Blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium. As the atrium contracts, blood flows from your right atrium into your right ventricle through the open tricuspid valve.

To avoid pregnancy and STDs, always remember to use a condom every time you have sex — including oral, vaginal, or anal sex. Whenever oral sex is being performed on a girl, a dental dam should be used. A guy receiving oral sex should wear a latex condom — or, if he or his partner is allergic to latex, a polyurethane condom.

Marfan syndrome is a genetic disorder that affects the body's connective tissue. Connective tissue holds all the body's cells, organs and tissue together. It also plays an important role in helping the body grow and develop properly. Connective tissue is made up of proteins.

This baby was born with an adult sized tongue - and she just completed a surgery that will change her life.

A breech birth occurs when a baby is born bottom first instead of head first. Around 3-5% of pregnant women at term (37–40 weeks pregnant) will have a breech baby. Most babies in the breech position are born by a caesarean section because it is seen as safer than being born vaginally.

here may be no symptoms of stomach cancer early on. Later, symptoms include feeling bloated after eating, feeling full after eating small amounts of food, nausea, heartburn, or indigestion.

Histology of Aorta Elastic Stain

Dealing with bleeding

Histology of Female Urethra

Sinusitis means your sinuses are inflamed. The cause can be an infection or another problem. Your sinuses are hollow air spaces within the bones surrounding the nose. They produce mucus, which drains into the nose. If your nose is swollen, this can block the sinuses and cause pain. There are several types of sinusitis, including Acute, which lasts up to 4 weeks Subacute, which lasts 4 to 12 weeks Chronic, which lasts more than 12 weeks and can continue for months or even years Recurrent, with several attacks within a year Acute sinusitis often starts as a cold, which then turns into a bacterial infection. Allergies, nasal problems, and certain diseases can also cause acute and chronic sinusitis. Symptoms of sinusitis can include fever, weakness, fatigue, cough, and congestion. There may also be mucus drainage in the back of the throat, called postnasal drip. Your health care professional diagnoses sinusitis based on your symptoms and an examination of your nose and face. You may also need imaging tests. Treatments include antibiotics, decongestants, and pain relievers. Using heat pads on the inflamed area, saline nasal sprays, and vaporizers can also help.

Histology of Small Intestine Illeum

Renal artery stenosis is a narrowing of arteries that carry blood to one or both of the kidneys. Most often seen in older people with atherosclerosis (hardening of the arteries), renal artery stenosis can worsen over time and often leads to hypertension (high blood pressure) and kidney damage.

Skin cancer is the most common type of cancer. There are three major types of skin cancer — Basal Cell Carcinoma, Squamous Cell Carcinoma and melanoma. Out of these, Melanoma is the deadliest form of skin cancer. Melanoma appears on the skin as a new spot or growth or a change in an already existing mole. It is often fast growing and can spread to other parts of your body, including your bones, liver, and lungs to form a new cancer.

Lack of sunshine causes skin cancer, according to Andreas Moritz. In this video from 2009, he explains why being in the sun is actually good for you and your skin. Find out why your sunscreen is doing more harm than good. Also, you need vitamin D to prevent cancer, and sunscreen may interfere with your exposure to vitamin D from the sun.

Explained (Balloon Sinuplasty and Endoscopic Sinus Surgery)

Histology of Adrenal

A computed tomography (CT) scan uses a special X-ray machine to take detailed pictures of the body’s organs and tissues. In a biopsy, a small piece of tissue is removed from your body. This tissue sample is then examined in the lab. A needle biopsy is the safest and easiest way to remove this tissue safely from the body. To do a needle biopsy, the radiologist will insert a needle through your skin and into your tissue. A syringe or an automated needle may be used to take the tissue sample.

If you look at someone’s back, you’ll see that the spine runs straight down the middle. When a person has scoliosis, their backbone curves to the side. The angle of the curve may be small, large or somewhere in between. But anything that measures more than 10 degrees is considered scoliosis. Doctors may use the letters “C” and “S” to describe the curve of the backbone. You probably don’t look directly at too many spines, but what you might notice about someone with scoliosis is the way they stand. They may lean a little or have shoulders or hips that look uneven. What Causes Scoliosis? In as many as 80% of cases, doctors don’t find the exact reason for a curved spine. Scoliosis without a known cause is what doctors call “idiopathic.” Some kinds of scoliosis do have clear causes. Doctors divide those curves into two types -- structural and nonstructural. In nonstructural scoliosis, the spine works normally, but looks curved. Why does this happen? There are a number of reasons, such as one leg’s being longer than the other, muscle spasms, and inflammations like appendicitis. When these problems are treated, this type of scoliosis often goes away.

Small colon polyp (redish bump)and many diverticuli (small outpouches in wall of the colon)

How Respiratory Pump Affects Venous Return