Download Physiology KNPE 125 Exam Review: Muscle Contraction, Energy Systems, and Digestion and more Exams Health sciences in PDF only on Docsity!
PHYSIOLOGY KNPE 125 EXAM WITH COMPLETE SOLUTIONS!!
Sensory Root Afferent neurons enter the spinal cord
Interneurons
- Processing centre of the spinal cord
- Process afferent signals
Anterior Motor Neurons and Motor Root Exit of efferent neurons from the spinal cord
Path of the spinal cord reflex
- Afferent neuron enters via sensory root
- Synapses with interneurons
- Interneurons activate/inactivate efferent neurons
- Efferent signal exits via motor root
3 Spinal cord reflexes
- flexor reflex
- Muscle stretch reflex
- Golgi Tendon Reflex
Flexor Reflex
- The quick contraction of flexor muscles resulting in the withdrawal of a limb from an injurious stimulus.
- Afferent neurons synapses to interneurons and sends a signal via motor root
Muscle stretch reflex Knee jerk reflex. Causes stretched. muscle to contract (quads) and antagonist muscle to relax (hams). A stroke can cause spastic movements and loss of function
Golgi tendon reflex Prevents damaging force to tendons by sensing change in muscle tension.
Life span length of a persons life
Health span how long we stay in good health from brith to death
Types of contractions concentric (shortening), eccentric (elongating), isometric (not moving)
Length-tension relationship optimal length of a muscle for generating most power where there are most interactions of myosin and actin fibres
Other other size principle maximal force is the amount of muscle/contractile units active. Bigger muscle = more force
Endergonic reactions Mechanisms that require energy input.
- mechanical work
- chemical work
- transport work
How do muscles relax Ca2+ is removed from cytosol back to the SR by active transport via SERCA
3 importance things for performance and health strength, fatigue resistance, insulin sensitivity
3 aspects of strength Type 2 fibres, big muscles, high anaerobic capacity
sarcopenia the loss of muscle mass, strength, and function that comes with aging (fewer actin, myosin and sarcomeres)
2 things that maintain healthy aging
- Nutrition and especially protein as it stimulates muscle protein synthesis
- exercise helps increase type 2 fibres
Resistance training increase type 2 a and x fibres (bigger muscles). reduce effects of aging. increases proportion of less fatiguable fibres
anaerobic capacity Strengths and speed required for large amount of ATP periods in the absence of oxygen (lactic acid fermentation inhibits ability to produce force). fast supply.
PCr system a single phosphate transfer from PCr to ADP to make ATP. Very limited fuel source for short intense exercise
glycolysis the breakdown of glucose by enzymes, releasing energy and pyruvic acid. transported into muscle from the blood. type 2a can do this fast. 2 ATP from glucose and 3 from glycogen. strong muscles generate ATP faster
aerobic metabolism Metabolism that can proceed only in the presence of oxygen which has a long time supply
ATP synthase Large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP. NADH = 2.5 ATP, FADH2 = 1.5 ATP
beta oxidation of fatty acids produce acetyl CoA by breaking carbon bonds. Each turn produces 1 acetyl CoA, 1 NADH, 1 FADH2.
3 Substrates required for ATP production Glucose, FFA, Protein
4 systems that support system for energy GI tract (Exogenous), Liver (Endogenous), Adipose Tissue (Endogenous), Endocrine system
2 major functions of digestive system digest food and absorb nutrients
Digestion food is broken down into single modules that can be absorbed into blood. starts in mouth. chewing increases surface area so enzymes can breakdown food.
stomach
stores food and mixes with gastric juices to form chyme. controls rate of chyme emptying into duodenum.
gastric glands secrete acid into stomach. they have many folds to increase SA to better the job of breaking down food
pancreas secretes digestive enzymes into small intestine that help break down protein, carbs and fats into simple forms
liver and gallbladder liver filters the blood and produces bile that is stored In the gallbladder. assists in absorption of fat and excrete waste from blood.
peristalsis Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system. contraction of smooth muscle that break down food.
Reverse paristalsis vomiting
6 steps of digestion
2 purposes of transport of Na+
- Na+ gradient can be utilized for secondary active transport
- Generates osmotic gradient (water flows where there is most Na+)
Absorptive (post-prandial) state lasts 3-4 hours post meal where nurturing are being absorbed and blood glucose increases. fatty acid and glucose are being stored. insulin increases. Spike = glucose incursion
post-absorptive state time between meals where nutrients are not being absorbed and the body metabolizes more FFA and ATP. Fatty acids and glucose are mobilized from storage. insulin decreases and glycogen increases
alpha cells glucagon.
beta cells insulin. These cells are attacked in type 1 diabetes.
insulin increases outflow of glucose and FFA to decreases blood glucose levels. inhibits glucose production in the liver and FFA release from adipose tissues
glucagon increase inflow of glucose and FFA to increases blood glucose levels
insulin dependent glucose uptake in muscle insulin activate conversion of glucose to glycogen and activates carbohydrate metabolism.
insulin independent glucose uptake in muscle when working out, AMPK activate conversion of glucose to glycogen and activates carbohydrate metabolism.
skeletal muscle fatty acid uptake insulin or AMPK covert fat from adipose tissue into TAG lipid droplets
adipose tissue very simple cells that are made up of 80-95% triglycerides that main function is to store and mobilize fat
fatty acid mobilization lipases breakdown the lipid droplets into FFA which enter the blood
- fuel mobilization
- gluconeogenesis -glycogenolysis -lipolysis
Glycogenolysis breakdown of glycogen to glucose
Gluconeogenesis formation of glucose from noncarbohydrate sources. reverse glycolysis. pyruvate, lactic acid, amino acids, glycerol
de novo lipid synthesis formation of lipids from carbohydrates. Liver processes glucose with enzymes to form FFA. FAA is transported to adipose tissue and stored
Effects of insulin in the liver increases glucose uptake, activates glycogen synthesis, activates fatty acid synthesis
insulin sensitive muscle decreases with inactivity and age. increase in muscle fat
insulin insensitivity (insulin resistance): cells become less responsive to insulin. due to increase FFA uptake into other tissues (liver + adipose tissue)
hyperglycaemia high blood glucose concentration (chronic)
Glycosylation can contribute to atherosclerosis. blood flow complications
3 primary ATPase that consume ATP during muscle contraction Myosin, SERCA, Na/K pump
Vicious cycle decrease insulin sensitivity in muscle, liver, and adipose tissue leads to an increase in insulin to restore resting blood glucose that leads to increase FFA storage in muscle, liver, and adipose tissue which then leads to the beginning of the cycle and so on.
Negative feedback
- Sensor constantly monitors the regulated mass
- Acts to oppose or reduce the change in the regulated mass
