Look Who's Talking: Crash Course Kids #27.2 - Free Educational videos for Students in K-12

Look Who's Talking: Crash Course Kids #27.2 - By Crash Course Kids

Transcript


00:09	humans absolutely depend on plants . I mean , they
00:12	provide a lot of the oxygen that we breathe .
00:14	They're a huge part of our diet and they sure
00:16	do brighten up a room . I say we should
00:18	thank them . Thank you . Thank you friends .
00:22	It's too bad that plants don't talk because I have
00:24	a lot of questions for them and you just don't
00:26	find too many ants around . But humans do know
00:29	a whole lot about plants . We know what resources
00:31	they need to stay alive and how they make energy
00:34	through photosynthesis and plants didn't tell us these things .
00:38	So how do we study plants ? You already know
00:45	how scientists try and answer questions about the world around
00:48	us . After all , as scientists ourselves , we've
00:51	done activities to answer questions about plants . Like how
00:54	do plants change light energy into chemical energy and do
00:57	plants really need dirt to grow ? Each time we
01:00	ask the question , we followed it with an investigation
01:03	a sort of exercise to try and find an answer
01:05	to that question . Scientists do a lot of investigations
01:08	about plants and usually they follow the same general set
01:11	of steps . You probably already realized that investigations start
01:15	with a question and scientists sometimes have a pretty good
01:18	guess about what the answer to that question might be
01:21	, but I guess isn't good enough . So they
01:23	design an investigation to see if their guests is right
01:25	. Investigations can be complicated experiments or they can be
01:29	based on simple observation . Then scientists look at the
01:32	results of their investigations for evidence and then decide if
01:36	the evidence supports their guests or not . Sometimes they
01:39	don't find an answer to their question at all ,
01:41	in which case it's back to the drawing board ,
01:44	but sometimes they do . For example , some scientists
01:47	study special carnivorous plants like the funky venus flytrap .
01:51	This plant nashes on insects as part of its diet
01:53	, closing its leaves when it feels an insect walking
01:55	over it . But a few scientists noticed that a
01:57	fly traps leaves will close when an insect walked over
02:00	them , but not when rain falls on them .
02:03	What's up with that ? So the scientists basically said
02:06	investigation challenge accepted . It began with that basic question
02:10	. How does the venus flytrap feel insects on its
02:13	leaves ? Each scientists designed their own investigation and looked
02:16	at the results for evidence and like all good mature
02:19	humans scientists share . So they shared the results with
02:22	each other and working together , learned an answer to
02:24	their questions . They discovered that their hairs inside each
02:27	venus flytrap leaf and these hairs have to be jiggled
02:30	a few times in a row so that the lethal
02:32	close a score me insect will cause the leaf to
02:34	close a drop of rain . Not so much .
02:36	Ding question answered . Now , I wonder if we
02:39	could do our own investigation about a plant . Since
02:42	we know that plants need sunlight for photosynthesis , you
02:45	may have noticed that plants growing on a windowsill bend
02:47	toward the light , which is cool , But how
02:49	do they do it ? A scientist named Charles Darwin
02:52	asked this exact question and did an investigation of his
02:55	own in an attempt to answer it . It went
02:57	down a little , something like this . Darwin gets
03:03	that there was something in the tip of a plant
03:05	stem that helped its sense where the light was coming
03:07	from . So he designed an experiment to see if
03:09	he was right . He grew plants all the same
03:11	type and gave them all the same amount of light
03:14	and water . He left one plant alone . He
03:16	cut the tip from another . He covered the tip
03:18	of one plant with a little glass cap . He
03:20	covered the tip of another with a dark cap and
03:22	he covered the middle part of another plant with a
03:25	dark piece of material . He observed that as the
03:27	plants grew , the ones that had no tip in
03:29	the one that had the dark cap didn't grow towards
03:31	the light . So he concluded that the evidence showed
03:34	he was right about the plant stem tips sensing the
03:37	light , investigations for the wind . Because of studies
03:44	like this , it may seem like we know a
03:45	lot about plants . But believe me , people ,
03:47	there are even more things we don't know about them
03:50	. For one thing , scientists know that plants can
03:52	communicate with one another , but don't know all the
03:54	ways how . And scientists are always trying to figure
03:56	out how to stop disease implants , especially in the
03:58	ones we eat . So scientists do activities called investigations
04:02	that try and answer questions . Many of the investigations
04:05	they've done helped us to learn a lot about plants
04:07	, including how they can sense the world around them
04:09	and who knows what other investigations might discover some day
04:12	. So get out there scientists and start investigating ,
04:15	but not on your family's house plants . They probably
04:18	want those to stay the way they are .

Summarizer

DESCRIPTION:

OVERVIEW:

Look Who's Talking: Crash Course Kids #27.2 is a free educational video by Crash Course Kids.

This page not only allows students and teachers view Look Who's Talking: Crash Course Kids #27.2 videos but also find engaging Sample Questions, Apps, Pins, Worksheets, Books related to the following topics.