﻿Hi everyone, Miss Strmec here. Welcome back to another lesson of unit four, bioenergetics. Today, we're going to be having a look at respiration. For this lesson, you will need a pen and a piece of paper. Feel free to pause the video here and collect your equipment, if you don't have it already. Now take a moment to make sure that you're in a distraction free environment, and that your phone is on silent. When you're ready, let's begin. In today's lesson, we're going to be looking at three main areas. I'm going to introduce you to the concept of respiration. We're going to look at the definition and the equation. Then we'll look at what our body actually uses the energy that's released for. Finally, we'll have a look at what effect exercise has on the respiration system. First, let's have a look at respiration. Aspiration is an exothermic reaction, which releases energy to allow ourselves to carry out vital functions. Respiration is the release of energy and all cells need respiration to survive. Human respiration comes in two forms, it can either be aerobic, meaning it requires oxygen or anaerobic, meaning it happens without oxygen. But for today, we're going to be focusing on aerobic, which is with oxygen. Next lesson, we will visit anaerobic, which is without. Aerobic respiration has a very similar equation to photosynthesis. You'll notice that it's actually just the reverse. So the reactants in aerobic respiration are glucose and oxygen. The products are carbon dioxide and water. This should look familiar because in photosynthesis, our reactants are carbon dioxide and water, and the products are glucose and oxygen. If you can remember that it's a simple reverse, it will make memorising the equation much easier. Now just like photosynthesis, we also need to know the symbol equation. So have a think now and see if you can recall what the symbol for glucose is. Next, have a think about what the symbol for oxygen is, then carbon dioxide and water. Let's see if you got it correct. The symbol equation for glucose is C6, H12, O6. The second reactant is oxygen, which is symbol is O2. The products of this equation are water, which is H2O and carbon dioxide, which is CO2. Just like all chemical reactions, this requires balancing. You should remember balancing from the photosynthesis equation. Remember when we balance an equation, we're attempting to make the atoms on the reactant side of the equation, equal to the atoms on the products side. So in order to balance the respiration equation, we are going to need six molecules of oxygen, six molecules of water and six molecules of CO2. Let's do a quick quiz and see what you can recall. I'll give you five seconds to read the question and then the answer will appear on screen. Shout it out when you think you've got it right. Three, two, one. If you said glucose and oxygen, you're correct. Next question. Three, two, one. If you said the first missing part is oxygen, well done, you got it correct. If you said the second missing part was carbon dioxide, great work. Next question. Three, two, one. If you said true, you're correct. Aerobic respiration does require oxygen. Great work. Now I'd like you to have a go at some independent practise. I've listed a word bank below that you can use to fill in the blanks. Pause your screen here. Complete the work on your piece of paper and resume when ready. Now let's have a look at the answers. The answers are now onscreen. Aerobic respiration is the release of energy from the food you've eaten. Like burning, it requires oxygen and produces carbon dioxide and water as waste products. If you need to, pause your screen here to make sure your answers are correct. Next, we're going to have a look at how the energy that is released during respiration is used within your body. The first use is for muscle contraction, both your internal organs and your skeletal muscles rely on the energy from respiration in order to contract. The second use of energy is in maintaining an optimal body temperature. This is important in order for all of the reactions in your body to carry out as normal. It is particularly important for males and births. Third is building up of large molecules from smaller molecules. This includes glucose being converted into glycogen for the storage of energy in your liver and your muscles. In plants, this looks a little bit different. The building up of complex sugars is what energy is used for in plants. So converting glucose into starch as an energy storage in the leaves, the stem and the roots. Next, let's have a look at the body's role in respiration. We'll start by looking at the blood, which is known as the body's delivery system. This is because the blood carries the reactants that are needed in for respiration. And it also removes the waste products that are produced when respiration is over. Second is the heart. The heart pumps the blood to all of the cells. It's important that the heart rate can keep up with the demand for respiration. Third is breathing. The breathing is important because it maintains the concentration gradient, so that the diffusion of gases can carry out smoothly. You should recall from organisation that oxygen and carbon dioxide are exchanged at the alveoli. Four is digestion. The digestive system is important because it converts the food that we eat into molecules that our body can use. Most of the food we eat contains glucose, and it's broken down by amylase in our small intestine. Once it's small enough, glucose is able to diffuse into the blood in order to be transported to the cells that are respiring. Finally, glycogen. We spoke earlier about how glycogen is a storage of glucose in the