Flashcards
Gymnosperms
Flashcards do conjunto (49)
- 1What are the two major innovations that happened in seed plants? What factor did these innovations arise to combat?Seeds
Pollen
Lack of water - 2What does a seed contain?Embryo
Stored food
Seed coat - 3What does pollen contain?Microspore, in which a microgametophyte develops
- 4Where do the male and female gametophytes, respectively, develop in seed plants?Pollen/Seed
- 5Are gymnosperms heterosporous or homosporous?Heterosporous
- 6What is endosporic development?Gametophyte developing inside the spore
- 7Which generation is dominant in gymnosperms?Sporophyte
- 8Label this diagram.
- 9What are the advantages of having a seed?Protection of the embryo
Food storage is available - 10List the steps of the evolution of an ovule.1. Retention of megaspores within the megasporangium
2. Reduction to a single megaspore mother cell
3. Survival of a single megaspore following meiosis
4. Endosporic development of megagametophyte within the megasporangium
5. Formation of integument that completely envelopes the megasporangium except for a micropyle
6. Modification of the apex of the megasporangium to receive microspores or pollen grains - 11What is a micropyle?Small opening in the ovule to accept microspores/pollen
- 12What is pollen?Male gametophyte reduced to 2-4 cells that develops into the microspore wall (endospore)
- 13What is polinisationTransport of pollen to the ovule
- 14What is anemophily?Pollinisation by wind
- 15What is zoophily?Pollinisation by birds and mammals
- 16What is entomophily?Polinisation by insects
- 17What happens after pollination in Cycadophyta and Ginkophyta?Pollen tube grows in the nucellus like a parasite. When it is mature, it releases multi-flagellated sperm that swim to egg (needs water)
- 18What happens after pollination in Coniferophyta and Anthophyta?Pollen tube grows slowly to the archegonium and delivers sperm nuclei directly to the egg. No water is needed, sperm has no flagella and no antheridia are produced by the male gametophyte
- 19What are the phyla that comprise gymnosperms?Cycadophyta
Ginkophyta
Gnetophyta
Coniferophyta - 20When did Coniferophyta appear?In the carboniferous period
- 21What did Coniferophyta adapt to?Cold and dry climate
- 22What do the needles come out of in Coniferophyta?Fasicles
- 23What is a fasicle?Short shoot that has suspended apical meristem activity
- 24Why are needles good for dry conditions?Low surface area means less water loss. Also don't have many stomata.
- 25What anatomical part of Coniferophyta are strobili?Cones
- 26Are microsporangiate cones on Coniferophyta on superior or inferior branches?Inferior
- 27Are megasporangiate cones on Coniferophyta on superior or inferior branches?Superior
- 28What cells are microspores formed out of in Coniferophyta?2 Prothallalial cells
1 Generative cell
1 tube cell - 29Label this diagram
- 30What are the components of an ovuliferous scale?2 ovules and a subtending sterile bract
- 31What are the steps that happen before fertilisation in male cones in Coniferophyta?1. Microspore mother cells undergo meiosis to turn into pollen grain composed of a tetrad of microspores.
2. Pollen is liberated from microsporangia and carried by the wind
3. Pollen falls on pollination drop which is produced at the micropyle in the archegonia - 32What are the steps that happen before fertilisation in female cones in Coniferophyta?1. Megaspore mother cell undergoes meiosis to produce 4 megaspores
2. Megaspore turns into megagametophyte which is not released
3. Functional megaspore undergoes mitosis
4. Fertilization occurs - 33What happens after fertilization in Coniferophyta?1. Pollen tube grows and reaches archegonia
2. 2 sperm nuclei are released
3. 1 sperm nucleus fertilizes the egg, the other degenerates. - 34Which part of the seed is from the sporophyte generation? And the gametophyte generation?Sporophyte generation: Nucellus remnants and seed coat. Embryo
Gametophyte generation: Megagametophyte (storage tissue) - 35What do Cycadophyta look like?Palm trees
- 36How are Cycadophyta pollinated?Entomophily
- 37Can Cycadophyta symbiose with anything? If so, what?Yes
Cyanobacteria - 38What does dioecious mean?Plants are not hermaphroditic
- 39Where are the cones located in cycadophyta?At the end of stems
- 40Are Cycadophyta sperm flagellated or not?They are.
- 41Do Cycadophyta have wood?Yes
- 42What is the only species in Ginkophyta?Maidenhair Tree
- 43What are the characteristics of Ginkophyta?Large
Temperate
Deciduous
Dioecious
Fan-like leaves - 44What is unique about ginkophyta?Kiterpene Ginkolide that has medicinal uses
- 45Where does pollination happen in Ginkophyta?On the tree.
- 46Where does fertilization happen in Ginkophyta?On the ground
- 47What genera compose Gnetophyta?Ephedra
Welwitschia
Gnetum - 48What characteristics do Gnetophyta and angiophyta share?Some cones look like flowers
Tracheids AND vessel elements
No archegonia in Welwitschia and Gnetum - 49What is pseudo-double fertilization?When 2 sperm fertilize 2 eggs and make 2 embryos.
Informações
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- Gymnosperms flashcard set
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- Usuário eliminado · dez 2016
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- 9 dez 2016
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- Criado por Shareef Akbari · 8 dez 2016
- Copiado por Shareef Akbari · 8 dez 2016
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