GCSE Biology - Cell Types and Cell Structure #2

00:06:49
https://www.youtube.com/watch?v=qHkUOlC8Nbo

Résumé

TLDRVideoen leverer en grundig intro til cellernes struktur og funktion, med fokus på forskelle og ligheder mellem dyre- og planteceller som eukaryote celler, og bakterieceller som prokaryote celler. Celler betragtes som de grundlæggende byggesten i alt liv, der kan replikere selvstændigt. Forskellige subcellulære strukturer eller organeller inden i cellerne, som cellemembran, kerne, cytoplasma, mitokondrier, ribosomer og i planteceller yderligere kloroplaster, cellevæg og vakuole, bliver forklarede. Bakterieceller har deres DNA frit flydende i cytoplasmaet og har unikke strukturer som plasmider og flagella til bevægelse. Videoen tilbyder også mere materiale og spørgsmål til videre studier.

A retenir

  • 🔬 Celler er livets grundlæggende byggesten.
  • 🌿 Planteceller har unikke strukturer som cellevæg og kloroplaster.
  • 🧬 Dyreceller og planteceller deler mange organeller som kerne og mitokondrier.
  • 🦠 Bakterieceller er prokaryote og simple i strukturen.
  • 🧪 Cytoplasma er stedet for mange kemiske reaktioner i cellen.
  • 🔋 Mitokondrier producerer energi gennem aerob respiration.
  • 🌱 Kloroplaster i planteceller er essentielle for fotosyntese.
  • 🧫 Bakterier kan have plasmider der giver særlige evner.
  • 📏 Celler kan replikere selvstændigt og vokse ind i multicyndellære organismer.
  • 🧿 Cellemembraner kontrollerer ind- og udsivning af stoffer.

Chronologie

  • 00:00:00 - 00:06:49

    I dagens video undersøger vi celler, herunder deres struktur og forskellene mellem dyre- og planteceller, samt bakterieceller. Celler er de mindste enheder, der kan reproducere sig selvstændigt, og vi finder dem i både encellede organismer som bakterier og flercellede organismer som dyr og planter. Videoen gennemgår cellens opbygning, herunder cellemembranen, kernen, cytoplasma, mitokondrier og ribosomer, som er fælles for både dyre- og planteceller. Planteceller har desuden en cellevæg, en permanent vakuole og kloroplaster, der er essentielle for fotosyntesen. Til sidst omtales bakterieceller, der er prokaryote med en enkelt cirkulær DNA-streng, ribosomer og cytoplasma, men uden mitokondrier eller kloroplaster. Nogle bakterier har også plasmider og flageller til bevægelse.

Carte mentale

Mind Map

Questions fréquemment posées

  • Hvad er celler?

    Celler er de mindste enheder af liv, der kan replikere uafhængigt.

  • Hvad er forskellen på dyre- og planteceller?

    Både dyre- og planteceller har cellemembran, kerne, cytoplasma, mitokondrier og ribosomer, men planteceller har yderligere cellevæg, vakuole og kloroplaster.

  • Hvordan adskiller bakterieceller sig fra dyre- og planteceller?

    Prokaryote celler, som bakterier, har ikke en kerne, mitokondrier eller kloroplaster. De har en cellemembran, cellevæg, ribosomer og cytoplasma, og deres DNA flyder frit.

  • Hvor findes kloroplaster og hvad er deres funktion?

    Kloroplaster findes i planteceller og er stedet, hvor fotosyntesen sker.

  • Hvad er mitokondriernes funktion i cellen?

    Mitokondrier nedbryder sukker for at frigive energi til cellen gennem aerob respiration.

  • Hvad er flagella?

    Flagella er tråd-lignende strukturer, der hjælper bakterier med at bevæge sig ved rotation.

