Digestive System Flashcards
1
Q
What are the different nutrient groups?
A
- Proteins
- Carbohydrates
- Lipids (fats)
- Vitamins
- Minerals
- Fibre
- Water
2
Q
What are the stages of bird digestion?
A
- Tongue
- Crop
- Proventriculus
- Ventriculus (the gizzard)
- Ceca
- Cloaca
3
Q
What are the stages of monogastric digestion?
A
- Mouth (teeth and tongue= mechanical digestion) (saliva = chemical digestion)
- Stomach (hydrochloric acid and enzymes =chyme)
- Small intestine (duodenum, jejunum and ileum)
- Liver
- Pancreas
6.Large intestine (colon, caecum and rectum)
7.Anus
4
Q
What are the stages of ruminant digestion?
A
1.rumen (fermentation)
2. Peristalsis (undigested feed=cud)
3.Reticulum (filters food)
4.Omasum (absorbs water and salt)
5.Abomasum (digestive enzymes and acid are added)
5
Q
What is mechanical digestion and chemical digestion?
A
- Mechanical digestion is where food is physically broken down into smaller pieces (chewing/mastication- oral cavity churning- stomach/rumenbile- duodemungrinding-gizzard)
- Chemical digestion is where food is broken down by enzymes, acid and bile (intestines)
6
Q
Define autotroph
A
- An autotroph is able to synthesis ‘food’ from it’s surroundings using light or chemical energy e.g photosynthesis
7
Q
Define heterotrophic
A
- Heterotrophic species cannot synthesise energy from their environment and therefore rely on others such as plants or animals for nutrition
8
Q
Define maxillary and mandibular
A
- Top layer of teeth (maxillary)
- Bottom layer of teeth (mandibular)
9
Q
What is the function of the liver?
A
- Stores vitamin A, D,E,k & B12
- Mineral storage (copper&iron)
- Carbohydrate storage
- Bile production
10
Q
What is the function of the pancreas?
A
- Detects blood glucose concentration, releases hormones that alter the amount of glucose in the body
- Secretes glucagon and insulin to control levels
11
Q
How is the regulation of blood glucose performed?
A
- Blood glucose is regulated by the pancreas in a homeostatic process
- Pancreases detect levels, then releases hormones to regulate
12
Q
What happens when Hyperglycaemia occurs?
A
- Pancreas detects high blood glucose levels
- Insulin is secreted (by beta cells)
- Glucagon secretion decreases
- Insulin travels via the blood to the target organ (liver&muscles)
- Excess glucose is converted to glycogen by the liver and stored in the muscles - used to make energy
13
Q
What happens when hypoglycaemia occurs?
A
- Pancreas detects low blood glucose levels
- Glucagon is secreted (by alpha cells)
3 Insulin secretion decreases - Glucagon travels via the blood to the target organ (liver and muscles)
- Glycogen is converted back into glucose by the liver and muscles - released back into blood
14
Q
What are the roles of insulin?
A
- Released from pancreas
- Converts glucose to glycogen
- Insulin secreted when blood sugar levels are high
- Insulin lowers blood glucose/ removes glucose from the blood
- Involved in regulating blood glucose/homeostasis
15
Q
What are the roles of glucagon
A
- Glucagon is released from the pancreas/liver
- Glucagon converts glycogen to glucose
- Glucagon is secreted when low levels of sugar/glucose
- Glucagon raises blood glucose/ releases glucose into the blood
- Involved in regulating blood glucose/homeostasis
16
Q
What are the different types of nutrient groups and their functions?
A
- Carbohydrates- (for energy)
- Fibre- (bulk movement through digestive tract)
- Protein- (for amino acids to make body proteins such as cells, tissues, enzymes, hormones, muscles and hair)
- Lipids/fats- (stored for energy and used for insulation and protection of organs)
- Vitamins- (for specific chemical reactions in cells)
- Minerals- (for bones and teeth, osmoregulation, nerve transmission and muscle contraction)
- Water- (involved in chemical reactions, transporting chemicals and regulating body temperature)
17
Q
Mechanical and chemical digestion within ruminant digestion
A
- Rumen- chemical digestion
- Reticulum - mechanical digestion
- Omasum - filters food
- Abomasum - chemical digestion
18
Q
Mechanical and physical digestion within bird digestion
A
- Crop- storage
- Proventriculus - chemical digestion
- Ventriculus / the gizzard -mechanical digestion
19
Q
Explain the role of protein in the diet of a pregnant dog
A
- Repair and maintenance of body tissue
- Puppies growing and developing new tissues
- Protein needed for milk production
20
Q
Explain a feature of the dental structure for a herbivore
A
- Flat teeth - designed to grind
- Hard dental pad -for crushing
21
Q
Explain a feature of the dental structure for a carnivore
A
- Canines -used to rip meat
22
Q
Explain two reasons why carbohydrates are important in the diet of an animal
A
- Provide energy - essential for brain/movement of muscles
- Excess carbohydrates stored as fat- for keeping warm/storing energy
23
Q
Explain two functions of the liver
A
- Production of bile to emulsify fats
- Regulating blood glucose by storing and releasing glucose
24
Q
State one cause and one symptom of ruminant bloat
