Podcast
Questions and Answers
During pollen germination, which layer of the pollen grain wall emerges to form the pollen tube?
During pollen germination, which layer of the pollen grain wall emerges to form the pollen tube?
- Neither exine nor intine directly contributes to the pollen tube.
- Intine after the exine ruptures at the germ pore. (correct)
- Exine, due to its thick and ornamented structure.
- Both exine and intine emerge simultaneously.
Which statement accurately describes the nuclear composition of the pollen tube during germination?
Which statement accurately describes the nuclear composition of the pollen tube during germination?
- It contains a single, haploid generative nucleus which directs tube growth.
- It contains only the tube nucleus, as the generative nucleus degenerates early in the process.
- It contains two identical nuclei responsible for cell division.
- It contains two nuclei of different sizes: a larger tube nucleus and a smaller generative nucleus. (correct)
If a pollen grain's exine layer failed to rupture, what would be the most likely consequence?
If a pollen grain's exine layer failed to rupture, what would be the most likely consequence?
- Pollen tube formation would be inhibited, preventing fertilization. (correct)
- The intine would still emerge successfully, forming a normal pollen tube.
- The generative nucleus would divide within the pollen grain itself.
- The pollen grain would germinate prematurely, releasing its contents.
Considering the structural properties of the pollen grain wall, which of the following is most accurate regarding its function?
Considering the structural properties of the pollen grain wall, which of the following is most accurate regarding its function?
How does the haploid nature of pollen grains relate to their role in plant reproduction?
How does the haploid nature of pollen grains relate to their role in plant reproduction?
Flashcards
Pollen Germination
Pollen Germination
The process where pollen grains develop and grow into pollen tubes.
Pollen Grain Structure
Pollen Grain Structure
Pollen grains are unicellular and haploid with a bilayered wall (exine and intine).
Exine
Exine
The thick and ornamented outer layer of a pollen grain.
Intine
Intine
Signup and view all the flashcards
Pollen Tube Nuclei
Pollen Tube Nuclei
Signup and view all the flashcards
Study Notes
Germination of Pollen Grains
- Objective: To study pollen germination on a slide
- Requirements: Pollen grains from available flowers (e.g., Lilium, Antirrhinum, Catharanthus roseus), a cavity slide
- Comments:
- This slide shows germinating pollen grains in various stages
- Pollen grains are unicellular and haploid
- Pollen grains have a bilayered wall: an outer exine and an inner intine
- The exine is thick and ornamented
- The intine is thin and soft
- In some pollen grains, the exine has broken, and the intine extends outside forming a pollen tube
- The pollen tube's protoplast contains two nuclei:
- A larger nucleus, known as the tube nucleus
- A smaller nucleus, known as the generative nucleus
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Observe pollen germination on a slide using pollen grains from flowers like Lilium. Note the bilayered wall (exine and intine) and pollen tube formation. Identify the tube nucleus and generative nucleus within the pollen tube's protoplast.
