The Reproductive Lives of Nonvascular Plants: Alternation of Generations - Crash Course Biology #36
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- Опубликовано: 30 сен 2012
- Hank introduces us to nonvascular plants - liverworts, hornworts & mosses - which have bizarre features, kooky habits, and strange sex lives. Nonvascular plants inherited their reproductive cycle from algae, but have perfected it to the point where it is now used by all plants in one way or another and has even left traces in our own reproductive systems.
Table of Contents
1) Key Traits of Nonvascular Plants 01:42
2) 3 Phyla of Bryophytes 02:52
3) Alternation of Generations 04:33
a) Gametophyte Generation 05:04
b) Sporophyte Generation 05:25
c) In Vascular Plants 07:48
References:
news.nationalgeographic.com/ne...
kidsresearchexpress.blogspot.c...
facultyweb.wcjc.edu/biology/BI...
www.sumanasinc.com/webcontent/...
en.wikipedia.org/wiki/Alternat...
www.bio.miami.edu/dana/dox/alt...
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Can't stand at the fact that this was released 8 years ago.
Recommend you watch the whole video, but if you're in a rush to just get the idea of alternation of generations start at 4:50
You're my hero
You are correct! Added an annotation, thanks for letting me know. Not sure how that slipped through.
yes. yes. yes
It was such a wise decision to dump the lengthy textbook after 5 minutes to watch this!
So much easier to understand.
Thank You, Hank. Thank You.
The animation of mosses really helped me understand how mosses reproduce! I had 2 labs and a whole lecture over this and the 3 minute clip of this taught me more than the 3 hours I spend in lab and lecture. Many thanks!!
A small correction: The capsule holds 1000s of "haploid" spores, not "diploid". :) Loved the video! Great job with the animation!
My science teacher loves you and even assigned your videos as homework. She also likes to watch them in class. Nice videos, good job making them interesting and appealing to all ages. :)
They are great at that
So your science teacher is paid to teach you by showing you RUclips videos?
Damn. I’d be a great teacher in that case. I watch mostly sciency stuff that I could show kids... Wait... nope I don’t have the patience to deal with kids. Never mind.
Hank buddy, get me an A on my Bio test.
I believe in you more than I believe in myself.... I shouldn't have played BF4 all night >
pffttt it's all about advanced warfare now
psshhh destiny is life.
loccio il lupo well buddy that's your opinion and i respect it :)
tjtbkgaming lol get a character to lvl 20 and you'll be hooked...
loccio il lupo i played destiny a lot until aw came out i have a lvl 29 hunter, i stopped playing the day aw came out and haven't touched it since then.
no one expects the spanish moss
I really really really like this comment
At 7:13 I'm pretty sure he meant to say haploid spore not diploid because spores coming from the sporangium are 1n.
yup..u r right..well noted!
But spores have 2 sets of chromosomes...what am I missing?
H
It’s not an mistake they are diploid
They are 2N
You'll never know how happy I was to click on this review guide for part of my final to see my favorite SCI Show guy!! Instantly knew I was set. You da best!
I have to take a biology final tomorrow and, as I couldn't sleep, I'm reviewing. I have trouble retaining information due to my head fog, so I was happy to see an easier learning method than books and notes: these videos. Thank you for these. :)
Hank, at 7:15 you made a mistake by saying that the capsule is full of diploid spores. While the sporophyte is diploid, the spores produced should be haploid.
No. The gametaphytes release haploid cells which upon arrival at the archegonia join creating a diploid cell which replicates itself through mitosis until there are thousands of diploid cells (spores) which the calyptra releases and the ones that land on wet ground become bryophytes.
Ruadhan Glynn After fusion of the gametes in the archegonium, the newly formed diploid cells start replicating through mitosis (you're right uptil here) and form a sporophyte, the sporophyte then produces haploid spores through meiosis.
Demba Fofana Demba is correct. The spores couldn't possibly be 2n because they germinate on their own to create gametophytes which are n.
spores can be either haploid or diplod. Mitospores are haploid if made in haploid sporophyte or diploid if made on diploid sporophyte, meiospores are always haploid.
THANK YOU I WAS A BIT CONFUSED AT THAT POINT
this video got me an A on my biology exam
much thank
such hank
broooooooooo
Lil' Zombie Foo Foo Same
I feel like Crash Course should rightfully be sponsored by Google.
ariah johnson I don't care
ariah johnson I agree with you the ariah johnson
@@lichuo No one cares about the fact you don't care
they're sponsored by RUclips, which is a property of Google
megaKstudios I was so young when I wrote this lol I learned you can make money off of RUclips since then and I’m 21 now 🤣🤣🤣🤣🤣 whoops!
