Understanding Stem Cells: Embryonic, Adult, and Plant Stem Cells Explained

in this video we're looking at stem cells so we're going to explain what they are and why they're so important

and then take a closer look at some examples namely embryonic stem cells and adult

stem cells which are found in animals and then plant stem cells which are found in merry stem tissue in plants

let's start with what stem cells are and there are really two key features that you need to know

the first is that stem cells are able to divide by mitosis to form more cells so one can divide into two then they can

divide into four and so on the second is that stem cells are able to differentiate into specialized cells

so one stem cell could differentiate into a specialized nerve cell for example

whilst another could differentiate into a skin cell to understand why this is important

let's consider how human life starts when a sperm cell fertilizes an egg cell it forms a single cell called a zygote

this cell is now its own organism and during the following few days it will divide by mitosis over and over again to

form a small group of cells called an embryo we call these cells embryonic stem cells

and importantly these ones can differentiate into absolutely any type of cell

for example a nerve cell skin cell or blood cell over time these cells continue to divide

and also differentiate into all of the other important cells that we need and after nine months or so we end up

with a baby now if we fast forward a bit to an adult there are no longer stem cells that can

differentiate into absolutely anything like the embryonic stem cells can instead we have other types of stem

cells that have already specialized a bit meaning that they can now only differentiate into a narrow range of

cells for example in the middle of some large bones there's a jelly-like substance

called bone marrow which contains adult stem cells these cells can divide by mitosis as much as they like

but they can only differentiate into different types of blood cells like red blood cells white blood cells or

platelets the idea with stem cells like this is that they can replace damaged cells to

keep us alive but they don't form any new tissues like the embryonic stem cells did

now the last thing we need to cover are plant stem cells plant stem cells are found in plant

tissues called merry stems which are found in areas of the plant that are continually growing

like the very tips of the roots and shoots as the plant grows these unspecialized

stem cells will differentiate into all of the cells and tissues that the plant needs

like the palisade cells that do photosynthesis phloem and xylem cells that transport

sugars and water or root hair cells that absorb water and mineral lines

importantly plant stem cells persist for the plant's entire life unlike embryonic stem cells which

disappear by the time we're fully developed hey everyone amadeus here i just wanted

to let you know that we also have a learning platform where you can watch all of our videos

practice what you've learned with questions and keep track of all of your progress

for both the sciences and maths it's completely free so if you haven't already you can check it out by clicking

on our logo here on the right or if you'd like to do the lesson for this particular video we put the link to

that in the description down below we've also arranged all the videos for this subject in a playlist for you here

that's all though so hope you enjoy and i'll see you next time thanks