1. In plants, sexual reproduction occurs when sperm and egg unite to form a...

a. gamete
b. gametophyte
c. sporophyte
d. zygote

Is it d?

2. A plant continues to grow throughout its life through the use of s a process called...

a. alternation of generations
b. photosynthesis
c. dormancy
d. germination

Is it b?

3. Which is one advantage of sexual reproduction?

a. More offspring are produced.
b. More offspring survive to maturity
c. The offspring have more genetic variation.
d. The offspring and the parents are identical.

Is it c?

4. Which is one advantage of external fertilization?

a. The offspring are genetically identical to the parents.
b. More eggs can be fertilized at one time.
c. More sperm can be released at one time.
d. More protection is available for developing zygotes.

Could it be either b or c? Or none...

Thanks anyone who comments on this! You're the best!

Hello? It's me.

Hel-lo?

Wait, hold on. 4 is b.

Since Jiskha doesn't have a biology expert at this time, please try posting your question at this site.

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Choose from the general topics at the right and then find the specifics you need within each topic.

1. You are correct, the answer is d. Plants reproduce sexually when the sperm and egg unite to form a zygote. To arrive at this answer, you can break down the options:

a. Gametes are the specialized reproductive cells (sperm and egg) that unite during sexual reproduction, so it is not the correct answer.
b. Gametophyte refers to the multicellular haploid phase in the life cycle of plants, where gametes are produced. The fusion of these gametes results in the formation of a zygote, not a gametophyte.
c. Sporophyte is the multicellular diploid phase in the plant life cycle, which produces haploid spores. It does not directly form a zygote.
d. A zygote is the diploid cell resulting from the fusion of sperm and egg during sexual reproduction. This is the correct answer.

2. The correct answer for this question is a. A plant continues to grow throughout its life through the process called alternation of generations. To determine this, let's break down the options:

a. Alternation of generations refers to the alternation between two multicellular phases in the plant life cycle, the haploid gametophyte and the diploid sporophyte. This cycle allows continuous growth and reproduction.
b. Photosynthesis is the process by which plants convert light energy into chemical energy, enabling them to produce their food. While photosynthesis is essential for plant growth, it is not the correct answer in this context.
c. Dormancy is a state of reduced activity and growth that some plants enter during unfavorable conditions. It is not the process that allows continuous growth.
d. Germination is the process by which a seed begins to grow into a new plant. While it represents the beginning of growth, it does not explain how a plant continues to grow throughout its entire life.

3. You are correct once again. The answer is c. One advantage of sexual reproduction is that the offspring have more genetic variation. To understand why, let's consider the options:

a. While sexual reproduction can result in more offspring being produced compared to asexual reproduction, this is not necessarily an advantage in itself. The quality of offspring is more important than the quantity.
b. Asexual reproduction can sometimes result in more offspring surviving to maturity because they are genetically identical to the parent, which means they inherit the parent's traits that help them thrive. However, this is not the case with sexual reproduction.
c. The main advantage of sexual reproduction is the generation of genetically diverse offspring. This genetic variation allows for adaptation to changing environments, increases the chances of survival, and leads to evolutionary innovation.
d. Offspring and parents being identical is not an advantage of sexual reproduction. In fact, it is a characteristic of asexual reproduction.

4. The correct answer is b. One advantage of external fertilization is that more eggs can be fertilized at one time. Let's analyze the options to understand why:

a. The offspring being genetically identical to the parents is not an advantage of external fertilization. In fact, external fertilization often leads to greater genetic diversity due to the potential for many different sperm to fertilize many different eggs.
b. External fertilization, which occurs outside the body of the parent organisms, allows for the simultaneous release of many eggs and sperm into the environment. The large number of eggs and sperm increases the chances of successful fertilization.
c. Similar to option b, external fertilization allows for the release of a large number of sperm at one time, increasing the chances of successful fertilization.
d. More protection being available for developing zygotes is not generally associated with external fertilization. In many cases, external fertilization provides limited or no protection for developing offspring, as they are exposed to potentially harsh environmental conditions.

I hope this explanation helps! Let me know if you have any further questions.