Voir plus de résumés vidéo

Accédez instantanément à des résumés vidéo gratuits sur YouTube grâce à l'IA !
Sous-titres
en
Défilement automatique:
  • 00:00:00
    [Music]
  • 00:00:05
    in today's video we're looking at cells
  • 00:00:08
    so we're going to cover what cells are
  • 00:00:10
    and which subcellular structures they
  • 00:00:12
    contain
  • 00:00:14
    specifically though we're going to look
  • 00:00:16
    at the similarities and differences
  • 00:00:18
    between animal and plant cells first
  • 00:00:21
    which are both examples of eukaryotic
  • 00:00:23
    cells
  • 00:00:24
    and then also our bacterial cells which
  • 00:00:27
    are prokaryotic cells
  • 00:00:30
    so hopefully by the end of the video
  • 00:00:32
    you'll be able to label all the
  • 00:00:33
    different parts of a cell
  • 00:00:35
    and describe what each of them do
  • 00:00:40
    let's start with what cells are
  • 00:00:42
    you can think of cells as the basic
  • 00:00:45
    building blocks of life
  • 00:00:46
    and what we mean by this is that they're
  • 00:00:48
    the smallest unit of life that i can
  • 00:00:50
    replicate independently
  • 00:00:53
    so if we took an animal or a planter
  • 00:00:56
    they could divide into two cells then
  • 00:00:59
    into four cells and so on
  • 00:01:01
    in some cases though alike for bacteria
  • 00:01:04
    each individual cell is a whole organism
  • 00:01:08
    so when they divide like this they're
  • 00:01:10
    also reproducing
  • 00:01:11
    because every division produces a whole
  • 00:01:13
    new organism
  • 00:01:15
    animals and plants though are
  • 00:01:16
    multicellular which means that they
  • 00:01:18
    contain loads of cells
  • 00:01:21
    and so when their cells divide like this
  • 00:01:23
    they're normally just growing or
  • 00:01:25
    replacing dead cells
  • 00:01:26
    they're not normally making whole new
  • 00:01:28
    organisms
  • 00:01:32
    to see what i mean imagine we took a
  • 00:01:34
    human and looked at him closely under a
  • 00:01:36
    microscope
  • 00:01:38
    we'd see that he's made up of cells
  • 00:01:40
    so the skin contains skin cells the
  • 00:01:43
    blood contains blood cells and so on
  • 00:01:46
    in total we contain hundreds of
  • 00:01:48
    different types of cells
  • 00:01:50
    and is thought that an adult contains
  • 00:01:52
    over 40 trillion cells altogether
  • 00:01:57
    next we need to look at the actual
  • 00:01:59
    structure of cells
  • 00:02:01
    so we'll start by comparing an animal
  • 00:02:03
    cell and a plant side by side to
  • 00:02:05
    highlight their similarities and
  • 00:02:07
    differences
  • 00:02:08
    and then we'll look at bacterial cells
  • 00:02:10
    after
  • 00:02:11
    now to understand cell structure we need
  • 00:02:13
    to look at the different parts that make
  • 00:02:15
    up the cell
  • 00:02:16
    and these are known as subcellular
  • 00:02:19
    structures
  • 00:02:20
    or sometimes organelles
  • 00:02:23
    firstly both cells are surrounded by
  • 00:02:25
    these cell membranes that control which
  • 00:02:28
    substances can pass in and out of the
  • 00:02:30
    cell
  • 00:02:31
    for example they'll let some chemicals
  • 00:02:33
    through the membrane but not others
  • 00:02:36
    both types also have a nucleus which
  • 00:02:39
    contains the genetic material or dna of
  • 00:02:42
    the cell
  • 00:02:43
    and so it effectively controls the
  • 00:02:44
    activities of the cell as well
  • 00:02:47
    they're also both filled with a gel-like
  • 00:02:49
    substance called cytoplasm
  • 00:02:52
    this is what all the other sub-solar
  • 00:02:54
    structures sit in
  • 00:02:55
    and it's also where the chemical
  • 00:02:57
    reactions take place
  • 00:02:59
    you can basically think of it like water
  • 00:03:01
    filling a water balloon
  • 00:03:03
    but the consistency is closer to jelly
  • 00:03:07
    next they also have lots of mitochondria
  • 00:03:10
    whose job is to provide the cells with
  • 00:03:12
    the energy that they need to function
  • 00:03:14
    we'll cover how this works in another
  • 00:03:16
    video but basically they break down
  • 00:03:18
    sugars like glucose in a process called
  • 00:03:21
    aerobic respiration which releases
