Describe (P4) the role of energy in the body and explain (M1) the physiology of three named body system in relation to energy metabolism.

Unit 5 16/03/2009

BTEC National Diploma in Health and Social Care

Introduction

I will try to describe the role of energy in the body and explain the physiology of three names body system in relation to energy metabolism. I will try explain where energy comes from, how the body uses energy, how many calories do we need, what is metabolism/catabolism and anabolism and also I will try explain cellular respiration aerobic/anaerobic is.

Most of the processes taking place inside our cells need energy in order to happen. Depending on our age, weight, the activities we will need a certain amount of calories. If somebody run every morning, will require more energy and calories per day. If somebody are an athlete also will require more calories per day. If the person sit, and work on a computer all day then that person don’t need many calories per day. Energy is measured in kilojoules (kJ).

Energy can exist in many forms, but chemical energy is the most common. Heat, light, sound, electrical and nuclear are other forms of energy. Energy cannot be created or destroyed. It can be transformed from one from into another.

Our energy comes from the food what we eat. If we do not eat proper meals, we could easily get sick and starting to have all sorts of diseases. Most of the humans are meat eaters but some vegetarians. Everybody have different types of body systems but our body works the same. Meals that we eat are important for nutrients of our body metabolism, vitamins and energy. All the energy used by all organisms on Earth comes from the sun. We don’t use the energy from the sun directly, we needs plants to do that for us. Plants are able to absorb sunlight and use the light energy to make food molecules from carbon dioxide and water, in a process called ’photosynthesis’. When we eat plants, we digest the complex food molecules back into simpler ones.

The basal metabolic rate (BMI) is the base rate at which your body consumes calories for basic metabolic functions like maintaining internal temperature, repairing blood, powering muscles at rest, etc. in other words, it is the rate at which your body consumes calories when at rest.

Metabolism. The first most important thing is our body metabolism. If we are not getting the proper food. All food has many types of vitamins and meats we eat have a lot of energetic sources. If we do not eat the food properly, we are easy vulnerable to all sorts of sicknesses. Most of common sicknesses are the biggest problem of our society is eating disorders, which are on diet. Metabolism is the sum of all chemical reactions occurring in human physiology and these will involve using or releasing energy from chemical substances.

Catabolism is the breakdown of large molecules into small molecules. It’s opposite process in anabolism, the combination of small molecules into large molecules. These two cellular chemical reactions are together called metabolism. Cells use anabolic reactions to synthesize enzymes, hormones, sugars and others molecules needed to sustain them, grow and reproduce.

Cell respiration is the process by which food is broken down by the body’s cells to produce energy.

Anaerobic cellular respiration occurs in the cytoplasm when no oxygen is present for the cell to continue respiration after glycolysis. This stage does not need oxygen and occurs in ...

This is a preview of the whole essay

Cell respiration is the process by which food is broken down by the body’s cells to produce energy.

Anaerobic cellular respiration occurs in the cytoplasm when no oxygen is present for the cell to continue respiration after glycolysis. This stage does not need oxygen and occurs in the cell cytoplasm. The stage ends in the production of pyruvic acid.

Aerobic respiration in the presence of oxygen uses the end product of glycolysis in the cycle to produce much more energy. Aerobic respiration is characteristic of eukaryotic cells when they have sufficient oxygen and most of it takes place in the mitochondria.

Conclusion

Every living thing needs energy sources. In order to get the energy, we need to eat right and take whatever the vitamins and minerals foe motivation. However, if we take extra energy of food, this would be a problem of the other side of the issue. This will cause to obtain more fat cells that we don’t need if not reduced right by exercise.

The cardiovascular system comprises the heart and blood vessels that circulate blood through the body, bringing oxygen and nutrients to muscles and organs and then returning it to the heart to be pumped again.

Structure of the heart

The heart is a hollow organ with walls formed of three different layers.

The inner most is called the endocardium. This is a thin smooth layer of epithelial cells. The middle layer is called the myocardium. This contains cardiac muscle and is the thickest layer. The outer layer layer is called the epicardium, this is a thin membrane.

The pericardium is the thin membrane that surrounds the heart and the roots of the great blood vessels. Fibrous pericardium is connective tissue which is attached to the sternum and diaphragm. Parietal pericardium is connected to the fibrous pericardium. Visceral pericardium, also known as the epicardium is attached to the myocardium.

The heart is known as a double pump because each side of the heart works separately. The right side of the heart receives deoxygenated blood from the body and pumps it only to the lungs, so if has thinner walls than the left side. The left side receives oxygenated blood from the lungs and pumps it out round whole body, as it has thicker, more muscular walls.

Right atrium receives de - oxygenated blood from the body through the superior vena cava and inferior vena cava which carries blood from the head, chest and arms and the inferior vena cava, which carries blood from the trunk and legs.

Right ventricle. This has a thick wall of myocardium. The right ventrice receives de - oxygenated blood from the right atrium to the lungs via the left and right pulmonary arteries.

Left atrium it receives oxygenated blood from the pulmonary veins, and pumps it into the left ventricle.

Left ventricle is one of four chambers in the heart. It receives oxygenated blood from the left atrium via and pumps it into the aorta.

The rights atrioventricular valve. When the valve is open blood flows freely from the right atrium to the right ventricle. When the right ventricle contracts the valve closes and blood flows into the pulmonary arteries.

The left atrioventricular valve. When open it allows blood to flow from the left atrium to the right ventricle. The valve closes when the left ventricle contracts to prevent blood from flowing back into the left atrium.

