Plants
Explain the Alternation of Generations Life Cycle in plants. Include in your description terms
such as sporophyte, gametophyte, haploid, diploid, mitosis, meiosis, spore, fertilization and
zygote.
Alternation of generations is a life cycle which includes two very different stages where the organism eventiuallt changes into. The two stages exhibit different structure and functions. In plants, the two alternative stages is the gameotophyte stage and the sporosphyte stage. The gameotophyte stage is a haploid which produces gametes. The gametes then continue on to come into contact (sperm meets egg) and fertilize. The fertilized egg, called a zygote then goes trhough mitosis to create the sporophyte stage. The sporophyte is the diploid stage (2n) which releases male and female parts. They then go through meiosis and now are in the haploid stage (n) gameotophyte.
2. Describe the characteristics of the following classifications of plants:
a. Bryophyta – mosses, liverworts, hornworts. –non vascular, gameotophyte dominant, waxy cuticle, protected embyros, utilize air for reproduction, swimming sperm, spore for reproduction
b. Pteridophyta – ferns- seedless, sporophyte dominant, vascular, swimming sperm (wet environment for reproduction), spores for reproduction
c. Gymnosperm –evergreens- seeds, pollen, can live in dry conditions, sporophyte dominant, vascular, true root, wind reproduction, needles as leaves
d. Angiosperm -
3. Compare the life cycles of the above four classifications of plants. You may choose to include
pictures from the web as long as you explain the process.
The life cycles of all plants exhibit an alternations of generations which show a gametophyte and sporophyte generation
Bryophyta- Gameotophyte (n) dominant, sporophyte used for species dispersal. A mature gameotophyte, either male or female, have a reproductive structure. Archegonium is the female structure which houses the eggs, while the antheridium is the male structure which contains all the sperms. The sperm travels from the antheridum to the archegonium with moisture and fertilizes. The newly formed zygote goes trhough mitosos until it is a sporophyte (2n). The sporophyte generation is dependent and attached to the gameotophyte. Then when it is fully developed the capsule on top release spores (hapliods n) into the envroment until it germinates in soil, where then develops into a gameotophyte.
Pteridophyta- Ferns- Sporophyte dominant, gameotphayte called prothallus and used only to produce gametes. The sporophyte is diploid (2n) and multicellular and when ready to reproduce goes trhough meisos to create haploid spores. The go through mitosis until they are a gameotophyte (n), which continures mitosis until they have gametes, which then fertilize to become a diploid (2n) zygote, which then again goes through mitosos until it’s a full sporophyte.
Gymnosperms- evergreens, confiers- Sporophyte dominant, gameotophyte used for gamete production. The sporophyte, which is the full fledged tree, produces male and female parts called a seed cone (female) and pollen cone (Male). Their sprocytesilize s to then go thorugh meiosis until they are gameotophytes. The two gendered gametphyte, male being a pollen grain (contains the sperm) and female being the eggs in the archegonium, then meet trhough wind pollination. It takes a large time period to fertilize ince the pollen grains must produce a pollen tube to reach the eggs. Once fertilized, the diploid zygote undergoes mitosis until it is a seed, which then continues to go under mitosis until it’s a tree. Then the cycle repeats.
Angiosperms- flowering plants- Sporophyte dominant, gameotphytes for gamete production. The sporophyre, which lives as many things in this cycle. It begins as a flower, which conatins all the reproductive organs, then meiosis is quick while the male gametes are pollinated into the pollen tubes where they travel down to the eggs. Then when fertilized, mitosis kicks in and may become a fruit, which conatins seeds to be dispributed by animals etc. Then the seed germinates and grows into the flower, where the cycle repeats.
4. Describe the organization of an angiosperm including the functions of each part you describe.
The angiosperm, or flowering plant, is composed of many structur In the basic body overview, you se the basics, roots, stem, leafs and flowers. In the flower you can see all the reproductive structures.
The leafs-used for attracting pollinators, and photosynthesis
The sepal- support and protection
Carpel-female structures
1. Stigma- the sticky top which catches pollen
2. Style- the long tube which the sperm travels down to reach the eggs
3. Ovary- The surrounding structure which encases the ovules/ eggs
4. Ovule- The casing which conatisn th female gamres (eggs)
Stamen- the male structures
1. Anther- the bussel of pollen which is picked uip or sperm for fertilization
2. Filament- the strural support which holds up and etend the anther
5. Your drawings of the slides from the Algae, Bryophytes and Pteridophytes microscope lab.
such as sporophyte, gametophyte, haploid, diploid, mitosis, meiosis, spore, fertilization and
zygote.
