Module 3:2 Lesson

Module 3: Lesson 2
Types of Reproduction

Organisms reproduce and transfer their genetic information to their offspring, BUT HOW?

​Do they produce eggs?

​Five friends looked at a chicken egg. They wondered if other organisms besides chickens, produce eggs from Reproduction. They each had a different idea.

Poll

Eddie: I think only birds produce eggs.

Vernon: I think only amphibians, reptiles, and birds produce eggs

Forest: I think all animals, except mammals, produce eggs

Angie: I think all animals, except humans, produce eggs

Sophie: I think all animals, including humans, produce eggs

• Eddie

• Vernon

• Forest

• Angie

• Sophie

​How does this sea star reproduce?

​Sea stars may be interesting to watch, but they can also be pests to fishermen. At one time, fishermen noticed that sea stars were eating all the clams and other mollusks they were trying to catch. The fishermen tried to get rid of the sea stars by chopping them up and throwing them back into the ocean. When the fishermen returned to the area weeks later, they noticed that the number of sea stars had grown much larger. How is this possible? Make a diagram illustrating how you think the sea star population grew in size?

Open Ended

Why do you think more sea stars appeared?

How can one organism make more organisms?

​You learned about many sea stars appearing when they were thought to have been removed from the environment. How is it possible that the sea stars increased their numbers after they have been chopped up?

​Plant Progeny

Observe two plants- a seed potato and a coleus stem- in glasses of water. Look at photos on the plants when they were first place in water. Draw a detailed diagram of each of the glasses in your Science Notebook. Observe the plants a week after placement in the water and write down your observations in your Science Notebook.

​Investigation

​Asexual Reproduction

​Recall in the beginning of the lesson you read about sea stars reproducing after being cut up. This happened through regeneration. Regeneration occurs when an offspring grows from a piece of its parent. Just like sea stars, some plants don't need seeds to make new plants. Some plants can be grown from a leaf, a stem, or another plant part through vegetation reproduction. Vegetative reproduction is a form of asexual reproduction occurs when only one parent organism or part of that organism produces a new organism. The new organism is genetically identical to the parent.

Multiple Choice

What is the main characteristic of vegetative reproduction?

• It requires two parent organisms.

• The new organism is genetically different from the parent.

• It only occurs in animals.

• The new organism is genetically identical to the parent.

Multiple Choice

How does regeneration in sea stars compare to vegetative reproduction in plants?

• Both require seeds to grow new organisms.

• Both involve a single parent producing a genetically identical organism.

• Regeneration requires two parents, while vegetative reproduction requires only one.

• Vegetative reproduction occurs in animals, while regeneration occurs in plants.

​How do other organisms reproduce asexually?

​You just discovered asexual Reproduction in plants. Different types of plants, animals, and other organisms can reproduce asexually. However, not all asexually reproducing organisms follow the same type of reproduction. Take a look at the hydra below to see how it reproduces.

Open Ended

Examine the pictures of the hydra on page 33. What evidence do you observe that the hydra reproduced?

Open Ended

What are some advantages and disadvantages of this type of reproduction?

​Collect Evidence

​ How can one organism such as the sea star produce offspring that are identical to itself? Record your evidence (A) in the chart at the beginning of the lesson (pg 30).

​The hydra seen in the previous photos is budding. Budding is a form of asexual reproduction where an organism grows on the body of its parent.

Multiple Choice

Which of the following best describes the process of regeneration?

• The process where offspring are produced from seeds.

• The ability to grow a new organism from a part of the parent organism.

• The process where offspring inherit traits from both parents.

• The process of fertilization in plants.

Multiple Choice

Which of the following is an example of vegetative reproduction in plants?

• A seed growing into a plant.

• A new plant growing from a leaf, stem, or part of the parent plant.

• A flower producing pollen.

• A plant absorbing nutrients from the soil.

Multiple Choice

What is a key characteristic of asexual reproduction?

• It requires two parent organisms.

• It produces offspring that are genetically identical to the parent.

• It always involves seeds.

• It only occurs in animals.

Multiple Choice

How does budding in organisms like yeast or hydra differ from regeneration in sea stars in terms of how the offspring are produced?

• Budding produces new organisms that may remain attached before detaching, while regeneration grows a fully new organism from a detached part.

• Budding requires two parents, while regeneration occurs with just one parent organism.

• Budding produces offspring genetically different from the parent, while regeneration results in genetically identical offspring.

• Regeneration involves the entire parent organism growing a new offspring, while budding produces offspring by dividing the parent in half.

​Why do organisms have two parents?

​When an organism reproduces asexually, its offspring are genetically identical to the parent. Why aren't all organisms identical?


Complete the lab on page 34 with your face partner to search for this answer

​You just modeled the genetic result of organisms reproducing by using two parents through sexual reproduction. Sexual reproduction is a type of reproduction in which the genetic materials from two different cells combine, producing offspring that are genetically different from their parents. In sexual reproduction, each parent contributes half of the genes acquired by the offspring. Offspring have two of each chromosome and therefore two alleles of each gene, one acquired from each parent.

​Collect Evidence

​How can two organisms produce offspring that are not identical to themselves, unlike the sea star at the beginning of the lesson? Record you evidence (B) in the chart at the beginning of the lesson.

​Asexual VS Sexual Reproduction

Open Ended

A fatal disease is spreading through an aquarium containing both fish, which reproduce sexually, and sponges, which reproduce asexually. The disease has been identified in both species. Which species do you think will be most likely to survive?

​Collect Evidence

​What are the advantages and disadvantages of the different types of reproduction, such as that of the sea star at the beginning of the lesson? Record your evidence (C) in the chart at the beginning of the lesson (pg 31)

​Compare & Contrast

Multiple Choice

A tree produces seeds in pods when wind-borne pollen from another tree of the same species reaches the flowers. Each seed contains genetic information so the seed can grow into an adult tree. Which do you predict would be the effect of this process?

• The tree produces a large number of genetically diverse offspring.

• The tree produces a large number of genetically identical offspring.

• The tree produces a small number of offspring that are identical to the female parent.

• The tree produces a small number of offspring that are identical to the male parent.

Multiple Choice

Hydras are organisms that live in freshwater environments. They have a tube-like body and a mouth at one end. Around the mouth are stinging tentacles that help to capture food. Depending on the conditions, hydras can reproduce sexually or asexually. Based on your observation, which statement best explains what is happening to the hydra in the figure to the left

• 
  

  The hydra is reproducing asexually by budding a new hydra.

• The hydra is reproducing asexually by splitting in two.

• 
  

  The hydra is reproducing sexually by grafting to another hydra.

• The hydra is reproducing sexually by releasing sex cells into the water.