Biological Molecules - You Are What You Eat: Crash Course Biology #3

Hank talks about the molecules that make up every living thing - carbohydrates, lipids, and proteins - and how we find them in our environment and in the food that we eat.

Want to find Crash Course elsewhere on the internet?

[honestleen]

He literally explained a two hour long lesson in 15 minutes im shook

[osiria]

Crash Course: "Helping Kids Cram For Their Exams Since Day One."

[francescakyanda]

Let me just say: God bless this brilliant man and his brother for teaching topics in 10-15 minutes that teachers needed weeks for. No offense teachers.

[psalmr]

Started watching this my freshman year in high school, now I'm watching them my freshman year in college.

[Mary-eoir]

I keep on getting med school ads on these bio videos and I'm like... Dude... I'm just tryna pass grade 10 calm down

[Propofol]

I remember watching this in Bio 1 back in 2017 as a first year bio major at 22 years old who finally decided he wanted to be a doctor after years of part time jobs and part time community college classes 😂, skip to January 2023 and I’m here casually reviewing as a first year med student 😂 cmon guys! You got this, there will be horrible days, good days, & great days.

Best of luck! ❤

PS- thank you crash course, thank you so much ❤❤❤

[alexandrapaige]

this helped me get an A on my thrid bio test. god bless hank green and the CC team

[animegirl]

Trying to test out of bio 101 so I can eventually get my third degree: NURSING (thanx Hank)
Along with that here is what I quickly typed down as a sort of SUMMARY, feel free to fix:

 William Prout discovered our stomachs have hydrochloric acid and discovered chemical composition of urea. Also discovered food is divided into carbs, fats, and proteins

 Carbohydrates are the source of all energy

 Carbs are made of sugars with the simplest being monosaccharides

 Glucose, a monosaccharide, number 1 sugar that comes from the sun

 Fructose, same chemical as glucose, but arranged differently, and is sweeter

 Disaccharides are two monosaccharides put together

 Sucrose, fructose and glucose connected, is a disaccharide joined by a covalent bond

 Polysaccharides are thousands of simple sugar units

 Cellulose is a bunch of glucose molecules

 Bread is made of starch and amylase

 Our bodies store carbs in form of glycogen in our muscle until we need to use them

 We store our energy long term through fat aka lipids

 Lipids are non polar and can’t dissolve in water

 Fats are made of glycerol and fatty acids

 Saturated fats don’t have double bonds, while unsaturated fats do

 Trans fat do not exist in nature and are unsaturated and bad for the body

 Omega 3 fats, unsaturated, are essential but we need to eat them in order to get them

 Phospholipids form cell membrane walls to keep bad stuff out and good stuff in

 Phospholipids are one end polar and one end non polar

 Steroids, a phospholipid made of 4 carbon rings, are used to make cholesterol

 Proteins of made of 20 amino acids which do everything for the body

 Nitrogen can only be gotten into our bodies from food, via foods high in protein

 Polypeptides are formed by long chains of amino acids

 The 9 essential amino acids, which are bodies can’t make on their own, are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine

[TheHunter]

I'm a computer scientist that migrated to bioinformatics and now I need to understand all this background in order to do my phd research, so yeah...you're not just helping high school people here but also researchers on a higher level. What you guys do is amazing. Thank you!

[yuhboi_ratmann]

"You are what you eat" .... I'm human.. *stares menacingly* 

[sarahholland]

have a test today and am watching this before i get ready for school. what would i do without you guys

[mikerust]

It has been eight years since this video was uploaded. I watched it for the first time about four or five years ago, when I was in high school. I prepared for the biology exam by these videos. I wathced this course when I was on the first year of medical university. And now I'm watching it again. I'm already finishing the third year and I teach biology scholars who, like myself some time ago, are about to enroll a med university. This is awesome. Thank you, Hank, and thanks to all of the CrashCourse team for this truly the greatest course of biology ever made.

[jaybird]

Watching every one of these videos for final exam tomorrow because my biology teacher sucks.

[fbi]

that mite on the Queen of England's eyelashes are no longer alive . . .

[loribenish]

Im almost 50 years old, and just passed all my prerequisites including A&P 1 and 2 and Microbiology. You have to pass the TEAS test to get into the program. Im here in March, 2020

[christinehakobyan]

This really helps! My teacher only lectures and she skips a lot because we "are already supposed to know it" and we are expected to know 10x the information she actually gives us.

[TheAshX]

This is the only way i'm passing college. Thank you.

[ashico]

Our biology teacher is lacking some serious teaching skills. Nearly EVERYONE in my class has stated that her methods of teaching are confusing. I keep telling fellow students to watch these crash course videos because they help me out A LOT! My teacher has heard me say this a few times. Once, after she spoke about cellular respiration, I said that crash course did a video on it that helped me understand all the parts involved. She shittily replied that if "colorful internet videos" where the only way we could learn, then maybe we should not be in her class. I don't think she likes me very well....

[youngphysists]

Who is watching this with me in the age of COVID 19?
And hello all who are learning this for learning and not passing your tests.☺🐤🐳

[katpricot]

Hank you're saving me on my Honors Bio exam tomorrow bless you ily