The pulmonary valve is a condition in which the flow of blood from the heart (right ventricle) is blocked at the valve that separates the heart from the pulmonary artery.

The aortic valve. If the pressure in the left ventricle rises above the pressure in the aorta, the aortic valve opens, allowing to exit the left ventricle into the aorta.

The circulatory system

Main function is to get food and oxygen to every cell in the body. The right side heart pumps deoxygenated blood to the lungs to collect oxygen. Then the left side pumps this oxygenated blood around the body. Arteries carry blood away from the heart at high pressure. Normally, arteries carry oxygenated blood and veins carry deoxygenated blood. The arteries eventually split off into thousands of tiny capillaries which take blood to every cell in the body. The veins then collect the used blood and carry it back to the heart at low pressure to pump round again. The coronary vessels also take oxygen and glucose back to the heart.

Arteries carry blood under pressure

Arteries carry oxygenated blood away from the heart. It comes out of the heart at high pressure, so the artery walls have to be strong and elastic.

Tunica adventitia consists of fibrous connective tissue.

Tunica media consists of smooth muscle and elastic tissue.

Tunica intima consists of flat epithelial cells to ensure the artery lining is smooth and does not impede the flow of blood.

Capillaries

Capillaries deliver food and oxygen direct to the body tissues and take waste products away. Their walls are usually only one cell tick to make it easy for stuff to pass in and out of them.

Veins take blood back to the heart

Veins carry deoxygenated blood back to the heart. The blood is at lower pressure in the veins so the walls do not need to be a thick. They have a bigger lumen than arteries to help blood flow. They have also have valves to keep the blood flowing in the right direction.

Blood

Blood’s more complicated than it looks, unfortunately. It’s got loads of different stuff in. and not only is it pretty complex stuff it stains carpets really badly too.

Functions of blood

Carries oxygen and nutrients to the cells throughout the body
Moves carbon dioxide from the cells to the lungs
Helps to maintains body temperature
Helps to maintains pH levels, fluid and electrolyte balance, necessary from homeostasis
Protects the body from excessive blood loss by clot formulation
It carries heat and waste products away from cells

Plasma is a pale straw-coloured liquid which carries just about everything.

Red and white blood cells and pastels.
Digested food products like glucose and amino acids.
Carbon dioxide from the organs to the lungs.
Urea from the liver to the kidneys.
Hormones.
Antibodies produced by the white blood cells.

A normal ECG

During the period of contraction the heart pumps blood out through the arteries during the period of relaxation the heart fills with blood. One complete sequence of filling and pumping blood is called a cardiac cycle, or heartbeat. The heart will beat without input from the nervous system and will continue to beat, even outside the body, as long as its cells are alive. The automatic nature of the heartbeat is referred to as automaticity. When you are physically active, your heart beats faster and harder, and pumps more blood to your lungs and the rest of your body's cells. When you are relaxed, your heart beats slower because your body's cells do not require as much oxygen and are not producing as many waste products.

Cardiac output is how much blood your heart is pumping out each minute. Cardiac output depends on two things: how many times the heart beats each minute; and how forcefully the heart contracts with each beat. The more forcefully the heart contracts with each beat, the more blood will be ejected from the heart with that beat.

Stroke volume (SV) is the amount of blood ejected from the heart with each individual contraction. An average adult has a stroke volume of 70ml.

70 x pulse rate = cardiac output (L/min)

Heart rate (HR) is the average resting heartbeat per minute of the . When resting, the average adult human heart beats at about 70 beats per minute (bpm) in males and 75 bpm in females. This rate varies among different people, and can be significantly lower in individuals who participate in endurance athletics. Heart rate is determined by measuring one's using a variety of methods. These can be specialized devices, or merely pressing one's fingers against an . If the stroke volume has increased to 100ml, the amount of blood pumped (the cardiac output) will be higher even with a slower heart rate.

100 x 55bpm = 5500ml/minute or 5.5 liters per minute.

Blood pressure is always given as these two numbers, the systolic and diastolic pressures. Both are important. Usually they are written one above or before the other, such as 120/80 mmHg. The top number is the systolic and the bottom the diastolic. When the two measurements are written down, the systolic pressure is the first or top number, and the diastolic pressure is the second or bottom number (for example, 120/80). If your blood pressure is 120/80, you say that it is "120 over 80."

The digestive system

Digestion is a complex process and a number of organs work together to complete the job. The Food passes through the alimentary canal which starts at the mouth and ends up at the anus. The alimentary canal is split into a number of sections which are adapted for a particular part of the digestive process.

Salivary glands produce the clear liquid that is released into the mouth (saliva, or spit). There are three pairs of major salivary glands and many minor glands. Saliva starts the breakdown of chewed food. It is made up of water, enzymes, mucin and protein.

The oesophagus transport food from the mouth to the stomach. Food is moved by peristalsis – muscular contractions of the oesophagus. Salivary amylase continues to act during the short journey to the stomach.

The stomach when the food reaches the stomach gastric juice is released from the stomach lining. Gastric juice contains two substances.

Pepsin - an enzyme which breaks proteins down into shorter chains called polypeptides.
Hydrochloric acid - needed to help pepsin work and also helps to kill any ingested bacteria.

The stomach has two rings of muscles at the top and bottom, called sphincter muscles which prevent food from leaving the stomach while it is being churned around. After a few hours, the food is now a mushy liquid called chyme. It is then allowed to continue on its journey a bit at a time.

The duodenum