Chapter 6.2

Question 1

How does nature ensure sexual reproduction to occur within the same species?

Answer 1

Sperm and egg cells have unique proteins and sugars on their surface.
The fertilization of an egg will occur only if the right sugar meets the right protein of the same species.

Question 2

What are the 3 stages of reproduction?

Answer 2

mating, fertilization, development

Question 3

What is the difference between external fertilization and internal fertilization?

Answer 3

External: Sperm and egg cell unites outside the bodies of the parents

Internal: Sperm is deposited inside the female’s body where it meets the egg cell

Question 4

What type of organisms use external fertilization?

Answer 4

Aquatic animals and plants.

ex: sea urchins, fish, mosses

Question 5

What are the advantages of external fertilization?

Answer 5

Little energy is required to find a mate, large numbers of offspring can be produced at one time

Question 6

What are the disadvantages of external fertilization?

Answer 6

Zygotes are unprotected and often preyed upon. Parents do not care for offspring so few survive adulthood

Question 7

What type of organisms use internal fertilization?

Answer 7

mostly land animals and plants

ex: humans, snakes, flowering plants

Question 8

What are the advantages of internal fertilization?

Answer 8

More offspring survive because of embryo protection and parental care

Question 9

What are the disadvantages of internal fertilization?

Answer 9

Requires more energy to find a mate and results in fewer zygotes produced

Question 10

What type of fertilization is pollination

Answer 10

Internal

Question 11

What happens during pollination?

Answer 11

Male gametes are transferred from the male reproductive system (stomen) to the female reproductive part of the plant (pistil)

Pollen grains carry the sperm cells in a protective case to the ovaries

Question 12

What are other methods of pollination?

Answer 12

Some plants that do not attract pollinators release their pollen into the air.

Seeds or cones are carried by the wind or birds.

Question 13

What are the advantages of sexual reproduction? (4)

Answer 13

1. Very little energy required to find a mate (external)
2. Greater numbers of offspring can repopulate an area after a disaster (external)
3. More protection is given to the embryo and more parental care is given to offspring (internal)
4. Offspring are genetically different from their parents so the may survive new diseases or other threats that appear in a population*

Question 14

What are the disadvantages of sexual reproduction? (3)

Answer 14

1. More energy required to find a mate (internal)
2. Fewer offspring produced so if the number of predators increases, a population will decline (internal)
3. Gametes, embryos and offspring are unprotected and are often preyed upon (external)