This is so amazing! As he was talking my thoughts actually started to align surrounding all the textbook stuff I've read - he makes it so easy to understand!!! :)
Thanks for wrapping this up for me! I have so much more understanding of all of this now!
These shows are fantastic. I love how you (Hank) and John present information. I hope you do more such as physics, because it is a misunderstood and a fun study.
After falling asleep through a few mono-toned lectures, this quick video really tied my understanding together, thank you.
I cant help but laugh!
So refreshing to see humor and quick explanations for what may seem like complicated topics! Wonderful videos. My son and I truly enjoy them (13 yrs old). As a future Science teacher it is something I will share and link to my pages, thank you!
Every video of yours I watch Hank I am just so grateful for, you make learning bio easy and straightforward, thank you!
Love this guy! Using his catalog of videos to teach our outdoor classroom in the Hamilton Gardens - good stuff!!!
Spanish moss is a plant,Tillandsia usneoides. We commonly refer to tillandsias as "air plants"...it is not a lichen.
yee
but i think at the time of making this video spanish moss was believed to be a lichen
You know what I love? The fact that these biology crash course videos are following my biology course at school down to the T. I've got a bio test on thursday that I need to revise for... was feel pretty annoyed about that, but then I realised it gives me an excuse to watch crashcourse! :D
Love the video! Was trying to review my knowledge of non-vascular plants and got a kick out of this while also accomplishing my goal. Thanks!
This could possibly be my favorite response I've read in a long time. Thank you for making my day.
so happy that i have this to help me study for my test tomorrow!
These are such great episodes!! Please keep it up!
Hey Hank, first of all, Thanks for all these great videos, they're helping a lot with the AP Bio test review. I have one question though, so if the gametophytes produce gametes through mitosis, how is genetic variation produced, how are gametes haploid, and how is gender detirmined? Thanks again for the videos!
Next week - don't miss Hank explaining how grass grows! He makes everything entertaining!!! Keep up the amazing work!
Hank, you actually just saved me for tomorrows test:) You are the best!!! Thank you soooooooooo much.
Great Video Series I'm learning lots, though it can be a lots of information at once so I really appreciate visual aids and Crashcourse's are great when there used. I have to add this one was confusing, there are comparison and cycles and different processes, it hard to keep it all straight. I watched parts four times now (which I learn something each time) but I'm still missing something.
This is so going to help me pass bio 2 lab and lecture I'm so happy !!!! 🤗
When Hank explained the concept of alternation of generations, I immediately understood it thanks to the Aliens franchise. Facehuggers are like sporophytes. Yay!
I know this video is old but I'd like to say that your channel has helped me so much through highschool. You make learning fun.
Thank you! This was extremely helpful
These videos are so amazing and Hank you are so funny! Thank you very much!
you are my only hope at doing well on my midterm today. thank you for being here haha
I just wanted to say thank you SO much Hank for Crash Course Biology, because of it I passed my end of term Biology test in the top 10% of the year group, when last year I was in the bottom 10%! SCIENCE, OH YEAH.
Hank you are doing a fine job
The examples of the ones that do not have a vascular system would be the liverworts, hornworts, and mosses but they have bizarre features for their reproduction systems but they need the requirement of water presented. They undergo gametophyte in which the sperm and egg meet and undergo mitosis then later releases spores into the air hoping it would fertilize another egg. - Great video!
This cleared up a cloud of confusion! Thanks a ton!
Thank you for this! I have an exam on this tomorrow.
Do you have any quick tips on remembering the life cycles of gymnosperms and angiosperms?
Shouldn't plant taxonomy use Divisons instead of Phyla?
Anyway you saved my morning, I didn't feel like studying for my Botany test, but this is a good compromise ;)
How can something that seems so complicated in lecture be explained in like 3 minutes. Thank you!
a long stalk with a cap on top called calyptra... beautifully helpful for remembering.
Yes I finally realized that after thinking about it for a while! Thanks :)
Thank goodness! Posted a day before our practicals and long tests *O* Thanks!
Literally just stepped out of my algae/moss lab in my bio class. THANKS HANK!!!!!!
so great. you've helped me more than you know! thanks!
Thank you. That one threw me through a loop, too.
Yeah thanks dude , with a lil back knowledge you helped me put this together
Awsome video! Thank you! so much for uploading.
thank you! This stuff is actually quite interesting
This was in my classroom today! I fangirled so much lmao
+Phoebe Smith I would too if I were in your place!
