B2 Topic 3 Starter: Stick in the heart diagram -The structure of the Heart -Blood -The Circulatory System - Aerobic and Anaerobic Respiration Starter: Stick in the heart diagram On the next page there is a blank diagram to copy and give to students. The information has been done on a slighter less complicated diagram to help students visualise the parts. On the higher paper, the more complicated diagram is often shown.

Structure of the Heart Questions in the past have asked: -Label the structure in the heart -Describe how blood travels through the heart - Where the blood flows into and out of the heart

Structure of the Heart

Right= Blood without oxygen Left= Blood with oxygen (deoxygenated) Left= Blood with oxygen (oxygenated)

Where does blood enter the heart? NEED TO KNOW: Both are Veins Past paper question NEED TO KNOW: Both are Veins

How does blood flow through the heart? Step 1: Enters the atrium Past paper question 1 1 Step 1: Enters the atrium

How does blood flow through the heart? Step 2: Pumped into ventricles Past paper question 2 2 Step 2: Pumped into ventricles

Step 3: Pumped out of ventricles How does blood flow through the heart? 3 3 Past paper question Step 3: Pumped out of ventricles

Which blood vessels transport blood away from the heart? To lungs To rest of body Past paper question Both are arteries

Valves stop blood flowing backwards What stops blood flowing backwards in the heart? Past paper question Valves stop blood flowing backwards

Why is the heart called a double pump? Heart pumps blood to two places; left side pumps blood to the rest of the body and right side pumps blood to the lungs

Why do the ventricle walls have different thicknesses? Left ventricle has a thicker wall = Stronger so can pump blood further round the body (Blood under higher pressure)

Now lets have a look at an exam question about this..........

The diagram shows a human heart.       (i) Draw an arrow onto the diagram to show where oxygenated blood enters the heart.(1)     (ii) Suggest how the blood flowing through the pulmonary artery would be different from the blood flowing through the aorta.(2)  (iii) Describe the role of the valve labelled on the diagram.(2)    

Answer Acceptable answers Mark (i)   Answer Acceptable answers Mark (i) ignore any labels on the arrow   allow an arrow coming out of the opening of pulmonary vein into heart (1) (ii) Any two from the following: · (blood in pulmonary artery) deoxygenated (1) · (blood in pulmonary artery) lower pressure (1) accept reverse argument for aorta carrying less oxygen / no oxygen less force / slower   (2) (iii) Any two from the following: · prevent backflow (1) · (from ventricle) into atrium (1)    description of backflow ignore references to left atrium and deoxygenated blood (2)   I have copied the heart answer onto another slide just in case it doesn’t project big enough.

Components- What something is made up of, i.e. the components of blood Why do we have a heart? To transport gases, glucose, nutrients and water around the body. These are carried by the blood. Key words: Components- What something is made up of, i.e. the components of blood

What are the components of blood? May want to print this out and get students to label them with information you give. What do they do?

Clot the blood Carry Oxygen Plasma - Liquid to carry the substances Answer is always: DESTROY PATHOGENS Carry Oxygen May want to print this out and get students to label them with information you give. Plasma - Liquid to carry the substances

The photograph shows a blood smear from a healthy person. (i)   Name the two types of blood cells, X and Y, shown in the photograph. (2) .................................................................................................................................................................................................................................. Name the liquid part of the blood. (1)       ..............................................................................................................................................

Question Number Answer Acceptable answers Mark •   X - white blood cell / phagocyte (1) •   Y - red blood cell / erythrocyte (1)   (2) Question Number Answer Acceptable answers Mark plasma   (1)

Why does the blood transport substances around the body? Respiration Blood transports oxygen and glucose to cells so they can make energy in respiration. Blood transports carbon dioxide and waste away from cells.

Respiration Exam questions about respiration could ask you to recall parts of either equation. It could also ask you to name the type of respiration based on the products. It could also ask you to compare the effects on breathing/heart rate before and after exercise and why this is important to respiration. We will look at the equations next and some exam questions.

At the cells Aerobic Respiration = Lots of oxygen available Come from blood Anaerobic Respiration = No oxygen

Exam questions on this topic often involve graphs. What does it mean? More exercise More oxygen needed by the cells for respiration Heart rate and breathing rate will increase

Now lets have a look at an exam question about this..........

Had to print screen this as it wouldn’t copy properly Had to print screen this as it wouldn’t copy properly. Rest of question is on next slide.

before exercise (pulse rate in beats per minute) swimming cycling sprinting 69 73 after exercise (pulse rate in beats per minute) 98 110 149 (b) Pearl measures her heart rate during three different types of exercise. Explain why the exercises have different effects on her pulse rate. (3)

Question number Answer Mark (a)(i) C (1) (b) an explanation linking the following: (idea that) the higher the impact of the exercise the higher the pulse rate (1) (idea that) higher pulse rate means the heart is beating faster (1) (idea that) because there is an increased energy demand (from aerobic respiration) for the high impact sport (1) (3)

Cardiac output Many exam questions in the past have asked you to use the cardiac output equation sometimes linked to reading information from a table. Sometimes they will give you the equation, but more often than not they don’t so you will need to learn it. cardiac output = heart rate × stroke volume

Now lets have a look at an exam question about this..........

athlete stroke volume / dm3 heart rate / beats per minute cardiac output / dm3 min–1 at rest 0.1 53 5.3 during exercise   182 30.4 The volume of blood that the heart pumps with every beat is known as the stroke volume. Stroke volume can be used to indicate fitness level. The table gives information about the stroke volume, heart rate and cardiac output of an athlete at rest and during exercise. (a) Calculate the stroke volume of the athlete during exercise. (2)   answer = . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dm3 (b) Explain why it is important that the cardiac output of the athlete increases during exercise. (3).

  Answer Acceptable answers Mark (a) · evaluation (1)         30.4 ÷ 182 · Correct answer (1)         0.167 / 0.17 / 0.2 (dm3) give full marks for bald correct answer, no working ecf allow correct answer with full number of decimal points 0.1670329 (2) (b) An explanation linking three of the following points: · muscles working harder / contract faster (1) · need more energy (1) · (aerobic) respiration (1) · more / enough / faster delivery oxygen (1) · more / enough / faster glucose (to muscles / body) (1) · more / faster removal of carbon dioxide (1)         Ignore references to anaerobic respiration (3)