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Flashcards in 6.1 Deck (21)
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1

What happens in digestion in the mouth?

Food is mechanically mixed and amylase is secreted

2

What happens in digestion in the esophagus?

Peristalsis

3

What happens in the stomach in digestion?

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

4

What happens in the pancreas in digestion?

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

5

What happens in the large intestine in digestion?

Vitamins are reabsorbed and undigested polysaccharides are fermented to produce energy

6

What happens in the small intestine in digestion?

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

7

What is peristalsis?

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

8

Where does peristalsis take place?

In the esophagus to the stomach

9

What happens to the muscles in peristalsis?

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

10

How long is the small intestine?

6-7m in humans

11

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

30-60 fold

12

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

Serosa, muscle layers, mucosa, sub mucosa, villi

13

Where do enzymes come from in the small intestine?

The wall

14

What does the small intestine produces?

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

15

Where does absorption of actual food molecules are place?

Over the epithelium

16

What is directly absorbed by the villi?

- bases and phosphates from nucleic acids
- fatty acids and glycerol
- amino acids
- monomeric carbohydrates

17

Where are food molecules, minerals and vitamins absorbed into?

The blood or the lymph

18

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

They need to pass through capillaries of villus

19

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

They circulate into the lacteal

20

How do monosaccharides enter the epithelium?

By sodium- glucose channels in facilitated diffusion

21

How do amino acids enter the epithelium?

Pumped against the concentration gradient