Alternation of generations is a life cycle which includes two very different stages where the organism eventiuallt changes into. The two stages exhibit different structure and functions. In plants, the two alternative stages is the gameotophyte stage and the sporosphyte stage. The gameotophyte stage is a haploid which produces gametes. The gametes then continue on to come into contact (sperm meets egg) and fertilize. The fertilized egg, called a zygote then goes trhough mitosis to create the sporophyte stage. The sporophyte is the diploid stage (2n) which releases male and female parts. They then go through meiosis and now are in the haploid stage (n) gameotophyte.
2. Describe the characteristics of the following classifications of plants:
a. Bryophyta – mosses, liverworts, hornworts. –non vascular, gameotophyte dominant, waxy cuticle, protected embyros, utilize air for reproduction, swimming sperm, spore for reproduction
b. Pteridophyta – ferns- seedless, sporophyte dominant, vascular, swimming sperm (wet environment for reproduction), spores for reproduction
c. Gymnosperm –evergreens- seeds, pollen, can live in dry conditions, sporophyte dominant, vascular, true root, wind reproduction, needles as leaves
d. Angiosperm -
3. Compare the life cycles of the above four classifications of plants. You may choose to include
pictures from the web as long as you explain the process.
The life cycles of all plants exhibit an alternations of generations which show a gametophyte and sporophyte generation
Bryophyta- Gameotophyte (n) dominant, sporophyte used for species dispersal. A mature gameotophyte, either male or female, have a reproductive structure. Archegonium is the female structure which houses the eggs, while the antheridium is the male structure which contains all the sperms. The sperm travels from the antheridum to the archegonium with moisture and fertilizes. The newly formed zygote goes trhough mitosos until it is a sporophyte (2n). The sporophyte generation is dependent and attached to the gameotophyte. Then when it is fully developed the capsule on top release spores (hapliods n) into the envroment until it germinates in soil, where then develops into a gameotophyte.
Pteridophyta- Ferns- Sporophyte dominant, gameotphayte called prothallus and used only to produce gametes. The sporophyte is diploid (2n) and multicellular and when ready to reproduce goes trhough meisos to create haploid spores. The go through mitosis until they are a gameotophyte (n), which continures mitosis until they have gametes, which then fertilize to become a diploid (2n) zygote, which then again goes through mitosos until it’s a full sporophyte.
Gymnosperms- evergreens, confiers- Sporophyte dominant, gameotophyte used for gamete production. The sporophyte, which is the full fledged tree, produces male and female parts called a seed cone (female) and pollen cone (Male). Their sprocytesilize s to then go thorugh meiosis until they are gameotophytes. The two gendered gametphyte, male being a pollen grain (contains the sperm) and female being the eggs in the archegonium, then meet trhough wind pollination. It takes a large time period to fertilize ince the pollen grains must produce a pollen tube to reach the eggs. Once fertilized, the diploid zygote undergoes mitosis until it is a seed, which then continues to go under mitosis until it’s a tree. Then the cycle repeats.
Angiosperms- flowering plants- Sporophyte dominant, gameotphytes for gamete production. The sporophyre, which lives as many things in this cycle. It begins as a flower, which conatins all the reproductive organs, then meiosis is quick while the male gametes are pollinated into the pollen tubes where they travel down to the eggs. Then when fertilized, mitosis kicks in and may become a fruit, which conatins seeds to be dispributed by animals etc. Then the seed germinates and grows into the flower, where the cycle repeats.
4. Describe the organization of an angiosperm including the functions of each part you describe.
The angiosperm, or flowering plant, is composed of many structur In the basic body overview, you se the basics, roots, stem, leafs and flowers. In the flower you can see all the reproductive structures.
The leafs-used for attracting pollinators, and photosynthesis
The sepal- support and protection
Carpel-female structures
1. Stigma- the sticky top which catches pollen
2. Style- the long tube which the sperm travels down to reach the eggs
3. Ovary- The surrounding structure which encases the ovules/ eggs
4. Ovule- The casing which conatisn th female gamres (eggs)
Stamen- the male structures
1. Anther- the bussel of pollen which is picked uip or sperm for fertilization
2. Filament- the strural support which holds up and etend the anther
5. Your drawings of the slides from the Algae, Bryophytes and Pteridophytes microscope lab.