According to the CDC, this is the minimum number of seconds you should scrub your hands with soap and water to remove germs effectively.
20 seconds
These are the three types of muscle tissue found in the human body.
skeletal, smooth, and cardiac
The American Dental Association recommends brushing your teeth this many times per day for two minutes each time.
twice
When a muscle does this — a fancy word for “tightening or shortening” — it pulls on a bone and creates movement.
contract, or contraction
The main job of sweating is NOT to make you smelly — it's to do this for your body when you get too hot.
cool you down
These tiny living things, found on every surface and even on your skin, are the main reason hygiene matters — and why washing your hands with soap helps prevent illness.
germs (or bacteria)
This type of muscle is attached to your bones and lets you move on purpose — walking, lifting, smiling, and writing all use this kind.
skeletal muscle
This natural mineral, found in most toothpastes and added to many community water supplies, helps strengthen tooth enamel and prevent cavities.
flouride
These tough, rope-like tissues connect your skeletal muscles to your bones. When the muscle contracts, these pull on the bone.
tendons
Surprise: sweat itself is mostly odorless. Body odor actually comes from these tiny living things on your skin breaking the sweat down.
bacteria
If soap and water aren't available, the CDC recommends using a hand sanitizer that contains at least this percentage of alcohol.
60%
This type of muscle is found ONLY in one organ in the body, where it works automatically to keep you alive 24/7.
cardiac muscle
This sticky, invisible film of bacteria builds up on your teeth every day. If you don’t brush or floss it off, it can harden and lead to cavities and gum disease.
plaque
These are the two muscles in your upper arm that work as an opposing pair: one bends your arm and the other straightens it.
This stage of life, which most 7th graders are going through right now, is when certain sweat glands switch on for the first time — which is why body odor becomes a new thing to manage.
puberty
Doing this daily activity — especially after sweating or playing sports — helps remove dead skin cells, dirt, and bacteria that build up on the body and contribute to body odor and acne.
showering (or bathing)
Smooth muscle is found in the walls of your stomach, intestines, and blood vessels. Unlike skeletal muscle, it does this — a key word that means “without your conscious control.”
involuntary
The ADA recommends replacing your toothbrush every three to four of these time periods, or sooner if the bristles are frayed or matted.
months
Skeletal muscles can only do this one action — they cannot push. That’s why they have to work in opposing pairs to move your bones in different directions.
pull, or contract
These two products are commonly used to manage underarm odor and wetness. One blocks sweat from coming out; the other masks or kills the bacteria that cause smell.
antiperspirant and deodorant
These three specific times are when handwashing is most important to prevent the spread of illness: before doing this, after doing this, and after coughing or sneezing.
before eating, after using the bathroom, and after coughing/sneezing
Skeletal and cardiac muscle both look striped under a microscope. This scientific term describes that striped appearance.
striated
This daily oral hygiene habit — done with a thin string — reaches the spaces between your teeth and along the gumline that a toothbrush cannot clean.
flossing
This is the muscle that rests inside your rear end.
gluteus maximus
This common skin condition, often connected with puberty, happens when oil and dead skin cells clog hair follicles and bacteria grow inside them. Washing your face daily can help reduce it.
acne or pimples