?
Yes
What are the two major subtypes of Myosin?
Heavy myosin & light myosin
Slow Twitch (Type I) fibres have (low/high) relative ATPase activity
Low
Slow Twitch (Type I) fibres have (Slow/fast) relative ATPase Max contraction velocity ?
Slow
Slow Twitch (Type I) fibres have (low/high) ATP used/force developed?
High
Fast Twitch (Type IIA) fibres have (low/high) relative ATPase activity ?
High
Fast Twitch (Type IIA) fibres have (Slow/fast) relative Max contraction velocity ?
Fast
Fast Twitch (Type IIA) fibres have (low/high) ATP used/Force developed?
Low
Fast Twitch (Type IIB) fibres have (low/high) relative ATPase activity ?
High
Fast Twitch (Type IIB) fibres have (slow/fast) relative Max contraction velocity?
Fast
Fast Twitch (Type IIB) fibres have (low/high) ATP used/force developed ?
Low
Slow Twitch Fibres (type I) have what dominating energy pathway?
Oxidative
Fast Twitch Fibres (type II) have what dominating energy pathway?
Oxidative glycolytic
Fast Twitch Fatigue-able (Type IIB) have what dominating energy pathway ?
- ATP/CP
- Anaerobic Glycolysis (glycolytic)
What fibres are active in both low and high intensity exercise?
Slow twitch fibres (endurance fibres - always working)
What fibres are only active in intense activity?
Fast Twitch fibres
Slow Twitch Fibres (type I) have ____ aerobic (oxidative) capacity and fatigue resistance
High
Slow Twitch Fibres (type I) have ___ anaerobic (glycolytic) capacity and motor unit strength
Low
Slow Twitch Fibres (type I) have ____ contractile speed and Myosin ATPase
Slow (110 ms to reach peak tension)
Slow Twitch Fibres (type I) have ______ fibres per motor neuron
10-180
Fast Twitch Fibres (Type IIA) have _____ aerobic (oxidative) capacity and fatigue resistance
moderate
Fast Twitch Fibres (Type IIA) have ___ anaerobic (glycolytic) capacity and motor unit strength
High
Fast Twitch Fibres (Type IIA) have ____ contractile speed and myosin ATPase
Fast
Fast Twitch Fibres (Type IIA) have _____ fibres per motor neuron
300-800
Fast Twitch Fibres (Type IIB) have _____ aerobic (oxidative) capacity and fatigue resistance
Low
Fast Twitch Fibres (Type IIB)
have ____ anaerobic (glycolytic) capacity and motor unit strength
High
Fast Twitch Fibres (Type IIB) have ____ contractile speed and myosin ATPase
fast
Determinants of fibre types (3)
- Genetics
- exercise training & inactivity
- Ageing
Creatine Kinase is of what energy system?
Phosphate energy system
microcompartimentisation of CK isozymes allows 2 factors
- Allows high [ATP/ADP] ratios where ATPases are found (muscle myosin)
- Allows low [ATP}/[ADP] in mitochondrial matrix to stimulate oxidative phosphorylation
What are the two types of creatine kinase subunits possibly in the cytosol
- B (brain)
- M (muscle)
(mixing can make 3-> CK-MM, CK-BB, CK-MB)
What is the main form of isozyme in the brain and smooth muscle?
CK-BB
Skeletal muscle is 99% _____ isozyme
CK-MM
Myocardium is 70% ____ isozyme
CK-MB
Sarcomeric (sMtCK) mitochondrial CK is in _____ muscle
Striated (skeletal)
Ubiquitous MtCK is in ____
Most tissues except skeletal muscle (brain, kidney, sperm)
All 4 Hexokinase reactions catalyse ____
Hexose
Hexokinase I-III are important in the ___
Brain
Hexokinase IV is also called ______
Glucokinase
Hexokinase IV (Glucokinase) has a very important role in ______ metabolism
Carbohydrate
Hexokinase IV (Glucokinase) is NOT inhibited by its product, ______
glucose-6-phosphate
Hexokinase IV (Glucokinase) are found where [glucose] levels are ____
High (liver, pancreas)
Hexokinase IV (Glucokinase) can ONLY phosphorylate glucose if the concentration of this substrate is ____
High
Are hexokinase I-III inhibited by their product?
Yes
Which Hexokinase enzyme is the most prominent in all mammalian tissues?
Hexokinase I/A
What Hexokinase enzyme is found in the muscle and heart?
Hexokinase II/B
Where is Hexokinase II/B loacted?
In mitochondria (direct access to ATP)
Which Hexokinase enzyme is only active when glusoce concentrations are really low?
Hexokinase III/C