A
- Cause - incorrect diet
- Symptom- distress
25
Explain the role of water in a cats diet
1. Prevents dehydration- so cells/organs can function effectively
2. Improves the effectiveness of digestion- increasing nutrient absorption
26
Explain how intestinal villi are adapted to absorb biological molecules
1. Large surface area / many microvilli - so more molecules can be absorbed
2. Good blood supply to allow increased diffusion of molecules
3. Thin walls efficient for diffusion
27
Explain two ways a cow’s mouth is adapted to eat grass
1. Dental pad- grip grass
2. Flat teeth- allow side to side chewing
28
Explain one way birds break down their food without having teeth
1. They have a gizzard - to grind food with stones from grit they have swallowed
2. They have a beak to tear/crack food to reduce size
29
Explain two ways birds’ beaks are adapted to feed
1. Strong hard- to break nuts
2. Sharp pointed - to pick up small pieces of food or spear fish
3. Sharp hooked beaks - to tear meat
30
Give three examples of mechanical digestion
1. Churning stomach /reticulum
2. Ventriculus / the gizzard - grinding
3. Teeth- chewing
31
Explain one way intestinal villi help the absorption of nutrients
1. Finger like projection which increase surface area
2. Network of capillaries- to allow efficient diffusion/ absorption of molecules
32
Compare the roles of the hormones insulin and glucagon
1. Insulin is secreted when blood sugar levels are too high
2. Insulin is released from the pancreas
3. Insulin converts glucose to glycogen
4. Insulin is involved in regulating blood glucose
5. Glucagon is released from the pancreas
6. Glucagon converts glycogen to glucose
7. Glucagon is involved in regulating blood glucose
8. Glucagon is secreted when blood sugar levels are low
33
Organs and functions of a bird’s digestion system
1. Crop - stores food
2. Proventriculus- chemical digestion/enzyme action/hydrochloric acid
3. Ventriculus/The Gizzard - mechanical digestion/ grinding food
4. Cloaca - eliminate waste
34
What are the edible faeces rabbits produce called?
1. Caecotropes
35
What is the function of the caecum in hindgut fermenters?
1. Where large numbers of microbes ferment the food
36
What is the key difference in hindgut fermenters
1. They do most of their digesting after their stomach
37
Where does chemical and mechanical digestion take place within a hindgut fermenter?
1. Mechanical digestion: Mouth-teeth-grinding, Stomach- churning
2. Chemical digestion: Liver-bile production, Pancreas- production of digestive enzymes, Caecum- fermentation/microbes/enzymes
38
Where does mechanical and chemical digestion occur within a ruminant?
1. Mechanical digestion: teeth-grinding plant material, reticulum- filters food
2. Chemical digestion: Mouth-saliva- amylase, Rumen- fermentation/microbes, Abomasum (true stomach) digestive enzymes/acids
39
Where does mechanical and chemical digestion take place within a monogastric digestion system?
Mechanical digestion: Mouth-teeth-chewing, Oesophagus-peristalsis, Stomach-grinding
Chemical digestion: Mouth-saliva-amylase, Stomach- hydrochloric acid/enzymes, Duodenum-enzymes
40
How are carnivores adapted to eat meat?
1. Canines- hold prey, pierce skin and rip meat
2. Carnassial teeth- shear meat
41
How are herbivores adapted to eat plant material?
1. Incisors- cut plant material
2. Molars- continually grow and worn down by silica in plants
42
How are omnivores adapted to eat plant material and meat?
1. Incisors and canines are used to cut meat
2. Flat molars are used to grind plant material
43
Explain two reasons why carbohydrates are important in the diet of an animal
1. Carbohydrates are the main source of energy, essential for brain/movement of muscles
2. Simple carbohydrate/sugar short-term store, to provide quick energy
44
What are three functions of the liver?
1. Production of bile to emulsify fats
2. Involved in regulation of blood sugar by storing and releasing glucose
3. Removing toxins from the blood
45
Discuss how blood sugar levels are maintained in animals
1. Blood glucose levels are maintained primarily by the actions of insulin and glucagon in a negative feedback loop
2. As blood glucose levels increase the pancreas responds by secreting insulin
3. Insulin stimulates in the liver and and skeletal muscle cells to the form glycogen from glucose
4. Insulin stimulates liver cells and adipose tissue to synthesis fat from glucose
5. As blood glucose levels decrease glucagon (hormone) is produced
6. Glucagon stimulates the liver and skeletal muscle cells to breakdown glycogen to glucose
46
What is the function of incisors?
1. Fine nibbling/cutting/delicate grooming
47
What is the function of canines?
1. Holding prey and tearing meat
48
What is the function of premolars?
1. Shearing flesh, grinding food
49
What is the function of molars?
1. Shearing and grinding
50
What is the function of canines?
1. Hold prey, pierce skin and rip meat
51
What is the function of carnassial teeth?
1. Allow shearing of meat
