Inside The Living Body Notes

It takes 40 weeks for a fetus to develop from a single cell into an organism DNA is unique to every person The first thing a baby must do when it is born is breath The ADRENAL glands send adrenaline around the body The air sacs where gas exchange occurs in the lungs are called alveoli. The heart is the size of a walnut on the first day of life. The digestive tract must clear itself out on the first day of life to prepare for its first meal. The bowels must clear out the sticky tar-like substance called meconium. 100 thousand billion cells make us who we are and builds our body The first of seven hundred million breaths are the most important in life The alveoli are millions of tiny air sacks in our lungs and pull out the C02 from our lungs The first hour brings rapid change in order for the body to adapt outside the home At one year the hearts is no bigger than a walnut and is at its most delicate The digestive track it filled with meconium and is extracted for the real food to enter It was a hundred degrees in the home and anything colder is a shock to the system The feeling of extreme cold is felt in the deep part of our brain called the hypothalamus A layer of tissue around the organs keeps us warm and heats the internal organs (fat) The mother's milk protects us from hidden danger because outside there is bacteria everywhere and our skin is under constant attack from it The immune systems aren't developed yet so they can't fight them against themselves The mother develops antibodies to fight the bacteria and is transferred in their milk At 1 month the nose works overtime and the nerves inside detect chemicals The hearing in the ear vibrates throughout the body and the smallest bones in our body are held in them and without them we wouldn't be able to hear We are born with very underdeveloped vision and mostly black and white The eye muscles are immature which keeps is from pointing them where we want to The lens muscle still can't focus and flips the images we see and send it to the brain At 2 months we can distinguish colors and shades and at 4 notice the moms face At 6 months we have 20/20 visions and as well a growth spirts along with the eyes At 8 months all our senses work including the one we use most which is touch There are 9 thousand sensors on the tongue alone, that's why babies use it Digestion starts in the mouth, teeth grind it and the glands pump out saliva The smaller intestines are where we collect most of the nutrients, we eat The valve that is at the end of the long intestines keep from the food from going back 12 months and the baby is mobile and has perfected the art of crawling At the birth the skeleton is mostly cartilage, same as our ears, but it is flexible At birth we have gapes in the skill to let the brain deform and then they close The key to standing is hidden deep in our ears, 3 loops in our ears tell us up and down They spurt fluid and they slosh against the sensory tubes and gives us direction of movement and they are our organs of balance Our saliva glands are tiny but produce half a gallon of salvia every day The fever that comes with infection is a sign that the body is fighting back the sickness In the immune system the white blood cells latch onto the affected cell and kill it If we catch the same disease when we are older than the antibodies recognize it and kill it By age 11 puberty is already underway for most. It depends on our DNA clocks It all begins in the brain, at the hypothalamus, where it controls our body temp. The hypothalamus releases a protein and this is the start of puberty and a chain reaction The ovaries not only produce eggs but also a bunch of chemicals like hormones The hormones in the physical characteristics of manhood is the testosterone