1. High-density lipoprotein
   Low-density lipoprotein
2. It's a myth.
   All cholesterol is good cholesterol.

HDL cholesterol is good for you because it carries the bad LDL cholesterol back to the liver from other places in the body, so that it can be processed.

1. Under 50 bpm
   Over 100 bpm
2. 30-70 bpm
   60-100 bpm

This depends on a lot of factors like how big you are, but generally speaking you want to be between 60-100 bpm. If you're very fit, you might be between 45-60 though, as your heart gets stronger and does not need to work as hard.

1. Less than than 180 over 120, more than 160 over 110
   Less than 120 over 80 and more than 140 over 90
2. More than 120 over 80 and less than 140 over 90
   Between 120 over 70 and 140 over 90

120 over 70 is fine, 140 over 90 is fine-ish. Lower or higher could cause trouble.

1. How fast your blood goes
   How elastic your arteries are
2. Literally, pressure, as in pounds per square inch
   Whether you have enough blood

Blood pressure is how fast your blood is going and with how much force - that is, if it's too low, maybe you haven't got enough blood (literally), but more likely it means it's not being pumped with enough force. If it is too high, you might have blockages or inelastic blood vessels.

1. 500,000
   1,170,000
2. 610,000
   340,000

One in four deaths is due to heart disease, so take care of the little fella!

1. A sign of a heart attack
   A whooshing sound
2. When your heartbeat is irregular
   When your heart is too weak

A whooshing sound between beats is called a heart murmur. It can be totally benign or incredibly serious. If you have one and it doesn't go away, please, get yourself checked out. It might be nothing, but wouldn't you rather know?

1. Nothing
   Some of them are neurons.
2. They beat on their own.
   They are red.

If you put human heart cells in a petri dish, as long as they are alive, they'll beat. They don't care if they are attached to a heart: those tough little guys will beat, God help them.

1. Atria
   Valve
2. Sulci
   Ventricles

The little chambers are atria and the big ones are ventricles.

1. A new valve
   A ring around your blood vessel to hold it open
2. A tube in your blood vessel to hold it open
   A Band-Aid for a blood vessel

A stent is a little tube that goes in a large blood vessel that has ruptured or narrowed. It used to be very serious having one put in, and while it is no picnic now, it's not nearly as terrifying as it was.

1. Stroke
   Heart attack
2. Aneurysm
   Atherosclerosis

A heart attack is when you have a blockage that deprives your heart of oxygen, and heart tissue can actually die. It's very serious, but often treatable if you get help quickly.

1. No difference
   Arteries are bigger.
2. Veins take blood toward the heart, arteries bring it back.
   Arteries take blood away from the heart, veins bring it back.

As your biology teacher probably put it, "A, A, arteries away!" Arteries carry oxygen-rich blood away from the heart, veins bring oxygen-poor blood back to it.

1. Blue
   Red
2. Clear
   Black

Blood is red, it's just redder when it is oxygenated. Your veins look blue under your skin due to the way light passes through or is reflected by skin.

1. Brain damage due to suddenly limited blood supply to the brain
   A blockage in a blood vessel in the brain
2. Bleeding in the brain
   When your heart attack is so bad it damages your brain

If your blood supply to your brain is disrupted, you can have a stroke. This might happen for many reasons. A stroke is also called a brain attack, as it is characterized by brain tissue dying. It's very important to be treated within an hour to save the brain tissue.

1. A blood valve
   A little blood vessel
2. A big blood vessel
   An internal wall in the heart

The capillary is the smallest kind of blood vessel, and you have many, many thousands of them!

1. Drooping face
   Arm weakness
2. Slurred speech
   All of the above

Stroke patients may also get tingling, pain, dizziness or all sorts of other problems. Think FAST: that's Face, Arms, Speech, and Time to call 911.

1. 500 gallons
   200 gallons
2. 2,000 gallons
   5,000 gallons

You only have 1.2 to 1.5 gallons of blood in your body but it goes round and round so that your blood has to pump 2,000 per day.

