Nutrition Flashcards
Our nutrition is composed of?
- Vitamins
- Minerals
- Fats
- Proteins
- Carbohydrates
- Water
What does each nutrition give us? (except water)
Fats and Carbohydrates give us energy and our used for building blocks
Minerals give: Homeostasis, signalling, cofactors, structural
Vitamins: required co-factors that cannot be made —> Essential nutrients that cannot be synthesized
What are the essential nutrients? And how do we obtain them?
- minerals
- vitamins
- essential amino acids (9)
- essential fatty acids
- All must be obtained through food
- What is essential varies by the organism
What are the 2 essential fatty acids?
Essential fatty acids: linoleic acid and alpha-linolenic acid ( omega 6 and 3 fatty acids)
What about the rest of the fatty acids?
Rest of the fatty acids can be synthesized from a-linolenic acid
What is missing in humans?
W-6 and w-3 desaturase missing in humans (W = omega)
W-3 and W-6 polyunsaturated fatty acids (PUFAs) ratio matters:
- Low W-3 PUFA, high W-6 PUFA can cause chronic inflammation. (Western diet - red meat, fast food)
- High W-3 PUFA, low W-6 PUFA is healthy . (Mediterranean diet - fish certain veggies)
What is cholesterol?
Precursor for many steroid hormones , common pathway in animals and plants
Insects can’t make what and why?
Insects can’t make steroid hormones because they miss one enzyme: cholesterol is a vitamin (or other steroids)
Why is vitamin D important? And how do people with less sunlight get Vitamin D?
- Vitamin D important: reduces chances of osteoporosis.
- In areas with less sunlight, Vitamin D is a supplement in food.
What is the digestive process steps?
- Ingestion: taking food into digestive tract
- Digestion: Breakdown into smaller pieces
- Absorption: Uptake of nutrients
- Elimination: disposal of waste
What is the incomplete digestive tract?
Food comes into the mouth → pharynx → gastrovascular cavity
What is the complete digestive tract?
when food enters the mouth and leaves out of the anus. (Alimentary canal)
Human digestive tract?
Mouth → esophagus → Stomach → Small intestine → Large intestine → Anus
The mouth contains?
The liver, gall bladder and pancreas produce?
salivary glands
enzymes that help breakdown food
Carbohydrates breakdown process?
start getting digested in the mouth (salivary amylase).
Gets turned into Monosaccharides or di/tri saccharides in the lumen of small intestine (Pancreatic amylase)
Epithelium of small intestine is where monosaccarides get diffused into the bloodstream
Lipids breakdown process?
starts getting digested in the mouth (Lingual lipase)
Lipids turn into monoglycerides and fatty acids in the lumen of the small intestine by bile salts and pancreatic lipase
In the epithelium of small intestine, monoglycerides fatty acids turn to triglycerides which goes to chylomicrons. Chylomicrons go into the bloodstream my exocytosis.
Protein breakdown process?
start getting digested in the stomach by Pepsin which turn into polypeptides. Also contains pepsinogen which are pro-enzymes
In the lumen of the small intestine, Trypsin and other enzymes turn polypeptides in short peptides Amino acids
In the epithelium of small intestine it turns to amino acids and by diffusion and cotransporters goes into the bloodstream
What is peristalsis?
- Muscle contraction constricts esophagus above food
- Muscle contraction moves like a wave down the esophagus, pushing the food below it into the stomach
What does the sphincter do?
Sphincter seals off stomach from esophagus so food doesn’t come back up.
What is the stomach coated with and why?
Stomach is coated with mucus so proteins aren’t attacked by the stomachs pH acid
Explain the effect of bile salts on large fat globules.
- Large fat globules are not digested quickly by lipase
- Bile salts (produced by liver) act as emulsifying agents.
- Small fat droplets result from emulsification
- Lipase digests the small fat droplets into monoglycerides and free fatty acids.
Bile salt is…
A bile salt is an amphyiphillic molecule: a detergent that emulsifies lipids
What happens with water in the Intestines? Small and Large?
Water is absorbed in small intestine but residual water is resorbed in the large intestine’s colon
Reason why are feces are compacted
Symbiotic microorganisms produce many compounds
