In order for respiration to take place air must be taken in. Name two of the air passages which allow air to enter the body. 1. 2. (2) Describe what gaseous exchange is and clearly state where it takes place. (3) (Total 5 marks) Explain how diffusion takes place in the alveoli. (4)
(i) Award one mark for each of the correctly named air passages mouth nose pharynx epiglottis larynx trachea bronchi bronchioles (ii) Award up to three marks for a correct answer. award up to two marks for correctly describing it as the oxygen being taken in / being exchanged for the carbon dioxide which is to be breathed out award one mark for stating that gaseous exchange occurs in the lungs / alveoli
Applied Anatomy and Physiology The cardio-respiratory system Blood Vessels
To describe the characteristics of the various blood vessels in the body. To apply their structure to their function within the circulatory system. To assess how arteries redistribute blood during exercise.
Blood Vessels Arteries Veins Capillaries On average we have 100,000 miles of blood vessels in our adult bodies. Carry about 8 pints of blood around the body.
Blood Vessels- Arteries Arteries carry oxygenated blood Away from the left side of the heart. High pressure to push the blood around the body. Stretch and flex as the blood surges through them. Arteries = Away from the heart.
Blood Vessels- Arteries
Blood Vessels- Veins Veins carry de-oxygenated blood towards the heart. Low pressure as the blood returns to the heart Veins = Carry blood into the Heart. Not elastic and have no stretch. Have valves to prevent backflow of blood.
Blood Vessels- Veins
Blood Vessels- Capillaries Huge network of tiny vessels. Link Arteries and Veins. Very narrow only allowing 1 red blood cell at a time. Thin walls to allow rapid and effective diffusion.
Blood Vessels- Capillaries
Blood Vessels High pressure- Thick, elastic walls. Pulsate to surge blood around body. Small lumen Oxygenated blood 1 cell thick. Tiny lumen to allow 1 red blood cell. Oxygenated and deoxygenated blood. Lower pressure- Thinner walls. Non elastic. Valves to prevent backflow. Deoxygenated blood.
Exam Question Describe the main characteristics of the 3 types of blood vessel. The main characteristics of arteries are. The main characteristics of veins are. The main characteristics of capillaries are..
Redistribution of Blood during exercise During exercise where does the blood flow need to be concentrated?
Redistribution of Blood during exercise
Redistribution of Blood during exercise During exercise where does the blood flow need to be concentrated? Greater demand for oxygen from voluntary muscles Greater demand to get rid of CO2 from voluntary muscles Increased flow to voluntary muscles
The Vascular Shunt Vascular- Vessels This refers to the redistribution of blood during and after exercise. At rest blood is concentrated towards the vital organs. Blood is diverted to the working muscles during exercise.
Vasodilation and Vasoconstriction Arteries have thick muscular walls which are able to constrict and relax. This opens or closes the lumen (inner hole ) and restricts or allows blood flow.
Vasoconstriction Vasoconstriction Closing of the lumen restricting blood flow.
Vasodilation Vasodilation Opening of the lumen allowing increased blood flow.
Discussion Questions Why do we go red after exercise? When it is cold what happens to your fingers and toes? What is the difference between these two images? Why do athletes not eat less than 2 hours before an event?