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Flashcards in 6.1 Deck (21)
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1
Q

What happens in digestion in the mouth?

A

Food is mechanically mixed and amylase is secreted

2
Q

What happens in digestion in the esophagus?

A

Peristalsis

3
Q

What happens in the stomach in digestion?

A

Food is mixed with gastric juice, which contains HCL and protease is secreted, producing chyme and polypeptides, and bacteria are killed

4
Q

What happens in the pancreas in digestion?

A

Amylase, lipase and endopeptidase are secreted, digesting food into monomers

5
Q

What happens in the large intestine in digestion?

A

Vitamins are reabsorbed and undigested polysaccharides are fermented to produce energy

6
Q

What happens in the small intestine in digestion?

A

Neutralisation occurs, lipase and amylase are secreted and most of the absorption takes place

7
Q

What is peristalsis?

A

The wave of contraction and relaxation of the longitudinal and circular muscles of the alimentary canal, by which the contents are forced ahead

8
Q

Where does peristalsis take place?

A

In the esophagus to the stomach

9
Q

What happens to the muscles in peristalsis?

A

The longitudinal and circular muscles work antagonistically, so the longitudinal contracts to widen the lumen, whilst the circular contracts to constrict the lumen

10
Q

How long is the small intestine?

A

6-7m in humans

11
Q

How much does villi increase the small intestines surface area by?

A

30-60 fold

12
Q

What are the layers of the small intestine, starting from the outside going in?

A

Serosa, muscle layers, mucosa, sub mucosa, villi

13
Q

Where do enzymes come from in the small intestine?

A

The wall

14
Q

What does the small intestine produces?

A

Monosaccharides, amino acids, fatty acids and glycerol, vitamins, mineral ions

15
Q

Where does absorption of actual food molecules are place?

A

Over the epithelium

16
Q

What is directly absorbed by the villi?

A
  • bases and phosphates from nucleic acids
  • fatty acids and glycerol
  • amino acids
  • monomeric carbohydrates
17
Q

Where are food molecules, minerals and vitamins absorbed into?

A

The blood or the lymph

18
Q

Where do food molecules, minerals and vitamins from the blood pass into the small intestine?

A

They need to pass through capillaries of villus

19
Q

Where do fats from the lymph pass through the small intestine?

A

They circulate into the lacteal

20
Q

How do monosaccharides enter the epithelium?

A

By sodium- glucose channels in facilitated diffusion

21
Q

How do amino acids enter the epithelium?

A

Pumped against the concentration gradient