My guy explained something my bio teacher would have taken 4hrs to explain and made me understand with in 20 mins frrrr
I feel smarter everytime I watch one of these videos.
hey CC, at one point (5:41) you say the spores are haploid, and at (7:12) you say they are diploid. This is a pretty confusing topic so please fix. other than that, thank you sooo much for your collection of awesome videos! you're my hero!
+Gabriela Garcia The spores are actually haploids, in case you needed that. An easy way to remember it is how the fused gamete is diploid, so haploid spores are produced.
This is a good review for my IB Botany test for HL Bio.
this was a good one
Very informative
Hi! I wanted to know if nonvascular plants and vascular plants both had cuticles. I read on a few websites that they did have small waxy ones, but others say no. Thank you!
wow sir....ur videos r Vryy helpful....
Fascinating. The alternation of generations seems like a pretty effective strategy, combining the benefits of sexual reproduction (mutation) with the ease of asexual proliferation.
I told my Biology teacher about CrashCourse Biology and we might start watching them in class! Hooray!
thank you so much crash course! midterm in four hours ; ^ ;
Nice video although at 7:21 you say that you need high humidity levels for spore release whereas dry conditions are actually needed ;)
Thank you sooo much, you've just saved my biology test ^.^
Thank you from me as well, Hank. Will be sad to see this end in four weeks. Would be excellent if you two could start a new series, but since this is offered to us for free? I have absolutely no right to complain if you don't.
Good job!
This is amazing!
You've probably already realized this, but Crash Course puts out about one video a week on each active course. Biology and Ecology have ended and Hank is working on Chemistry now. (You can find the playlists at the Crashcourse page.) His brother, John, has finished World History and Literature, and is working on US HIstory. All the courses are worth watching. Have fun learning!
such a good teacher!!! random.. but i love the wanted!
I swear Hank shows up in almost every science RUclips channel I visit.
Do you think you could (at some point) do a video on plants that seem to be geared entirely on very rapid reproduction and choking out all other plants? We have some non-native species on the Eglin Reserve that are very interesting and do this. They're generally a problem for the forest, as well as controlled burning (since they ignite like gasoline during fires).
Thanks. Took my AP test today- NOTHING about ecology 90% of it was just graphs- and I saw EVERY video.
Instead of relying on my ancient textbook to do my independent study unit, I can come here and not be bored to death. Thanks for making it interesting, Hank! :D
unexpected slide whistles make everything better
That was pretty cool! Thanks.
Writing my bio final today thanks for the help crash corse
Such pretty scenery.
decomposer is normally a term used in relation to a wide range of organisms that break down organic matter as I'm sure you are aware, the partner in the litchen is in fact a photo-, or more often, a chemoautotroph.
Very Good Video's!
6:07 is where it's at. Turn on the captions if necessary.
I was looking for a way to procrastinate since this is the lazy person I am.Then I stumbled upon this gem here and voil´a!I can actually revise for my botany exam while kind of relaxing my brain at the same time!
Thanks for bringing romance to the scientific process! =D
Hank! Why weren't you making these 20 years ago? Never mind, silly question. However I would have been inspired to pursue Biology (in more ways than the usual one, heh). You and your brother are brilliant presenters and teachers.
7:12 he means HAPLOID spores!!!!!!!!!!!! confusing but actually helped me learn it from getting confused and figuring it out
I literally have an exam on this tomorrow oh my god, thanks Hank!
Love this just like all of the rest! Just found a tiny edit...can you put a word blip that says "haploid" in, where you talk about spores? The sporangium is diploid, but the spores, produced via meiosis, are haploid, not diploid. I'm sure it was just a verbal slip - bound to happen!
This is great!
I am wondering if there is an error in this video - at 7:14 he says that the capsule is full of "diploid spores" - but aren't the spores haploid since they then go on to become a gametophyte?
"The mosses... Mmmm, fuzzy."
n_n
Yes!! It's learning time!
never covered plants in my bio class so i gotta learn this for DAT
Depends on what taxonomist you ask. Bryophyta, Anthocerophyta and Hepatophyta are all recognized as phyla or have been at some point. But yeah, unranked divisions are more common in botanical taxonomy these days.
Yup. Are you gonna be ok?
my god, you're so fabulous. Thank you so so so much for this.
2019?????And btw i have an exam tomorrow
The capsule on the bryophyte sporophyte will release it's spores when humidity levels are LOW, not high. When the air is dry, spores may be dispersed more widely and over greater distances than when the air is wet.