1. 1,000 miles
   5,000 miles
2. 10,000 miles
   60,000 miles

Your blood vessels are 60,000 miles long, which is over 1/5 of the way to the moon!

1. Christmas Day
   Independence Day
2. New Year's Day
   Blue Monday

Christmas Day is when people eat and drink far more than is good for them while pretending to like all of their relatives (invariably including one who they frankly don't). The combination of indulgence and stress can kill!

1. The Epic of Gilgamesh
   The Book of Daniel
2. The Book of Genesis
   The laws of Draco

The Book of Daniel is in the New Testament and is the first account of going green to stay healthy.

1. 50,000
   200,000
2. 150,000
   100,000

The heart beats 100,000 beats a day!

1. To the outside of the heart
   To the lungs
2. To the legs
   To the rest of the body

It goes from the left to the lungs, and from the right to the rest of the body.

1. 1 minute
   10 minutes
2. 8 minutes
   4 minutes

Some people can hold their breath longer than this, but they certainly cannot make their heart stop that long. They would definitely die.

1. Cardio-physical resumption
   Cardiopulmonary resuscitation
2. Cardiopulmonary rejigging
   Central pulmonary rewiring

CPR is when you resuscitate a person whose breathing or heart has stopped, and manually make it work until it can be made to start working again on its own.

1. Restart your heart
   Make your heart go back to normal rhythm
2. Stop your heart briefly so it can start itself again
   Nothing, it's a placebo.

It doesn't actually restart your heart, it just makes it go back to a better rhythm if it is going too fast or going irregularly.

1. An artificial heart to replace your heart
   A partial replacement for your heart, replacing one half of it
2. An artificial device for stimulating the heart muscle and regulating its contraction
   A device to unblock your heart's valves daily

Pacemakers save lots of lives as they help people's heart rate stay regular.

1. 5 bpm
   8 bpm
2. 11 bpm
   15 bpm

Women's hearts go about 8 beats per minute faster than men's, on average. This is not always the case, though, so if your heart is faster or slower than your opposite-gender friends, don't worry.

1. Cornea
   Lung
2. The heart itself!
   Kneecap

This is one reason that a corneal transplant is so likely to be accepted by the body.

1. 100-150 bpm
   50-80 bpm
2. 70 to 160 bpm
   150-200 bpm

Babies have very fast little hearts. Listening to them on a stethoscope is very exciting!

1. The heart expands.
   The heart shrinks.
2. The interior walls of the heart get thinner.
   The heart starts tilting to the left.

Having a big heart is only a good thing in a non-literal way. If your heart is very sick, it can expand to twice the size of a regular heart!

1. 20%
   80%
2. 60%
   100%

This is good news as it means you can radically alter your odds of keeling over from a heart attack!

1. A dime
   A half-dollar coin
2. A quarter
   A nickel

A healthy valve is the size of a half-dollar coin.

1. Heart cells stop dividing early in life.
   Heart cells can't get cancer.
2. Heart cells always recognize cancer and kill it.
   It's not, it's just rare that people get treated - because by the time you know you've got it, you've died of it.

Cancer means uncontrolled cell division, so it struggles to happen in places where there isn't any cell division going on.

1. 1.2 seconds
   0.5 seconds
2. 0.3 seconds
   0.8 seconds

Your heart doesn't always do these at the same speed and there's a little gap between them, but generally speaking, they take about 0.8 of a second each.

1. Your nose gets bigger.
   Your shoes get tighter.
2. Your hat size goes up.
   Your skin is tighter.

If your body retains too much water, that might be a sign that your heart is weak.

1. Of course!
   Obviously not.
2. Only if you were already sick
   Only if you have an underlying genetic condition

It's true! Serious stress or sadness can cause your heart to give up. Chemicals like the stress hormone cortisol are incredibly bad for your heart's function. Your heart is so connected to your mind that after genetics and diet/exercise, your best protection against heart trouble is an active social life, ideally including a happy marriage.