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Carbohydrate digestion

The average American diet is about 50 percent carbohydrates, which may be classified according to the number of monomers they contain of simple sugars (monosaccharides and disaccharides) and/or complex sugars (polysaccharides). Glucose, galactose, and fructose are the three monosaccharides that are commonly consumed and are readily absorbed. Your digestive system is also able to break down the disaccharide sucrose (regular table sugar: glucose + fructose), lactose (milk sugar: glucose + galactose), and maltose (grain sugar: glucose + glucose), and the polysaccharides glycogen and starch (chains of monosaccharides). Your bodies do not produce enzymes that can break down most fibrous polysaccharides, such as cellulose. While indigestible polysaccharides do not provide any nutritional value, they do provide dietary fiber, which helps propel food through the alimentary canal.

The chemical digestion of starches begins in the mouth and has been reviewed above.

In the small intestine, pancreatic amylase    does the ‘heavy lifting’ for starch and carbohydrate digestion ( [link] ). After amylases break down starch into smaller fragments, the brush border enzyme α-dextrinase    starts working on α-dextrin    , breaking off one glucose unit at a time. Three brush border enzymes hydrolyze sucrose, lactose, and maltose into monosaccharides. Sucrase splits sucrose into one molecule of fructose and one molecule of glucose; maltase    breaks down maltose and maltotriose into two and three glucose molecules, respectively; and lactase    breaks down lactose into one molecule of glucose and one molecule of galactose. Insufficient lactase can lead to lactose intolerance.

Carbohydrate digestion flow chart

This flow chart shows the steps in digestion of carbohydrates. The different levels shown are starch and glycogen, disaccharides and monosaccharides. Under each type of sugar, examples and the enzymes responsible for digestion are listed.
Carbohydrates are broken down into their monomers in a series of steps.

Protein digestion

Proteins are polymers composed of amino acids linked by peptide bonds to form long chains. Digestion reduces them to their constituent amino acids. You usually consume about 15 to 20 percent of your total calorie intake as protein.

The digestion of protein starts in the stomach, where HCl and pepsin break proteins into smaller polypeptides, which then travel to the small intestine ( [link] ). Chemical digestion in the small intestine is continued by pancreatic enzymes, including chymotrypsin and trypsin, each of which act on specific bonds in amino acid sequences. At the same time, the cells of the brush border secrete enzymes such as aminopeptidase    and dipeptidase    , which further break down peptide chains. This results in molecules small enough to enter the bloodstream ( [link] ).

Digestion of protein

This diagrams shows the human digestive system and identifies the role of each organ in protein digestion. A text call-out next to each organ details the specific function.
The digestion of protein begins in the stomach and is completed in the small intestine.

Digestion of protein flow chart

This flow chart shows the different steps in the digestion of protein. The four steps shown are protein, large polypeptides, short peptides and amino acids and amino acids.
Proteins are successively broken down into their amino acid components.

Lipid digestion

A healthy diet limits lipid intake to 35 percent of total calorie intake. The most common dietary lipids are triglycerides, which are made up of a glycerol molecule bound to three fatty acid chains. Small amounts of dietary cholesterol and phospholipids are also consumed.

