Flashcards in Unit 2: Food and Health Deck (130)
Loading flashcards...
0
What is a balanced diet?
Provides all nutrients and energy needed to sustain life
1
What are nutrients needed for?
Better health
Stronger immune system
Learn more effectively
To increase productivity
2
What are the 7 main food groups and what do they provide for the body?
Carbohydrate-main source of energy
Proteins-growth and repair of muscle and tissues
Fats-biggest source of energy, cell membranes, waterproofing, absorption of fat soluble vitamins
Vitamins-roles in chemical processes
Minerals- inorganic elements essential to normal functions
Water-transporting substances around body
Fibre-essential for healthy functioning of digestive system
3
What does changes to weight show about energy in the diet?
Losing weight= too little energy in diet
Gaining weight= too much energy in diet
4
What are the body categories for BMI?
Less than 18.5 = underweight
18.5-25= healthy
25-30= overweight
30-35=obese (class 1)
35-40= obese (class 2)
Over 40= morbidly/ severely obese (class 3)
5
Why is BMI not an accurate measure of body mass?
Person may be pregnant
Person may have lots of muscle-make them heavier than average person
BMI not suitable for children
6
What is obesity?
When the body weight of a person is 20% or more above the weight recommended for your height
7
Why is obesity classed as a form of malnutrition?
The person is not getting the right amounts of each food group
Increased amounts of fatty foods
Little exercise
Social and economic stress lead to comfort eating
Physiological problems eg underactive thyroid gland
8
What diseases are so societies with obesity?
Coronary heart disease
High blood pressure
Angina (sufficient blood flow to heart but coronary arteries can't cope with exercise, results in chest pains)
Varicose veins
Type 2 diabetes
Osteoarthritis
Gall stones
9
How is salt linked to heart disease?
Salt-excess salt levels decrease water potential of blood=high diastolic pressure
-> hypertension
-> damage to artery walls, starting atheroscerlosis leading to HD
10
How is fat linked to heart disease?
Balance of fats needed (sat fats and unsat fats)
An excess of sat fats can lead to atheroscerlosis, leading to HD
11
What is the difference between low density lipoproteins and high density lipoproteins?
LDL= sat fat, cholesterol and protein
HDL= unsat fat, cholesterol and protein
12
How are polyunsaturated fats and monounsaturated fats useful to us?
Polyunsaturated fats=increase the number of receptors available for LDLs so more cholesterol enters tissues
Monounsaturated fats=remove LDLs from blood
13
Short term effects of tar? (4)
Settles in airway and alveoli linings- increases diffusion distance for gaseous exchange
Chemicals in tar can cause allergic reactions-causes smooth muscle contract
Tar paralyses/destroys cilia and stimulates goblet cell production
Trapped bacteria in mucus means lungs more susceptible to infection
14
Long effects of tar? (3)
Smokers cough
Frequent infections
Lung cancer
15
What does a smokers cough do to the airways?
Caused by tar irritating the airways and the need to clear blocked airways
-> Cough damages airway and alveoli lining which gets replaced with scar tissue=thicker and less flexible
-> layer of smooth muscle in bronchioles thickens, lumen narrows and flow of air permanently restricted
16
How do frequent infections, caused by smoking, result in damage to lining and layer of epithelium?
Infections attract WBC to deal which pathogens
-WBC have to enter airways
-to enter airways, enzyme used to break through lining walls (elastase), damaging elastic tissue of lining of lungs
17
How does smoking cause lung cancer?
Cigarettes contain carcinogenic compounds which cause cancer-found in tar lying on surface of lungs
Carcinogens enter lung tissue cells, enter nucleus and mutate the genetic material
-> if mutation affects genes for cell division, leads to uncontrollable cell division
18
Where does lung cancer often start developing?
At the entrance to the bronchi as this is where smoke deposits tar in the airways
19
Why are cancers difficult to detect?
Lung cancer can take 20-30 years to develop, meaning it might be years before the cancer is actually discovered
20
Name 4 diseases associated with smoking
Chronic bronchitis
Emphysema
Chronic obstructive pulmonary disease
Lung cancer
21
What are the causes and symptoms of chronic bronchitis?
Causes= inflammation of airways with damage to cilia and overproduction of mucus lead to mucus collecting in lungs
Symptoms= lung irritation, continued coughing, coughing up mucus with bacteria and WBC
22
What are the causes and symptoms of emphysema?
Causes=loss of elasticity in alveoli causing alveoli to burst -> decreases SA for gaseous exchange
Symptoms=shortness of breath especially when exerting themselves, in extreme cases breathing is shallow and rapid leading to fatigue
23
What is chronic obstructive pulmonary disease?
Combination of chronic bronchitis emphysema and asthma
24
What are the symptoms of lung cancer?
Continual coughing, shortness of breath, chest pain and blood coughed up in sputum
25
What effect does nicotine have on smokers?
It's the addictive chemical. The smoker gets used to the effects and becomes addicted.
26
What are the specific effects of nicotine on a smoker and why?
Increased sensitivity, feel more alert-nicotine mimics action of transmitter substances at synapses between nerves
Increased blood pressure-nicotine releases adrenaline, increased heart rate and constriction of arterioles
Restricted blood flow to extremities-nicotine causes constriction of arterioles=decreased blood flow and oxygen delivery
Increased risk of blood clot or thrombus-nicotine makes platelets more sticky
27
What effect does carbon monoxide have on smokers?
Decreases affinity for oxygen
Forms carboxyhaemoglobin (more stable and combines more readily than oxygen)
Lower oxygen levels may cause heart rate to rise
Can also damage lining of arteries
28
Name 4 problems caused by changes to blood system
Atheroscerlosis
Thrombosis
Stroke
Coronary heart disease
29