  • 00:03:23
    energy that the cell can use
  • 00:03:27
    and finally both cell types also contain
  • 00:03:30
    loads of ribosomes which are the site of
  • 00:03:32
    protein synthesis
  • 00:03:34
    which just means that it's where
  • 00:03:35
    proteins are made
  • 00:03:39
    now all of these sub-solar structures
  • 00:03:41
    that we've just mentioned are common to
  • 00:03:43
    both animal and plant cells but
  • 00:03:46
    importantly plant cells also have a few
  • 00:03:48
    extra structures
  • 00:03:50
    for one they have a rigid cell wall
  • 00:03:53
    around the entire cell
  • 00:03:54
    that's made up of material called
  • 00:03:56
    cellulose
  • 00:03:58
    and because cellulose is really strong
  • 00:04:00
    the cell wallet can provide support and
  • 00:04:02
    structure to the cell
  • 00:04:03
    which is really important because if too
  • 00:04:05
    much water enters the cell then it would
  • 00:04:07
    otherwise burst
  • 00:04:10
    next a lot of the cell is often taken up
  • 00:04:12
    with this thing called a permanent
  • 00:04:14
    vacuole
  • 00:04:16
    you can think of this as a big sac that
  • 00:04:18
    contains cell sap
  • 00:04:20
    which is basically a mixture of sugars
  • 00:04:23
    salts and water that this cell can use
  • 00:04:25
    when it needs to
  • 00:04:27
    and finally they also have chloroplasts
  • 00:04:30
    which is where photosynthesis happens
  • 00:04:33
    we cover in detail in another video but
  • 00:04:36
    basically photosynthesis is the process
  • 00:04:38
    by which plants use energy from the sun
  • 00:04:41
    to make sugars like glucose
  • 00:04:44
    and to help with this chloroplasts
  • 00:04:46
    contain a green substance called
  • 00:04:48
    chlorophyll which absorbs the light
  • 00:04:50
    energy that's needed for photosynthesis
  • 00:04:53
    and it's this chlorophyll substance that
  • 00:04:55
    makes plants leaves green
  • 00:05:00
    the last thing we need to look at are
  • 00:05:01
    bacterial cells
  • 00:05:03
    as we said earlier bacteria are
  • 00:05:05
    prokaryotes and consist of a single
  • 00:05:08
    prokaryotic cell this means we can refer
  • 00:05:11
    to them as unicellular which just means
  • 00:05:14
    a one cell organism
  • 00:05:17
    just like the eukaryotic cells that
  • 00:05:19
    we've seen so far bacteria also have a
  • 00:05:22
    cell membrane a cell wall
  • 00:05:24
    ribosomes and cytoplasm
  • 00:05:28
    importantly though they don't ever have
  • 00:05:30
    mitochondria or chloroplasts
  • 00:05:33
    and they don't keep their genetic
  • 00:05:34
    material in a nucleus
  • 00:05:37
    instead they have a single circular
  • 00:05:39
    strand of dna that's free to float
  • 00:05:41
    around the cytoplasm and that contains
  • 00:05:44
    all the genes that they need to survive
  • 00:05:46
    and reproduce
  • 00:05:48
    you might also see this labeled the
  • 00:05:50
    circular chromosome or nucleoid
  • 00:05:53
    but they all mean basically the same
  • 00:05:54
    thing it's just a big loop of dna
  • 00:05:58
    some bacteria also have additional small
  • 00:06:00
    rings of dna called plasmids
  • 00:06:03
    these carry extra genes like antibiotic
  • 00:06:05
    resistance which the bacteria don't need
  • 00:06:07
    on a daily basis but may sometimes come
  • 00:06:10
    in handy
  • 00:06:12
    some bacteria also have flagella
  • 00:06:15
    these are these thread-like structures
  • 00:06:16
    that have protrude out from the bacteria
  • 00:06:19
    and are able to rotate to propel the
  • 00:06:21
    bacteria along
  • 00:06:22
    so they basically allow the bacteria to
  • 00:06:24
    move around
  • 00:06:30
    anyway that's everything for this video
  • 00:06:32
    so i hope that was helpful for you if
  • 00:06:34
    you want to practice questions on this
  • 00:06:36
    or anything else in science or maths
  • 00:06:38
    then head over to our revision site
  • 00:06:40
    which you can access by pressing the
  • 00:06:42
    link in the top right corner of the
  • 00:06:43
    screen
  • 00:06:44
    otherwise have a fantastic day
Tags
  • celler
  • dyreceller
  • planteceller
  • bakterieceller
  • eukaryote
  • prokaryote
  • subcellulære strukturer
  • organeller
  • fotosyntese
  • aerob respiration