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Generatiewisseling: verschil tussen versies

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→‎Dominante gametofyt: schema's vervangen
Regel 56:
 
Schema van de levenscyclus:
{|class="toccolours" cellspacing="0" width=100% style="text-align:center;font-size:90%;line-height:90%;"
| style="text-align:left;"| 2n = diploïde fase
| → zygote (2n) → {groei} → sporofyt met [[Sporangium|sporangia]] (2n) → {meiose} →
|-
!colspan=18|Generatiewisseling: digenetische cyclus<br>Kernfasewisseling: diplohaplofasische cyclus met sporische (intermediaire) meiose
| style="text-align:left;"| n = haploïde fase
|-style="background-color:#EEEEEE;"
| → spore (n) → {groei} → [[Voorkiem|protonema]] → {groei} → '''gametofyt''' met [[Antheridium|♂]] en [[Archegonium|♀ gametangia]] (n) → {mitose} → ♂ en ♀ gameten (n) → {bevruchting} →
|-colspan=18 style="text-align:left;"|{{aut|eenhuizige, isosporangiate, isospore diplohaplont met dominante gametofyt}}
|colspan=2 style="border-top:solid windowtext 1.0pt" |waarin: ♂ = mannelijk; ♀ = vrouwelijk
|}
 
De [[mossen]] zijn gewoonlijk een eenhuizige, isosporangiate, isospore diplohaplont, en zijn slechts zelden tweehuizig en heterospoor. De gametofyt is dominant en de sporofyt parasiteert op de gametofyt. ''[[Buxbaumia]]'' ([[kaboutermos]]) heeft echter een gametofyt die betrekkelijk snel afsterft, zodat de groene sporofyt een tijdje zelfstandig leeft tot aan de sporerijping.
{|cellspacing="0" bgcolor="Palegreen" style="text-align:center;border-collapse:collapse;font-size:90%;line-height:90%;"
|Diplohaplont
|'''[[gametofyt]]'''<br />dominant
|''[[isosporie]]''
|-
| style='border-right:double windowtext 2.5pt'|
| style='border-top:double;border-bottom:double windowtext 2.5pt; border-right:double windowtext 2.5pt' bgcolor="Pink"| [[zygote]]
|
|-
|
| style='border-bottom:double windowtext 2.5pt'| ↓''groei''
|
|-
| style='border-right:double windowtext 2.5pt'|
| style='border-bottom:solid windowtext 1.0pt; border-right:double windowtext 2.5pt' bgcolor="Pink" | [[embryo]]
|
|-
| style='border-right:double windowtext 2.5pt'|
| style='border-bottom:double windowtext 2.5pt; border-right:double windowtext 2.5pt' bgcolor="Pink"| [[Sporangium|sporendoosje]]
|
|-
|
| style='border-bottom:solid windowtext 1.0pt'| '''[[Meiose|Reductie'''↓'''deling]]!'''
|
|-
| style='border-right:solid windowtext 1.0pt'|
| style='border-bottom:solid windowtext 1.0pt; border-right:solid windowtext 1.0pt' bgcolor="Lightcyan"| ''[[spore]]''
|
|-
|
| style='border-bottom:solid windowtext 1.0pt'| ↓''groei''
|
|-
| style='border-right:solid windowtext 1.0pt'|
| style='border-bottom:solid windowtext 1.0pt; border-right:solid windowtext 1.0pt' bgcolor="Lightcyan"| [[voorkiem]]
|
|-
| style='border-bottom:solid windowtext 1.0pt'|
| style='border-bottom:solid windowtext 1.0pt'| ↓''groei''
| style='border-bottom:solid windowtext 1.0pt'|
|-
| style='border-left:solid windowtext 1.0pt; border-bottom:solid windowtext 1.0pt;background:lightcyan' |
| bgcolor="Lightcyan"| '''[[Mossen|Mosplant]]'''
| style='border-bottom:solid windowtext 1.0pt; border-right:solid windowtext 1.0pt' bgcolor="Lightcyan" |
|-
| style='border:solid windowtext 1.0pt; background:lightcyan'| [[antheridium]]
| style='border-bottom:solid windowtext 1.0pt; border-right:solid windowtext 1.0pt' bgcolor="Lightcyan"|
| style='border-bottom:solid windowtext 1.0pt; border-right:solid windowtext 1.0pt' bgcolor="Lightcyan"| [[archegonium]]
|-
| style='border-bottom:solid windowtext 1.0pt'| ↓
|
| style='border-bottom:solid windowtext 1.0pt'| ↓
|-
|rowspan=2|→
| style='border:solid windowtext 1.0pt' bgcolor="Lightcyan"| ''[[zaadcel]]''
