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The cecum blends seamlessly with the colon    . Upon entering the colon, the food residue first travels up the ascending colon    on the right side of the abdomen. At the inferior surface of the liver, the colon bends to form the right colic flexure    (hepatic flexure) and becomes the transverse colon    . The region defined as hindgut begins with the last third of the transverse colon and continues on. Food residue passing through the transverse colon travels across to the left side of the abdomen, where the colon angles sharply immediately inferior to the spleen, at the left colic flexure    (splenic flexure). From there, food residue passes through the descending colon    , which runs down the left side of the posterior abdominal wall. After entering the pelvis inferiorly, it becomes the s-shaped sigmoid colon    , which extends medially to the midline ( [link] ). The ascending and descending colon, and the rectum (discussed next) are located in the retroperitoneum. The transverse and sigmoid colon are tethered to the posterior abdominal wall by the mesocolon.

Large intestine

This image shows the large intestine; the major parts of the large intestine are labeled.
The large intestine includes the cecum, colon, and rectum.

Homeostatic imbalances

Colorectal cancer

Each year, approximately 140,000 Americans are diagnosed with colorectal cancer, and another 49,000 die from it, making it one of the most deadly malignancies. People with a family history of colorectal cancer are at increased risk. Smoking, excessive alcohol consumption, and a diet high in animal fat and protein also increase the risk. Despite popular opinion to the contrary, studies support the conclusion that dietary fiber and calcium do not reduce the risk of colorectal cancer.

Colorectal cancer may be signaled by constipation or diarrhea, cramping, abdominal pain, and rectal bleeding. Bleeding from the rectum may be either obvious or occult (hidden in feces). Since most colon cancers arise from benign mucosal growths called polyps, cancer prevention is focused on identifying these polyps. The colonoscopy is both diagnostic and therapeutic. Colonoscopy not only allows identification of precancerous polyps, the procedure also enables them to be removed before they become malignant. Screening for fecal occult blood tests and colonoscopy is recommended for those over 50 years of age.


Food residue leaving the sigmoid colon enters the rectum    in the pelvis, near the third sacral vertebra. The final 20.3 cm (8 in) of the alimentary canal, the rectum extends anterior to the sacrum and coccyx. Even though rectum is Latin for “straight,” this structure follows the curved contour of the sacrum and has three lateral bends that create a trio of internal transverse folds called the rectal valves . These valves help separate the feces from gas to prevent the simultaneous passage of feces and gas.

Anal canal

Finally, food residue reaches the last part of the large intestine, the anal canal    , which is located in the perineum, completely outside of the abdominopelvic cavity. This 3.8–5 cm (1.5–2 in) long structure opens to the exterior of the body at the anus. The anal canal includes two sphincters. The internal anal sphincter    is made of smooth muscle, and its contractions are involuntary. The external anal sphincter    is made of skeletal muscle, which is under voluntary control. Except when defecating, both usually remain closed.

Questions & Answers

why human body can exit
how masturbation is harmful to boy or man
Horsico Reply
It's not. It's actually healthy.
masturbation is very healthy for men and women, making love is great for raising your immune system and cardiovascular system, as well as assists with other organ systems, keeps humans in great health physically and mentally with a good sexual routine in a well balanced relationship.👌👌👌
its a bad habit, and not good for health. it destroyes your hope and humanity. its causes depression and many mental disorders which lead to the person to stay loniless life. it causes to decrease your sexual sensitivity, in it decreased the quilty of sperm.
its leads to infertity and increases the risk of having congenital babies. it causes you to stay alone and kills the hope you want to get married or to have a spuse or partner. i will recommend you to stop if you are doing, that bad habit. you will feel health and hope.
To avoid that schedule your time, read more about it, exerices and be alweys busy, youl will not enjoy or desire to do it that. your will be smart and stay strong. Good morning to you all.
Is Masturbation Healthy? Yes absolutely.. release sexual tension. reduce stress. help you sleep better. improve your self-esteem and body image. help treat sexual problems. relieve menstrual cramps and muscle tension. strengthen muscle tone in your pelvic and anal areas.
Masturbation is not bad at all. it's just that some religious people sees it as a sin that's what makes it seem like it wrong but not really in reality. Its actually good for your well-being.
Masturbation may be both healthy and harmful to the body, if u make it a habit it can be extremely harmful but if not u are safe, either ways my advice is dont do it
we are not looking at the side of religion, but at medical and health to human and life of the person is not good for.
We know at the side of some religions its a something bad and sin. the reason it becomes sin means that its not good for health. in Islam prohibited every thing which is not good for health and causes to mental problems.
it's not a sin actually, that's a lie rewritten in the bibles. The LORD said be fruitful and multiply he's not gonna make masturbation a sin, don't harm the innocent that's a sin, don't judge another that's a sin, love and forgive all GOD LAWS 3 KARMA
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cellular,organ, molecules,chemical, tissue,organ system
Rofiat Reply
cellular,organ, molecules,chemical, tissue,organ system
cell is the functional and independent unit
Rofiat Reply
what is meiosis
limilian Reply
cell division of prophase 1 will not take place
the process by which cell development is form
am interested in joining this group, what are some of the requirements?
dennis Reply
what are the conquences of negative feed back of homeostasis mechanism
Negative & Positive Mechanism
Negative & Positive Mechanisms
Negative & Positive Mechanism
it cause effects in opposite side to stimulators.eg increasing co2 cause decreasing co2 in lung.posative is cause disease and death b/ce it produce stimulas in the same side to initial stumulas
posative eg blood clotting,birth of childetc
what are fluid compartment
Ngwenyi Reply
what is an aqueous solution
why are Sodium ions and Chloride ions often referred to as electrolytes
They are referred to as electrolytes because they have the tendency to undergo electrolysis. They are electrolytic in nature.
thank you for that answer, now I have a better understanding of the terms,
explain briefly about the frank- starling law and its mechanism
what is system
Aminata Reply
hey am new here
hello annisha
system is the collection of organs
how to make note
Mary Reply
hello I am new could you please explain it to me,?
who discovered the cell
Mwesigwa Reply
Robert Hooke
Hi am Prince am new here
Asare Reply
Yeah hw uu
Hi ....Mitchell's here am new here
welcome moraa
from which campus
I'm natasha I'm 14
Hi I am najeeb Ullah from Pakistan
Hi. I'm Abdull and I'm new here
hello I'm Aisha
useful app i have never seen before!
hi can we create a whatsap group for brainstorming?
please very important 08060555274 👒
very important the idea of creating a group
no problem
muscles of upper limb
pelvic has 2 Bones each Bone has two parts name the parts
Luchindo Reply
what and what
Inomenet bone
describe the structure of an atom
Obulejo Reply
what is mitosis?
atom is made of protons, nuetran and elections, which is very particle cannot be destructive nor be creative,
mitosis increase in size for separation new cell with its component including nucleus and it's content,
what are the abdominal region
I love how people can ask questions and receive answers 👌 great course btw 🙏
Global Reply
yes I wud also like to much because we can know aboth each and every thing in a deciplinary manner

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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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