Bones, muscles, respiratory and circulatory systems.
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Unit 12- Physical Activities Skeletal system The human body has 206 bones. They are divided in to two parts, the Axial skeleton and the Appendicular skeleton. The Axial is made up of the skull, sternum, ribs and spine. The Appendicular is made up of the shoulder, hip, arm, leg and pelvic bone. In the skeleton system there are 4 types of bones, 6 types of joints and 3 classes of levers. There are four groups of bones they are long bones, short bones, flat bones and irregular bones. * The long bones are found in the thigh, legs, arms and forearms. They are longer than wider. They have compact bone in the middle, so that they are stronger and do not bend, they have spongy bone at the end so they are more flexible to move. * The short bones are usually found in the wrists and ankles. They are nearly as long as wide. They are mostly spongy, which gives them ability to move with a thin layer of compact bone. * The flat bones are mostly in the cranium. They are thin, usually curved and flattened. * The irregular bones are bones that do not fall into the other 3 groups, which are vertebrae and some of the bones in the cranium. These bones are spongy with a thin layer of compact bone. There are six different types of joints they are ball and socket joints, ellipsoidal joints, gliding joints, hinge joints, saddle joints and pivot joint.
Muscular system There are around 650 muscles in the human body, and they make up approximately half of our body weight. They can be divided into three different groups. They are the skeletal, smooth and cardiac. * The cardiac muscles exist only in the heart. They are involuntary muscles. * The smooth muscles are found in walls of hollow organs. They are voluntary muscles. * The skeletal muscles produces movement, maintain posture, stabilises joint and generates heats. They are voluntary muscles. Voluntary muscles are always slightly tensed which is called muscle tone. They contract to keep the body stabile when standing up and sitting down. Involuntary muscles contract and relax automatically, we can not control them. There are two different types of exercise contraction. They are isotonic and isometric. * Isotonic contractions are lifting exercises. The way it happens is that the muscles shorten as it contracts. * Isometric contractions are attempting to lift an immoveable object. The way it happens is that the there is tension on the muscle but no movement is made causing the length of the muscle to remain the same. The muscle pairs: Agonist (prime mover) * Biceps * Deltoids * Pectoralis Major * Rectus Abdominis * Iliopsoas * Quadriceps * Hip Adductor * Tibialis anterior Antagonist Triceps Latissimus dorsi Trapezius/Rhomboids Erector Spinae Gluteus Maximus Hamstrings Gluteus Medius Gastrocnemius An agonist is a muscle that causes movement to occur. An antagonist is a muscle that acts in opposition to the movement generated by the agonist.
Effects The energy systems Humans need energy to survive. It is used to allow us to breathe, move, pump blood in addition to all the things we do in our daily lives. We aquire energy through the food that we eat, and the amount in a particular piece of food is called the number of calories. Food has three building blocks, Carbs (4cp/g), Protein (4cp/g) and Fat (9cp/g) cp/g stands for calories per gram. Our bodies 'burn' the calories in food though metabolic processes by which enzhymes transform the 3 building blocks of food into these useful ones. Carbohydrates: glucose and other sugars Proteins: amino acids Fat: glycerol and fatty acids The after effects are then transported through the bloodstream to the bodily cells, where they are either absorbed for to use immediatly or sent on to the final stage of metabolism where they are reacted with oxygen to release their stored energy. Age, height and weight and lots of other factors decide just how much each individual needs in a day. your BMR (the basic amount of energy required to operate the body, regulate temperature, keep the heart beating and the lungs functioning.), physical activity and the thermic effect of food are the three things the energy is used for. For every 3500 calories that are eaten, it is stored as 1pound of fat, fat is the storage of energy which can be used when it is needed, so the opposite occurs when not enough is eaten, the same amount is converted into energy to be used by the body.
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