Human Digestive System

Question 1

Define human alimentary canal

Answer 1

Its a long tract/tube which connects with the external environment and can fulfill the steps of holozoic mode of nutrition

Question 2

What does the human digestive system consist of

Answer 2

Alimentary canal
Associated glands

Question 3

Components of alimentary canal

Answer 3

1. Mouth/Oral cavity
2. Pharynx
3. Esophagus
4. Stomach
5. Small intestine
6. Large intestine
7. Rectum
8. Anus

Question 4

Associated glands include

Answer 4

1. Salivary glands
2. Liver
3. Pancreas

Question 5

Describe oral cavity

Answer 5

• Oral cavity consists of tongue, teeth and salivary glands
• Ingestion and initial steps of digestion are carried out in oral cavity
• Both mechanical and chemical digestion takes place in the mouth

Question 6

Components of oral cavity

Answer 6

tongue
teeth
salivary glands

Question 7

Whats carried out in oral cavity

Answer 7

• Ingestion and initial steps of digestion are carried out in oral cavity
• Both mechanical and chemical digestion takes place in the mouth

Question 8

Describe teeth

Answer 8

• There are 4 teeth types: incisors, canines, premolars and molars
• Functions:
  1. Food is cut, mashed and ground by different teeth types with different shapes
  2. Makes it easier to swallow food
  3. Increases surface area for digestion

Question 9

Functions of teeth

Answer 9

1. Food is cut, mashed and ground by different teeth types with different shapes
2. Makes it easier to swallow food
3. Increases surface area for digestion

Question 10

Describe salivary glands

Answer 10

• Salivary glands release saliva into oral cavity through ducts
• Releasing saliva into the oral cavity occurs when food enters the oral cavity due to a nervous reflex
• Saliva is also released into the mouth before food digestion due to various other stimuli (ex: sight, odor of food)
• Saliva contains water, amylase, mucin (a viscous mixture of salts, cells and slippery glycoproteins called mucins), buffers and anti-microbial components

Question 11

what does saliva contain

Answer 11

water
amylase
mucus (a viscous mixture of salts, cells and slippery glycoproteins called mucins), buffers
anti-microbial components

Question 12

what is mucus

Answer 12

a viscous mixture of salts, cells and slippery glycoproteins called mucins

Question 13

how is saliva released to oral cavity

Answer 13

through ducts

Question 14

what are the 2 instances saliva is released into oral cavity

Answer 14

• Releasing saliva into the oral cavity occurs when food enters the oral cavity due to a nervous reflex
• Saliva is also released into the mouth before food digestion due to various other stimuli (ex: sight, odor of food)

Question 15

what are the stimuli that stimulate saliva release into mouth

Answer 15

sight

odor of food

Question 16

functions of saliva

Answer 16

1. Salivary amylase

Chemical digestion of polysaccharides (starch) into smaller polysaccharides and disaccharides into maltose

2. Water

Liquifies food

Provides a watery medium for chemical digestion

Aids in taste reception

3. Mucus

Lubricates food to make it easier to swallow

Cleans mouth

Protects mouth lining from abrasion

4. Antimicrobial components (lysozymes, immunoglobulin)

Protect against bacteria that enter the mouth

5. Buffers

Prevents tooth decay by neutralizing acid

Question 17

buffers function

Answer 17

Prevents tooth decay by neutralizing acid

Question 18

antimicrobial components function

Answer 18

Protect against bacteria that enter the mouth

Question 19

mucus functions

Answer 19

Lubricates food to make it easier to swallow

Cleans mouth

Protects mouth lining from abrasion

Question 20

salivary amylase function

Answer 20

Chemical digestion of polysaccharides (starch) into smaller polysaccharides and disaccharides into maltose

Question 21

water functions

Answer 21

Liquifies food

Provides a watery medium for chemical digestion

Aids in taste reception

Question 22

Give examples for antimicrobial components in saliva

Answer 22

lysozymes
immunoglobulin

Question 23

Describe tongue

Answer 23

• composed of skeletal muscles
• Functions:

1. Helps mix food with saliva and make food bolus that makes swallowing easier
2. Then helps push bolus into the posterior part of oral cavity into the pharynx

Question 24

composition of tongue

Answer 24

skeletal muscles

Question 25

functions of tongue

Answer 25

1. Helps mix food with saliva and make food bolus that makes swallowing easier 2. Then helps push bolus into the posterior part of oral cavity into the pharynx

Question 26

describe pharynx

Answer 26

- A common passage of the respiratory tract and digestive tract - The pharynx leads to esophagus

Question 27

what is pharynx the common passage of

Answer 27

respiratory and digestive tracts

Question 28

what does pharynx lead to

Answer 28

esophagus

Question 29

describe esophagus

Answer 29

- it's a long tube connecting pharynx and stomach - It's found in thoracic cavity - The wall of esophagus contains both skeletal and smooth muscles - The skeletal muscles are located towards the uppermost part of esophagus and these muscles function in swallowing - The rest of the esophagus contains smooth muscles involved in a process called peristalsis - Peristalsis is a process where food bolus is pushed along the esophagus, which is an alternative wave of rhythmic contractions and relaxations of the smooth muscles lining the esophagus

Question 30

where is esophagus found

Answer 30

thoracic cavity

Question 31

what does esophagus connect

Answer 31

pharynx and stomach

Question 32

what does the esophagus wall contain

Answer 32

smooth and skeletal muscles

Question 33

where are the skeletal muscles of esophagus found

Answer 33

towards the uppermost part of esophagus

Question 34

what do skeletal muscles in esophagus function in

Answer 34

swallowing

Question 35

what do smooth muscles in esophagus function in

Answer 35

peristalsis

Question 36

define peristalsis

Answer 36

Peristalsis is a process where food bolus is pushed along the esophagus, which is an alternative wave of rhythmic contractions and relaxations of the smooth muscles lining the esophagus