Unit 8 talks about the physiology of the human body systems. The body has a total of 13 systems which all work together to maintain and regulate, 'homeostasis'. This Unit consists of three assignments A (Musculoskeletal system), B (Lymphatic system), and C (Digestive System) Overall, I received a d...
C.P5 EXPLAIN THE ROLE AND LOCATION OF ORGANS INVOLVED IN DIGESTION.
TOUNGE
MOUTH
PHARYNX
OESOPHAGUS
LIVER
STOMACH
PANCREASE
LARGE INTESTINE
Transverse colon
SMALL INTESTINE Sigmoid colon
Ascending colon
Duodenum GALL BLADDER RECTUM
ileum
Jejunum ANUS
1
, HAJRAH ALI (40157986)
THE MOUTH (BUCCAL CAVITY): Is where food enters the mouth and is physically broken down by our teeth and the movement of
our face muscles and jaw’s (mandible and maxillae) known as mechanical digestion. Smaller the molecules the larger the surface
area and easier to swallow with the saliva for easier digestion. The salivary glands secrete saliva which keeps the mouth cavity moist
and the enzyme salivary which starts chemical digestion and contains mucus for lubrication. This contributes to the digestive
process by helping the food move more easily through oesophagus without any discomfort as it breaks down food and salivary
glands in the mouth make saliva to help moisten this, saliva contains enzymes that begin to break down starch in the food.
TOUNGE: Is an organ which sits on the floor of the mouth and is covered with mucous, there are specialized epithelial cells named
basal and gustatory which allows the taste buds to taste the food and send messages to the brain which identify the food whether it
is bitter sweet salty or sour.
PHARYNX: (4-5inch long) Is a fibromuscular tube lined at the back of the throat using muscles joining the nose to the mouth and the
mouth to the oesophagus, the food which is being chewed in the mouth is rolled into a bolus by the tongue which pushes against
the roof of the mouth where the palates are located and then is followed by the swallowing movement as an automatic cranial
reflex.
OESOPHAGUS: Is connected from the mouth to the stomach and is where food soluble travel through to reach the stomach, it is
approx. 10inches long and 2.5 diameters. It is a muscular tube which allows the bolus to pass through and secretes mucus to
lubricate the bolus (ball off food) by peristalsis; involuntary muscle contraction of muscles to move food along. (Contraction and
relaxation). This helps push food down into the stomach where it is then churned for several hours and by peristalsis which is an
involuntary muscle contraction to move the food along.
STOMACH: Is an expandable muscular bag located in the upper abdomen below the diaphragm food enters from the oesophagus
and is digested after several hours. The muscular wall is long and smooth and is lined with muscle fibres and with epithelial cells
which produces gastric juice which help absorb Vitamin B12 and contains hydrochloric acid (pH1) to kill bacteria. The enzyme pepsin
starts the chemical process of breaking down protein, the wall generates a peristaltic movement to churn the food and mix it with
enzymes to form chyme. Within the stomach lining are glands which make stomach acid and enzymes to breakdown macronutrients
such as carbohydrates, proteins and lipids, and the stomach muscles help to churn the food with these digestive juices.
LIVER: Large gland and is the size of a football on the right-hand side of the abdomen quadrant helps body release toxic substances
and digestion by producing bile a digestive juice, this helps digestions of fats and some vitamins. The bile ducts carry the bile from
the liver to the gallbladder to store for later use or to the small intestine to be put in to use. Bile is a salt that has a high pH to help
neutralise stomach acid.
GALL BLADDER: 10cm thin green muscular sac located under the liver which stores and concentrates bile from the liver
and when it is needed it is released into the duodenum via bile duct, it is empty and flat after meals.
PANCREAS: Gland made up of exocrine and endocrine which secrete glucagon and insulin to control glucose blood levels and
Pancreatic juice secreted through the pancreatic duct, contains amylase protease and lipase, the enzymes help break down sugars,
fats and starches. They travel via ducts and release themselves In the duodenum of the small intestine.
SMALL INTESTINE (SI): is divided into 3 parts (Duodenum, Jejunum, Ileum).
The Duodenum (30cm) is the 1st part of the SI connects to the stomach and almost all the digestion takes place here. Due to
pancreatic juice, bile, and glands secreting maltose in the lining. The food here is called chyme as it is very acidic and partially
digested which mixes with mucus containing bicarbonate which neutralizes acid.
Jejunum is the 2nd part and chyme is moved by the movement peristalsis this is the middle section and most digestion/nutrient
absorption occurs here. Chyme is pushed into the microvilli (lining of the inner surface) so absorption of digested nutrients can
take place.
Jejunum is where most of the nutrient absorption takes place where:
Iron is absorbed
Vitamin B12 and Bile salts are absorbed in the ileum.
Water and lipids are absorbed by passive diffusion
2
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller hajrahali1. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £18.49. You're not tied to anything after your purchase.
