Unit 4 Lesson 3 Digital Lesson Companion Sexual & Asexual

advertisement
Unit 4 Lesson 3 Digital Lesson Companion
Sexual & Asexual Reproduction
Screen 2 - Earthworm reproduction
1. Do only animals reproduce sexually? Explain your reasoning.
Screen 3 - Sexual reproduction
2. True or False: All species are always limited to either sexual or asexual reproduction. Explain
your answer.
3. If an organism starts from only one cell, how do we get different body parts and organs?
4. Yes or No: If a characteristic of a parent, such as eye color, does not show up in offspring, is it
gone forever? Explain your answer.
Screen 4 - Asexual reproduction
5. What might be a disadvantage to an organism that multiplies rapidly through binary fission?
6. Which type of asexual reproduction results from mitosis?
a. Vegetative Propagation
b. Binary Fission
c. Budding
Screen 5 - Sexual versus asexual
7. What disadvantages of sexual reproduction can be seen in the way humans reproduce in
comparison to animals (think of how many babies animals have, how they care for their young,
etc.)?
8. What advantage might a hermaphrodite have in terms of reproduction?
Screen 6 - Sexual or asexual?
9. Is it an advantage or disadvantage for an organism to be able to reproduce both sexually and
asexually? Explain your answer.
10. In organisms that use sexual reproduction, what will eventually happen to traits that put an
organism at a disadvantage? Mark your answer choice below.
___Those traits will appear in more offspring since individuals that have those traits are more likely
to survive and pass it on to their offspring.
___Those traits will appear in fewer offspring since individuals that have those traits are less likely
to survive and pass it on to their offspring.
Screen 7 - Advantages of sexual reproduction
11. When a plant reproduces through asexual reproduction, a new plant results. Will that new
plant also be able to reproduce itself through asexual reproduction?
12. True or False: The offspring produced through sexual reproduction do not look identical to
their parent. Explain why or why not.
13. What characteristics did you get from your parents? Which parent did they come from?
14. Mark an X for any of the characteristics described below that help sexually reproducing
organisms increase their chances for reproduction?
____Some animals have bright coloring that helps them attract a mate.
____Flowering plants have bright petals that help them attract insects to pollinate them.
____Some animals use their sense of smell to find a mate.
____Some animals hibernate in the winter.
Screen 8 - Sperm and eggs
15. Do you think the first organisms on Earth used sexual or asexual reproduction? Why do you
think so?
16. What is similar between all types of asexual reproduction?
17. When an animal is cloned, is it the result of sexual or asexual reproduction?
Unit 4 Lesson 3 Digital Lesson Companion ANSWER KEY
Sexual & Asexual Reproduction
Screen 2 - Earthworm reproduction
1. Do only animals reproduce sexually? Explain your reasoning.
No, most multicellular organisms reproduce sexually.
Screen 3 - Sexual reproduction
2. True or False: All species are always limited to either sexual or asexual reproduction. Explain
your answer.
No, some organisms, such as algae and bacteria, can reproduce either sexually or asexually.
3. If an organism starts from only one cell, how do we get different body parts and organs?
During the process of cell division, as the cell multiply, they begin to differentiate, with different types of
cells developing into different organs and systems in the body.
4. Yes or No: If a characteristic of a parent, such as eye color, does not show up in offspring, is it
gone forever? Explain your answer.
No, some recessive traits may be carried by the offspring, but may not show up until a later generation.
Screen 4 - Asexual reproduction
5. What might be a disadvantage to an organism that multiplies rapidly through binary fission?
If it multiplies too rapidly, the population will get too big, and it will consume all available resources,
such as air, water, and food. When resources have been used up, the organisms may die.
6. Which type of asexual reproduction results from mitosis?
a. Vegetative Propagation
b. Binary Fission
c. Budding
Screen 5 - Sexual versus asexual
7. What disadvantages of sexual reproduction can be seen in the way humans reproduce in
comparison to animals (think of how many babies animals have, how they care for their young,
etc.)?
Humans usually only have one child at a time, and they take a long time to develop, compared to other
animals. Humans offspring also require much care to develop into adults.
8. What advantage might a hermaphrodite have in terms of reproduction?
The organism won't have to seek out and find an individual of the opposite sex. It can reproduce with
any other organism of its kind.
Screen 6 - Sexual or asexual?
9. Is it an advantage or disadvantage for an organism to be able to reproduce both sexually and
asexually? Explain your answer.
An individual may not be able to find a mate, so asexual reproduction allows them to reproduce
without a partner.
10. In organisms that use sexual reproduction, what will eventually happen to traits that put an
organism at a disadvantage? Mark your answer choice below.
___Those traits will appear in more offspring since individuals that have those traits are more likely
to survive and pass it on to their offspring.
_x__Those traits will appear in fewer offspring since individuals that have those traits are less likely
to survive and pass it on to their offspring.
Screen 7 - Advantages of sexual reproduction
11. When a plant reproduces through asexual reproduction, a new plant results. Will that new
plant also be able to reproduce itself through asexual reproduction?
Yes, just like the parent plant, that new plant does not need a partner to reproduce. This can contribute
to the rapid development of offspring since each offspring can individually have multiple offspring.
12. True or False: The offspring produced through sexual reproduction do not look identical to
their parent. Explain why or why not.
Offspring aren't identical to either parent because half of the chromosomes come from one parent and
half from the other parent.
13. What characteristics did you get from your parents? Which parent did they come from?
You inherited traits such as your eye color, hair color, or height. There are many other traits you may
have inherited. You may have inherited blond hair from your father and green eyes from your mother.
You might be tall, like your father, or have large earlobes, like your mother.
14. Mark an X for any of the characteristics described below that help sexually reproducing
organisms increase their chances for reproduction?
__X__Some animals have bright coloring that helps them attract a mate.
__X__Flowering plants have bright petals that help them attract insects to pollinate them.
__X__Some animals use their sense of smell to find a mate.
____Some animals hibernate in the winter.
Screen 8 - Sperm and eggs
15. Do you think the first organisms on Earth used sexual or asexual reproduction? Why do you
think so?
The first organisms on Earth used asexual reproduction. These organisms needed to survive in a
harsh environment, so asexual reproduction would provide a more efficient method of
reproduction under these conditions.
16. What is similar between all types of asexual reproduction?
The resulting offspring are all genetically identical to the parent organisms.
17. When an animal is cloned, is it the result of sexual or asexual reproduction?
Cloning is a type of asexual reproduction because it does not involve fertilization of a female
gamete by a male gamete. The offspring arise from only one parent.
Download