Download Heterotroph can`t synthesize organic compounds from inorganic

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Heterotroph can't synthesize organic compounds from inorganic molecules
Autotroph require only inorganic compounds absorbed from the environment for growth
and use energy from the sun (photosynthesis)
Organic compound that provide chemical energy:
-Carbohydrates (sugar, starch&fibre): main energy source, low GI ( a measure of how
simple the carbohydrate is and how quickly it is digested)
-Lipids (fats & oils): energy and structural component of cells, also vitamins
-Protein: can provide energy as well as amino acids for synthesis of new proteins (enzymes,
structural components of cells, etc.)
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Animals also need amino acid to build new proteins, fatty acids, vitamins (organic
compounds essential for metabolism), minerals (inorganic elements essential for
metabolism) and water.
Vitamins must be obtained from food. It is needed in small amounts for normal
functioning.. Vitamins can't be stored.
-Fat soluble: A,D,E, K
-Water-soluble: B group, C, niacin, folic acid, etc.
Rickets may occur due to lack of vitamin D->Softening of bond, causes deformity.
Normally occur in children. Vitamin D can be obtained from sunlight.
Scurvy-may occur due to lack of vitamin C->causes bleeding, skin spots, loss of teeth.
-Vitamin C can be obtained by consuming fruits and vegetables (especially citrus fruits)
Hypervitaminosis A- Excess vitamin A stored in liver of many carnivores in poisonous. So
when the carnivores is consumed, it causes excess of vitamin A.
Animals need minerals elements in different amount.
Essential minerals: Na, Cl, K, Ca, P, Mg, S (>100mg/day)
Trace elements: Fe, Cu, I, F, SE (<< 100mg/day)
Goitre is the swelling of thyroid/neck due to deficiency of iodine. It can be prevented by
dietary intake of iodine (e.g. iodized salt)
How much food an animal need depends upon metabolic rate, age, reproductive state.
Metabolic rate depends upon activity, body mass, environmental condition (hot or cold)
and the type of food and its ability to digest it.
Metabolic rate
Size plays a big role in metabolic rate
Big animals need more energy that small ones BUT per unit body mass, small animal need
more energy.
Small animals need more food per unit body mass and more energy-rich food.
Small animals have high metabolic rate per unit mass.
Digestion is the stepwise breakdown of large molecules into smaller ones to be absorbed
across gut wall to provide energy.
There are 2 types of digestion: mechanical digestion and enzymatic digestion.
Mammalian digestive system is a hollow, muscular tube consisting of: buccal cavity/mount
(+ salivary gland), pharynx, oesophagus, stomach, small intestine (+ pancreas, liver), large
intestine (including caecum), anus.
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Different enzymes come from different locations in the digestive tract: salivary glands,
stomach, liver, pancreas and small intestine-> sequential order of action and is pH
dependent.
Buccal cavity
- Physical breakdown of food by mastication (chewing)
They have different teeth for different food.
-Mixing with saliva: lubrication and enzymatic breakdown.
Pharynx-it is where oral and nasal cavity come together.
Oesophagus transports food in the form of bolus to stomach.
Stomach
-Mechanical breakdown: Muscular wall churns food.
-Chemical breakdown: acidic (HCl, pH: 1-2), enzymes
-Food reduced to soup (chyme)
-Pyloric sphincter (ring of muscle at the exit of the stomach) allows chyme into duodenum
Small intestine:
-Muscular tube (duodenum, jejunum, ileum)
-Enzymatic digestion
-Absorption of nutrients into bloodstream (both diffusion and active transport)
-Large surface area (many villi->fast absorption)
Digestive glands release enzymes into the small intestine
-Membrane of intestinal wall (with villi) secretes enzymes to break down mainly sugar.
-Pancreatic fluid from pancreas (lots of enzymes, break down protein)
-Bile: from liver stored in gall bladder, emulsifies fat
Large intestine is important for removal of water, formation of faeces and elimination
through anus.