Nutrition (human) Flashcards
What are the necessary food groups for a balanced diet?
Carbohydrates, Proteins, Lipids, Dietary Fibre, Vitamins, Minerals (mineral ions), Water.
Define malnutrition and provide an example.
- Malnutrition is an imbalance in nutrient intake.
- Example: Starvation - suffering or death caused by the lack of food.
What is the function of Vitamin C?
- Sticks together cells lining surfaces to make connective tissues.
- Deficiency: scurvy.
Name a source of dietary fibre.
Vegetables, whole grains.
How do energy requirements vary with age?
- The amount of energy needed increases as individuals grow, especially during periods of growth.
- Energy requirements decrease in older adults.
Why do pregnant women need extra calcium in their diet?
Extra calcium is needed for:
- the development of the fetus’s bones, and teeth
- To support the larger mass that the mother needs to carry.
Name the first part of the small intestine.
Duodenum.
What is the role of bile in digestion?
Bile neutralizes stomach acid and emulsifies lipids, breaking them into smaller droplets.
Explain the role of peristalsis in the alimentary canal.
Peristalsis is a mechanism that moves food along the alimentary canal through wave-like contractions of circular and longitudinal muscles.
Name an enzyme involved in the digestion of proteins.
Pepsin (produced in the stomach).
Where is bile produced and stored?
Bile is produced by the liver and stored in the gallbladder.
How is the small intestine adapted for absorption?
- highly folded surface with villi, increasing its surface area.
- Villi have microvilli
- one cell thick for a short diffusion distance
- an efficient blood supply to maintain the concentration gradient.
Explain the health effects of an unbalanced diet.
An unbalanced diet can lead to malnutrition, resulting in health issues such as starvation, coronary heart disease, constipation, and obesity.
Describe the role of the duodenum in the small intestine.
- The duodenum is the first part of the small intestine where amylase, protease, and lipase enzymes digest food.
- Bile is also released to neutralize stomach acid and emulsify lipids
How does peristalsis contribute to the movement of food in the alimentary canal?
Peristalsis involves wave-like contractions of muscles that push the bolus or chyme along the alimentary canal, facilitating digestion and absorption.
Discuss the functions of Vitamin D and its sources.
- Vitamin D helps the body absorb calcium for strong bones and teeth.
- Sources include oily fish, dairy products, and sunlight exposure
Explain the significance of the lacteal in the structure of a villus
- The lacteal transports fatty acids and glycerol away from the small intestine in the lymph
- leading to the absorption of lipids.
What must be increased/lacked in the diet of a person suffering from constipation?
Fibre
What condition could be caused by a lack of iron?
Anaemia
What is the result of a diet lacking iron?
Reduced number of red blood cells
What is assimilation?
Digested food molecules move into the cells of the body where they are used and become part of the cells.
What causes tooth decay? and which type of organism causes it?
- Acids released by bacteria
- Bacterium
Which organ secretes amylase?
Pancreas
What is the definition of chemical digestion?
Large insoluble molecules are changed into smaller soluble molecules.
