Nutrition And Digestion Flashcards
Autotrophic organisms
Use photosynthesis to obtain nutrients
Heterophic organisms
Consume food in order to obtain energy and nutrients
Food required to maintain a balanced diet
- Carbohydrates
- Protein
- Lipids (fats and oils)
- Vitamins
- MInerals
- Water
- Fibre
Carbohydrates
50% of daily intake
Function of carbohydrates
Source of immediate and stored energy
Effect if there is a shortage of carbohydrates in the body
Lose weight and less energy
Protein
15% of daily intake of food
Function of proteins
- Building material: makes and repairs cells and tissues
- Maintains healthy cells and tissues
- Makes anti-bodies to fight infection
Effect if there is a shortage of protein in the body
- Kwashiorkor in children
- Low immunity and weak muscle development
Lipids (fats and oils)
35% of daily intake of foods
Function of lipids (fats and oils)
- Source of reserved or stored energy
- Insulates the body against the cold
- Help absorb fat soluble vitamins (K;A;D;E)
- Surrounds kidneys and acts as a shock absorber
Effects if there is a shortage of lipids (fats and oils) in the body
- Stunted growth
- A lack of fat soluble vitamins
Function of vitamins
- Make sure chemical reactions take place correctly in cells
- Provides resistance to disease
Effect if there is a shortage of vitamins in the body
Different diseases
Function of minerals
- Ensures normal development and growth
- Controls substances to ensure good health
Effect if there is a shortage of minerals in the body
Different diseases
Function of water
- Body consists mainly of water
- All life-processes need water
- Provides fluid for cell reaction
Effect if there is a shortage of water in the body
- Dehydration
- Large loss = death
Function of fibre
- Promotes peristalsis and keeps food moving through the digestive system
- Keeps faeces moist
- Prevents constipation, piles and colon cancer
Effect if there is a shortage of fibre in the body
- Constipation
- Colon cancer
What determines the amount of energy used by individuals
- Age
- Gender
- Levels of activity
Energy and proteins: growing children and teenagers need ____ adults
> more than
Food: Males need ____ females
> more than
Energy rich foods: athletes need ____ non-athletes
> more than
Food: older people need ____ younger people
< less than
Cause of rickets
Vitamin D and/or calcium deficiency
Main part of the body affected in rickets
Bones
Symptoms of rickets
- Soft-bones
- Bow-legs (legs become bent)
Cause of scurvy
Vitamin C deficiency
Main part of the body affected in scurvy
Blood vessels
Symptoms of scurvy
- Bleeding gums and loose teeth
- Bleeding under the skin and bruising
- Sores that don’t heal
- Low resistance to infection
- Getting sick often
Cause of anaemia
Iron deficiency
Main part of the body affected in anaemia
Red blood cells
Symptoms of anaemia
- Tiredness
- Paleness
- Weakness
- Dizzy
- Rapid heart rate and palpitations
Cause of kwashiorkor
Protein deficiency
Symptoms of kwashiorkor
- Rounded abdomen/belly
- Very thin arms and legs
- Tires easily
- Puffy face
- Weakness
Treatment for kwashiorkor
- Powdered milk
- Soya beans
- Eggs
- Fish and meat
Cause of marasmus
Lack of energy-rich food (carbohydrates) and protein deficiency
Symptoms of marasmus
- General body wasting
- Very low body weight
- Severe muscle-wasting and retarded growth
- ‘monkey-like’ appearance
- Weakness, irritable and hungry
Cause of anorexia nervosa
Insufficient food
Symptoms of anorexia nervosa
- Little energy
- Fainting
- Thin skin
- Constipation
- Can result in death
Treatment for anorexia
- Doctor
- Dietitian
- Therapist
Cause of bullimia nervosa
Lose control on a restrictive diet, and later purge
Symptoms of bullimia nervosa
- Self-induced vomiting
- Compulsive eating
- Damage to teeth
- Bloating
- Bleeding of the rectum
Cause of obesity
- Overeating
- Bad eating habits
Symptoms of obesity
- Heart attacks
- High blood pressure
- Type 2 diabetes
- Stroke
- Infertility
Treatment for bulimia nervosa
- Family therapy
- Cognitive Behavioural Therapy
- Dietary counselling
- Physchodynamic therapy
- Medication
Plants are autotrophic
They make their own food
Animals are heterotrophic
They eat plants/animals for the energy and nutrients
Why do we need to eat?
- Maintain body processes (vitamins and mineral salts)
- Growth and repair of all cells and the production of hormones, enzymes and anti-bodies (protein)
- Supply energy to the body (carbohydrates and fats)
Nutrition involves 5 key processes
- Ingestion
- Digestion
- Absorption
- Assimilation
- Egestion
Lifestyle of herbivore
Little competition for food
- Browsers eat leaves from shrubs
- Grazers eat grass
Lifestyle of a carnivore
- Predators hunt for prey, catch them and eat them
- Scavengers eat off the carcass once the predators have eaten their fill
Lifestyle of an omnivore
In some cases are predators/generally live in groups and share food
Teeth and ingestion of a herbivore
Sharp even incisors, flat premolars and molars
Teeth and injestion of a carnivore
Pointed incisors and enlarged canines
Teeth and injestion of a omnivore
Teeth use for meat and vegetable diet. One 1 half of each jaw has 2.1.2.3.
Stomach (digestion) of a herbivore
More than one stomach to digest cellulose. Presence of mutualistic bacteria to produce enzymes to digest cellulose in plants
Stomach (digestion) of a carnivore
Well-developed stomach with gastric juice that enables the digestion of proteins and bones
Stomach (digestion) of an omnivore
Well-developed stomach with gastric juices to digest proteins and fats
Energy relationship of a herbivore
Primary consumers must consume large amounts of plant material to meet their energy requirements
Energy relationship of a carnivore
Secondary consumers eat primary consumers. Require less food because their diet is rich in proteins
Energy relationship of an omnivore
Tertiary consumers consume the least amount of food as diet is rich in all require nutrients
Mechanical digestion involves
- Chewing food, mastication
- Bolus formation (saliva and tongue)
- Peristalsis, muscle action move the food along the alimentary canal
- Churning movement of stomach to mix chyme
Human teeth
2.1.2.3.
2.1.2.3.
- Incisors
- Canines
- Premolars
- Molars
Function of salivary glands
- Stimulates taste buds
- Helps clean the teeth
- Helps form chewed food into a bolus
- Makes sure small food pieces stick together
- Contains salivary amylase
- Contributes to the process of chemical digestion in the mouth
Bile is used to:
- Neutralise acidic chyme
- Physically breaks down fats in to small droplets
Bacteria in colon contains these vitamins:
- Vitamin K - helps with blood clotting
- Biotin (Vitamin B7/H)
- Vitamin Bs
