what are the different charateristics of animal, plant and fungi sexual life cycles?

Question

i really need to know for Ap biology. i am so stuck on this question. thanks for ur help!

Answer 1

Hi Erica,

I'd waste both your and my time if I try to answer this question with lots of detail. I'd suggest you go to your textbook, flip a few pages here and there, get a broad idea and then, come back and read this answer.

Please notice that I'll have to make this answer less complex by generalizing concepts and avoiding some fine details which you can easily read in your textbook.

Now, without wasting much time, here is my answer-

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Characteristics of animal sexual life cycles-

1- Usually, there are two parents- male and female. Both form special haploid cells called gametes by meiosis.

2- Gametes fuse in pairs to form diploid cells called zygotes (fertilization).

3- Repeated mitotic divisions of the zygote forms embryos.

4- And the embryo develops into a new individual.

Sooo simple!

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Characteristics of plant sexual life cycles-

It is same as animal sexual reproduction. Just that the technical terms and the methods of reproduction are a little different in flowering and non-flowering plants. I suggest you to read your textbook for the detailed terminology.

In plants-

1- Diploid sporophytic cells divide by meiosis to give haploid gametophytic cells.

2- Haploid gametophytic cells from male and female fuse to form the diploid zygote.

3- The zygote then develops into an embryo and then to a full diploid plant body.

* There are lots of finer details like the flowering system in flowering plants: pollens, ovules etc. and sporangia in non-flowering plants. I suggest you to study the life cycles of different bryophytes, gymnospermae and angiospermae to get the idea.

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Characteristics of fungal sexual life cycles-

1- It involves fusion of two compatible sex cells/ gametes. The sex organs that produce gametes are called gametangia.

2- The gametangia of fungi are unicellular and are surrounded by a sterile jacket. In fungi, there is a gradual reduction in sexuality from lower to the higher fungi.

3- In the first stage, the cytoplasms of two sex cells fuse with each other but the nuclei do not fuse. The cell is thus called a dikaryon. (Plasmogamy).

4- The nuclei then fuse to form the synkaryon. (Karyogamy).

5- The diploid cell after that, produces haploid nuclei by meiosis.

There are broadly five types of sexual fusion in fungi.

Here they are-
1- Planogametic copulation.
One or both of the gametes are motile.

2- Gametangial contact.
The two gametangia come together and the male gametangia forms a tube through which the male non-motile gamete is sent to the female gametangia.

3- Gametangial copulation.
The gametangia themselves fuse together and lose their sexual identities to form zygospore.

4- Spermatization.
Numerous spore-like minute bodies (spermatia) are sent through various agencies to the receptive hyphae or trychogyne of female gametangium.

5- Somatogamy.
In this mode, sex organs are not formed and the fusion occurs two vegetative cells resulting in the formation of dikaryon.

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I hope the above info helps.

Answer 2

Animal Sexual