2. Nutrition, Body Weight and Homeostasis Flashcards Preview

4. Metabolism > 2. Nutrition, Body Weight and Homeostasis > Flashcards

Flashcards in 2. Nutrition, Body Weight and Homeostasis Deck (41)
Loading flashcards...
1
Q

Define energy.

A

The capacity to work.

2
Q

Define 1Kcal.

A

The amount of energy needed to raise temperature of one kilo gram of water by one degree Celsius.

3
Q

What is the conversion rate of Kcal and kJ?

A

1 Kcal = 4.2 kJ.

4
Q

What is intake of carbohydrate used for?

A

For supplying energy.

5
Q

What is intake of protein used for?

A

Energy and amino acids.

6
Q

What is intake of fat used for?

A

Energy and essential fatty acids.

7
Q

What is intake of water used for?

A

Hydration.

8
Q

What is intake of fibre used for?

A

Normal GI function.

9
Q

What are the main dietary carbohydrates?

A

Starch (carbohydrate storage molecule in plants), sucrose (table sugar), lactose (milk sugar), fructose (from fruit), glucose (sugar in human blood).

10
Q

How many different amino acids are used for protein synthesis?

A

20.

11
Q

How many essential amino acids, that can’t be synthesis so must be obtained from diet, are there?

A

9.

12
Q

What are the nine essential amino acids?

A
Isoleucine
Lysine
Threonine
Histidine
Leucine
Methionine
Phenylalanine
Tryptophan 
Valine
13
Q

Why does fat produce much more energy when oxidised?

A

It contains less oxygen than carbohydrates or proteins.

14
Q

Which vitamins are fat-soluble?

A

A, D, E and K.

15
Q

What are minerals used for in the body?

A

Establishing ion gradients across membranes and maintaining water balance.

16
Q

Why are vitamins needed in the body?

A

A deficiency of them lead to diseases.

17
Q

What can a low fibre intake lead to?

A

Constipation and bowel cancer.

18
Q

What can a high fibre do?

A

Reduce cholesterol and diabetes risk.

19
Q

What are dietary reference values (DRV)?

A

A series of estimates of the amount of energy and nutrients needed by different groups of healthy UK population.

20
Q

What are nutrient requirements dependent on?

A

Age, gender and level of physical activity.

21
Q

How are estimated average requirements (used for energy) estimated?

A

Requirement for 50% of the group, so half the group will need more than what the EAR suggests.

22
Q

How are reference nutrient intakes (for mineral) estimated?

A

The level where the need of 97.5% are met, many in the group will need less.

23
Q

How are lower reference nutrient intakes (LRNI) estimated?

A

The amount that is enough for only a small number of people (2.5%) so the majority need more than this.

24
Q

What causes variation in the energy requirements of people?

A

Age, sex, body composition and physical activity.

25
Q

What is daily energy expenditure the sum of?

A

Basal metabolic rate, diet-induced thermogenesis (energy required to process food) and physical activity level.

26
Q

What is the basal metabolic rate?

A

The energy needed to maintain resting activities of the body, like maintenance of cells (ion transport and biochemical reactions), function of organs and maintaining body temperature.

27
Q

What factors affect BMR?

A

Body size, gender, environmental temperature, endocrine status and body temperature.

28
Q

What is energy used for during physical activity?

A

Contraction of skeletal muscle, cardiac muscle and respiratory muscle.

29
Q

What is the order that the following stores of energy are used? Muscle protein, muscle, carbohydrate and adipose.

A

Muscle, carbohydrate stores, adipose, muscle protein.

30
Q

What is the most noticeable difference between a 70kg and 100kg man in terms of body composition?

A

Lipid stores, approximately 12kg for the 70kg man but 40kg for the 100kg man.

31
Q

Define obesity.

A

Excessive fat accumulation in adipose tissue that impairs health. BMI of over 30 kg/m2.

32
Q

What is the formula for calculating BMI?

A

BMI = weight (kg) / height2 (m2)

33
Q

What is an alternative measurement of weight classification to BMI?

A

Hip to waist ratio.

34
Q

Name two complications that upper body fat increases the risk of.

A

Insulin resistance/type II diabetes, hyperinsulinism, hypertension, hyperlipidaemia, stroke or premature death.

35
Q

What causes Kwashiorkor?

A

Low protein intake from malnutrition so resulting in insufficient blood protein synthesis and decreased plasma inciting pressure, which leads to oedema.

36
Q

What are the 6 main functions of blood?

A

Transport (of oxygen, nutrients, waste products and hormones), coagulation, immune functions, regulating body pH, regulating body temperature and hydraulic functions.

37
Q

Define homeostasis.

A

Mechanisms that counteract changes in the internal environment to maintain a dynamic equilibrium.

38
Q

What is the general outline of a homeostatic response?

A

Receptor detects change, control centre sends signal to counteract change, effectors bring about the desired change, negative feedback corrects the deviation.

39
Q

How are blood glucose levels maintained after eating?

A

Pancreas secretes insulin, insulting stimulates liver to take up glucose to store as glycogen and tissues take up glucose, plasma glucose levels decline back to normal.

40
Q

How are blood glucose levels maintained in a fasted state?

A

Pancreas releases glucagon, glucagon stimulates liver to break down glycogen and real ease glucose into the blood, plasma glucose levels rise back to normal.

41
Q

Explain the difference between catabolic and anabolic processes.

A

Catabolic processes break down molecules to release energy in the form of reducing power but anabolic processes use energy and raw material to make larger molecules for growth and maintenance.