Questions & Answers

I learned that anatomy is the study of the human structure. the smaller ones can be observed by the assistance of a microscope
Hawa Reply
what are the disciplines of anatomy
Bint Reply
what is the difference between anatomy and physiology
Addai Reply
the structure of human body the function of human body
Addai
anatomy is study of structure off the body and physioly is the study off function of body eg git
Dr
study of structure of the human body and study of function off the body eg git
Dr
nice 👍
qaseh
what does anatomy deal with
Kigani
anatomy deala with study of human structure eg human skeltal syatem
Dr
explain proximal in terms of anatomy body planes and give examples
Kwasi
don't know
Addai
anyone here MLT
Hussain
anatomy is the study structure of the human body. physiology is the study of function and mechanism of the body
Hamdi
I don't get the consent wrll
Joana Reply
sorry
Dawood
what's pathology
SABINA Reply
the science of the causes and effects of diseases
Emmi
yes dear you right
Tabish
ryt
Hussain
is the study of the abnormalities and how they affect body functions often causing illness
Frimpong
type of anatomy
yuns
what are cells
Mwenya
Cells are the basic structural and functional unit of all living organisms which they exist from pre-existing cells that self replicate on their own.
Tantoh
Cell is the structural , Function and heritability unit of life .
Juna
What is the function of liver
Sagir
liver helps in detoxification of toxic substances in our body and metabolism of drugs
sai
what is septum sacroti
Soul
What drugs use to treat liver diseases
Sagir
like ursodioxycholic acid
sai
liver disease medications depend on the type of liver disease..cirrhosis of the liver, no alcoholic liver disease, hep b, hep c.
Maria
what causes thyphoid
casmir
Maria what is carcinoma
Soul
What is ursodioxycholic acid
Sagir
No alcoholic liver diseases and help b, help c
Sagir
carcinoma is a type of cancer. it starts in the tissue lining the organs such as the liver or kidneys
Maria
describe the urine formation
Sarah Reply
Body water
Kashif
the urine formation is described as the wrist fluid that comes out of body
Hellen
glomerular filtration, reabsorption, secretion.
Maria
nice
Hussain
good Hellen kehn
Dr
is it wast fluids or wrist?
Baldwin
how many bones does human have?
Akech
Good
Opeyemi
206
Emmi
about the urine formation Baldwin asked that is it wast fluid or wrist that comes out from the body
Frimpong
waste fluids.. Tubular Reabsorption: Glucose, Amino acids, Proteins, Vitamins, Lactate, Urea, Uric acid, NA+, K+, Ca2+, Mg2+, Cl-, HCO3-, H20 Tubular Secretions: Urea, Uric acids, Creatinine, H+, NH4+, K+ Each different section of the Nephron has a different mineral that absorbs or secrets
Emmi
thank you Emmi
Baldwin
No problem, Happy to help.. I have a photo of exactly which area does what but I don't think I can attach on this platform..
Emmi
***socratic.org/questions/how-is-urine-produced-in-the-kidneys On this web page if you stroll down, there is a picture describing it. its my favorite diagram. Very clear and informative
Emmi
how can we access another platform to share more information
Baldwin
if you copy and paste that url.. it'll take you to the website I mentioned
Emmi
done.....
Baldwin
define what is a port of entry for microorganisms?
Baldwin
A port of entry is specific to that microorganism. for example, a bacterial infection of the urinary tract would have the vaginal area as the port of entry.
Emmi
droplets from one person to another is one 👍
Maria
or you can say that a viral microbe/flu would have a port of entry through the nasal cavity, mouth, or eyes because it is part of the respiratory system.
Emmi
in children more then 206 and in young man 206
Dr
emmi,you losing me .,. please make me clear on the question👆
Baldwin
nice Emmi
Hussain
children have 300
Alem
is female circumcision possible
Soul
noo, there is no possibility for circumcision in females
sai
Carcinoma is abnormal division of cells in the body without control
DECONS
female circumcision is technically considered a human rights violation and done in some countries where they partially remove the external female genitalia.
Maria
then again tubal ligation, I believe is like female circumcision. they tie or burn your tubes and you won't be able to have kiddos. so yes, its possible.
Maria
ok and so I mean not having kids .just kidding there I'm going to sleep.
Maria
Maria madam thank you for sharing this information
Soul
hello
Dawood
what is single cell
Jimmy Reply
A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. ... Many eukaryotes are multicellular, but many are unicellular such as protozoa, unicellular algae, and unicellular fungi.
Noor
Why is important to check if the blood if compatible before transfusion ?
Kelvin Reply
to avoid cases of intravenous clupping in blood which can be fatal....bcos blood is incopartable
John
Thank you.good answer
Kelvin
what are the clinical significant of thyroid gland
Jennifer Reply
what is a metabolism?
Kheth Reply
Metabolism is the sum total of all the chemical processes in the body. It is divided into an anabolic(building up) and catabolic(breaking down) metabolism)
Jonas
Oh ok
King
sir what is constructive and destructive metabolism
Soul
is anyone
Soul
Describe the system s that maintain the internal environment of a human body
Nora Reply
an organism is a living being that had a cellular structure and that can independently perform all physiological functions needed for life.
Nwecho Reply
a tissue is a group of similar cells that work together to perform a particular function
Nwecho
chemical level, cellular level, tissue level, organs level, organ systems, organisms
Nwecho Reply
they're reproduction but also produces hormones dus they're endocrine system
Nwecho
cells are smallest independent functional unit of a living organism
Nwecho
an organ is an anatomically distinct structure of the body composed of two or more tissue
Nwecho
an organ system is a group of organs that work together to perform a major function.
Nwecho
Structural Organization of the human body.
Tammy
very good
quophy
What is a cavity
Isaac Reply
Permanently damaged areas in teeth that develop into tiny holes
MASLAH
what is meant by epithelial tissue
Zahid
What is the difference between regional anatomy and systematic anatomy?
Andrew Reply
Regional anatomy is the study of the interrelationships of all of the structures in a specific body region, such as the abdomen. ... In contrast, systemic anatomy is the study of the structures that make up a discrete body system—that is, a group of structures that work together to perform a unique
Tammy
Pls is that all
Petra
regional anatomy studies structures that contribute to specific body region example the thoracic region while systematic anatomy studies structures that contribute to specific body systems example respiratory system
Nwecho

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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