muscles and the liver. When needed glycogen converts back into glucose, in order to be used for respiration. Let's do a few quick questions to see what you can remember. You have five seconds to read the question on screen and point to the answer that you think is correct. Three, two, one. If you said muscle contraction, that's correct. Excellent work. Next question. Three, two, one. If you said building up larger molecules, you're correct. Well done. Third question. Three, two, one. If you said option four, building up sugars, well done, you're correct. Final question. Three, two, one. If you've pointed to option two, maintaining body temperature, excellent job. Now let's have a look at how respiration is affected by exercise. When exercise begins, the body needs more energy to be released. If more energy is needed, then we need to increase the rate of respiration. In order for respiration to increase, the removal of waste products like carbon dioxide and water will also need to increase. Let's do a quick question to see what you can remember from that slide. Five seconds. Shout out the answer. Three, two, one. If you said increases, that's correct. Excellent work. Now let's have a look at how the body changes during exercise. The heart rate will need to increase. This happens so that we can pump blood to the muscles faster. The faster the blood gets there, the more glucose and oxygen available. Next, the volume of blood pumped in each heartbeat also needs to increase. We need to pump more blood per beat. Again, the more blood that can get to the muscles, the more oxygen and glucose available. Thirdly, we're going to look at breathing rate. The breathing rate also increases. The faster the intake of air, the faster the oxygen can circulate around the body. We also need the excretion of carbon dioxide to happen quicker, and that will happen with each exhalation. Fourth, we're going to look at the depth of breathing or the volume of air in each breath. This is also going to increase. This means that we get more air with each breath, more oxygen, therefore, can go through the body. And finally, the glycogen levels in the muscles are going to decrease. This is because glycogen is going to be broken down into glucose, that's going to be used in the respiration process. I'd now like you to have a go at some independent practise. The table on screen summarises the changes that our body makes when we start exercise. There are lists of words above that you can use to fill in the blanks and they may be used more than once. Pause your screen here and resume when you're ready. Now let's have a look at the answers. The answers are now onscreen. Pause here to mark and feedback your own answers. Now let's do some quick recall questions. You have five seconds to shout out the answer to the question that's on screen. Three, two, one. If you said that the heart rate increases, excellent, that's correct. Next question. Three, two, one. If you've said increases, great work. That's correct. Next question. Three, two, one. If you remembered that that was decreases, excellent work, that's correct. I'd now like you to do another independent practise. For this one, I'd like you to draw a line to match the condition with the change. Pause your screen here and resume when you've completed it. Let's see how you did. For increased heart rate, the change was that the blood is being pumped faster. For increased breathing rate, the change was that the intake of oxygen is faster. For increased breathing depth, the change was that there was more air in every breath. For increased blood volume, the change was that there was more blood in each pump. For decrease in glycogen levels, the change is that there's more glucose ready for respiration. Pause your screen here, if you need a moment to mark and feedback, your own answers. Great work. Great work, everyone. You've made it to the end of the video portion of this lesson. You should now know that the respiration equation is glucose plus oxygen equals carbon dioxide and water. You should be able to identify that the respiration equation is a release of oxygen and an exothermic reaction. You should be able to identify the uses of energy, which include muscle contractions, maintaining body temperature, building large molecules from small molecules, and in plants, it's used to build complex sugars like starch. You should be able to understand how the body is affected by exercise and how it meets the demand of needing more energy by increasing the rate of respiration. Don't forget to hit next to complete the final quiz. Next lesson we're going to be looking at anaerobic respiration, which is respiration that occurs without oxygen. Excellent work today. See you next lesson.

In this lesson we will learn the definition of respiration and its importance in the body. We will look at how the body changes during exercise and why these changes are necessary.

Combined Science

Y10 Combined Science (Foundation)

Key Stage 4

Year 10

Miss

Respiration

Bioenergetics (FT)

UNIT

Photosynthesis

Photosynthesis required practical

Photosynthesis required practical results

Limiting factors of photosynthesis

Review photosynthesis

Anaerobic respiration

Metabolism

Synoptic links

End of topic review


Exam Skills

Maths Skills

Scientist case study-Ynes Mexia

Biology

Y10 Biology

Bioenergetics

Manipulating factors of photosynthesis HT

Consequences of anaerobic respiration

Y10 Combined Science (Higher)

Bioenergetics (HT)

Lesson overview: Respiration

Video

Presentation

Worksheet

Exit Quiz

Transcript

13 lessons in Bioenergetics (FT):

15 lessons in Bioenergetics:

15 lessons in Bioenergetics (HT):