110 likes | 250 Views
National 4 Science. Human Health A Healthy Body and Body Fat. Body Fat. Learning intentions: What does the body need fat for? Name a low tech method of measuring body fat Name a high tech method of measuring body fat What is the body mass index BMI
E N D
National 4 Science Human Health A Healthy Body and Body Fat
Body Fat • Learning intentions: • What does the body need fat for? • Name a low tech method of measuring body fat • Name a high tech method of measuring body fat • What is the body mass index BMI • What effect does being underweight have on the body? • What effect does being obese have on the body?
Why does the body need fat? • The body needs fat: • As an energy store – fat releases twice as much energy per gram compared to carbohydrate • Absorbs shock in the form of fat pads on hands and feet • Is essential to transmit nerve impulses • Acts as a layer of insulation under the skin
Measuring body fat • Low tech method of measuring body fat: • Skin fold calliper • High tech method of measuring body fat: • Body fat sensor
Body fat reading • Using p74 of textbook work out your body fat using the readings you have just taken • Stand on the body fat sensor • What is your body fat? • Is the reading similar to that obtained using the skin fold callipers? • Which method is more accurate?
What is healthy fat? • Males require a body fat content of 15-20% of his total mass • Females require a body fat content of 20-25% of her total mass
What is body mass index, BMI? • There is an ideal body mass for everyone • Body mass is affected by: • Height • Age • Gender • BMI = body mass (kg) height (m)2 • Calculate your BMI • Body mass = _______kg • Height = _________m • Using the graph on p75 of textbook work out your BMI
What effect does being over or under weight have on the body? • Copy and complete the following using the words below kidney failure anorexia arthritis cancer heart disease diabetes • Losing a lot of weight over a short time can indicate ___________ and _________ • Being over weight (obese) can lead to __________ __________, ___________ _________ and __________ • can explain being very underweight.
Quiz • What does the body need fat for? • Name a low tech method of measuring body fat • Name a high tech method of measuring body fat • What is BMI? • What effect does being underweight have on the body? • What effect does being obese have on the body?