Ch 1 - Digestion and Absorption Flashcards
What is the most essential component of life?
Food
Why is food important for life?
The major components of our food are carbohydrates, proteins and fats. Vitamins and minerals are also required in small quantities. Food provides energy and organic materials for growth and repair of tissues.
What are the other two essential components in addition to food? Give reason
Roughage(Dietary Fibre) and Water
- Helps in easy digestion
- Prevents dehydration, regulates body temperature and helps in metabolic processes.
Define “Digestion”
The process of conversion of complex food substances to simple absorbable forms is called digestion
How is digestion carried out?
Digestive system through biochemical (enzymes) and mechanical methods(mouth and stomach)
What makes up the digestive system?
Alimentary Canal and Associated glands.
Explain about the Alimentary Canal
- Also called GI tract
- 7 compartments
- Anterior and Posterior
Explain about the human buccal cavity
- Set of teeth
- Tongue
Define “ Dentition”
Arrangement, type of teeth and number of a species set of teeth
What is a human being’s type of dentition?
Theocodont
Diphyodont
Heterodont
Define Theocodont
Each tooth is embedded in a socket of jaw bone.This type of attachment is called thecodont.
Define Diphyodont
Majority of mammals including human being forms two sets of teeth during their life, a set of temporary milk or deciduous teeth replaced by a set of permanent or adult teeth. This type of dentition is called diphyodont.
Define Heterodont
An adult human has 32 permanent teeth which are of four different types (Heterodont dentition), namely, incisors (I), canine (C), premolars (PM) and molars
(M).
Number of human teeth
32
Define “Dental Formula”
Arrangement of teeth in each half of the upper and lower jaw in the order I, C, PM, M is represented by a dental formula which in human is 2123/2123 .
Explain about the tongue
The tongue is a freely movable muscular organ
attached to the floor of the oral cavity by the frenulum
What holds the tongue to the floor of the oral cavity?
Frenulum
Explain “Pappilae”
The upper surface of the tongue has small projections called papillae, some of which bear taste buds.
Elaborate on the oesophagus
The oesophagus is a thin, long tube which extends posteriorly passing through the neck, thorax and diaphragm and leads to a ‘J’ shaped bag like structure called stomach. (Peristalsis)
Define Pharynx
The oral cavity leads into a short pharynx which serves as a common passage for food and air.
Define “Epiglottis” and “Glottis”
A cartilaginous flap called epiglottis prevents the entry of food into the glottis – opening of the wind pipe – during swallowing.
Define and explain the structure and location of stomach
The stomach, located in the upper left portion of the abdominal cavity, has four major parts – a cardiac portion into which the oesophagus opens, a fundic region, body
(main central region) and a pyloric portion
which opens into the first part of small intestine.
Which spinchter controls movement of food from oesophagus to stomach?
Gastro oesophagul spinchter
Define and explain the structure and location of small intestine
Small intestine is distinguishable into three regions, a ‘C’
shaped duodenum, a long coiled middle portion jejunum and a highly coiled ileum.
Which spinchter controls movement of food from stomach to small intestine?
Pyloric Spinchter
Define and explain the structure and location of large intestine
Ileum opens into the large intestine. It consists of caecum, colon and rectum. Caecum is a small blind sac which hosts some symbiotic micro-organisms. A narrow finger-like tubular projection, the vermiform appendix which is a vestigial organ, arises from the caecum. The caecum opens into the colon. The colon is divided into four parts – an ascending, a transverse, descending part and a sigmoid colon. The descending part opens into the rectum which opens out through the anus.
Why is caecum called “blind sac”?
The caecum is called blind sac because caecum looks like a sac which has sphincter at the ileocaecal junction and it remains closed and is invisible.
Which part of the large intestine is called a vestigial organ and why?
Vermiform appendix because it’s useless.
Who hosts symbiotic microorganisms and why?
Caecum
-helps in indigestion
Describe the transverse section of the gut or the alimentary canal.
4m+1m(diagram)
_________ epithelium has ___________cells that produce____________ for ____________.
Mucosal
goblet
mucous
lubrication
How many salivary glands are there in body?
6 (3p)
Name them and where are they located?
Parotid gland - cheeks
Submaxilliary/Submandibular - Lower jaw
Sublingual - under tongue
What do salivary glands secrete ?
saliva…duh 🙄
What is the largest gland in the body?
Liver
How much does liver weigh?
1.2-1.5kg
Where is liver located?
In abdominal cavity under diapghram
How many lobes does the liver have?
2
Liver Question:-
—————-is known as the ————- and ——————unit of the liver.
Hepatic lobules
functional
structural
Each of the hepatic lobule is covered with ————–.Define ———-.
Glisson’s capsule is a thin connective tissue sheath arranged in the form of chords.
What does the liver secrete?
Bile juice
Who in the liver produces the bile juice?
Hepatic cells
Where is the bile stored? And define.
Gall bladder is a muscular bag like structure that stores bile juice.
How is bile transported to gall bladder?
Through hepatic duct
The————duct and the ———duct(also known as————duct) form the common bile duct.
hepatic
bile
cystic
The bile duct and ——————-duct form the ————————-and open into the —————— and is guarded by————–spinchter
pancreatic
common hepato pancreatic duct
duodenum
oddi