|rowspan=2 style="background-color:Lightcyan;border-bottom:double windowtext 2.5pt;border-right:double windowtext 2.5pt;border-top:double windowtext 2.5pt;border-left:double windowtext 2.5pt;"|zygote<br>(2n)
| style='border-right:solid windowtext 1.0pt'|
|rowspan=2 colspan=6|→ groei →
| style='border-bottom:solid windowtext 1.0pt; border-right:solid windowtext 1.0pt' bgcolor="Lightcyan"| ''[[eicel]]''
|rowspan=2 style="background-color:Lightcyan;border-bottom:double windowtext 2.5pt;border-right:solid windowtext 1.0pt;border-top:double windowtext 2.5pt;border-left:double windowtext 2.5pt;"|sporofyt
|rowspan=2 style="background-color:Lightcyan;border-bottom:double windowtext 2.5pt;border-right:double windowtext 2.5pt;border-top:double windowtext 2.5pt;"|sporangium<br><small>=sporenkapsel</small>
|rowspan=2|→ meiose →
|rowspan=2 style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|spore (n)
|rowspan=2|→ groei →<br><small>via protonema</small>
|rowspan=2 style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|'''gametofyt'''
|style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;"|♂ gametangium
|→ deling →
|style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|♂ gameet
|rowspan=2|&nbsp;> bevruchting →
|-
|style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;"|♀ gametangium
|align=right | ↓
|→ deling →
|
|style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|♀ gameet
|↓
|-style="background-color:#EEEEEE;"
|colspan=18 style="text-align:left;"|{{aut|eenhuizige, isosporangiate, heterospore diplohaplont met dominante gametofyt}}
|-
|rowspan=2|→
|
|rowspan=2 style="background-color:Lightcyan;border-bottom:double windowtext 2.5pt;border-right:double windowtext 2.5pt;border-top:double windowtext 2.5pt;border-left:double windowtext 2.5pt;"|zygote<br>(2n)
|→&nbsp;'''[[Bevruchting]]'''&nbsp;←
|rowspan=2 colspan=6|→ groei →
|
|rowspan=2 style="background-color:Lightcyan;border-bottom:double windowtext 2.5pt;border-right:solid windowtext 1.0pt;border-top:double windowtext 2.5pt;border-left:double windowtext 2.5pt;"|sporofyt
|rowspan=2 style="background-color:Lightcyan;border-bottom:double windowtext 2.5pt;border-right:double windowtext 2.5pt;border-top:double windowtext 2.5pt;"|sporangium
|rowspan=2 |→ meiose →<
|style="background-color:Pink;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|♂ spore (n)
|→ groei →
|style="background-color:Pink;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|'''♂ gametofyt'''
|style="background-color:Pink;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;"|♂ gametangium
|→ deling →
|style="background-color:Pink;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|♂ gameet
|rowspan=2 |&nbsp;> bevruchting →
|-
|style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|♀ spore (n)
|
|→ groei →
| style='border-bottom:double windowtext 2.5pt'| ↓
|style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;border-left:solid windowtext 1.0pt;"|'''♀ gametofyt'''
|
|style="background-color:Pink;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;border-top:solid windowtext 1.0pt;"|♀ gametangium
|-
|→ deling →
| style='border-right:double windowtext 2.5pt'|
| style='"background-color:Pink;border-bottom:doublesolid windowtext 21.5pt0pt; border-right:doublesolid windowtext 21.5pt'0pt;border-top:solid bgcolor="Pinkwindowtext 1.0pt;border-left:solid windowtext 1.0pt;"|♀ [[zygote]]gameet
|
|-
|
|&nbsp;
|
|}
 
De [[mossen]] zijn gewoonlijk een eenhuizige, isosporangiate, isospore diplohaplont, en zijn slechts zelden tweehuizig en heterospoor. De gametofyt is dominant en de sporofyt parasiteert op de gametofyt. ''[[Buxbaumia]]'' ([[kaboutermos]]) heeft echter een gametofyt die betrekkelijk snel afsterft, zodat de groene sporofyt een tijdje zelfstandig leeft tot aan de sporerijping.
 
=== Dominante sporofyt ===
Overgenomen van "https://nl.wikipedia.org/wiki/Generatiewisseling"