Chapter 6.2 CC

Question 1

How do purple sea urchins reproduce

Answer 1

-bring gametes together by releasing big clouds of sperm and egg cells into the water where it gets fertilized

Question 2

How come when the purple sea urchin gametes are in the air, the green sea urchin gametes don’t get fertilized?

Answer 2

-sperm and egg cells of all species of sea urchins have unique protein on their surfaces, only works if right protein meets right sugar

Question 3

What is sugar-protein recognition

Answer 3

-fertilization in a particular species of sea urchins will only occur if right sugar meets right protein

Question 4

What is mating

Answer 4

-process that gametes arrive at same time and place

Question 5

What are the two ways of sexually reproducing?

Answer 5

• internal fertilization

- external fertilization

Question 6

What conditions must be made in order for cell division after fertilization?

Answer 6

• enough nutrients for rapidly diving embryo
• warm temperature so proteins and enzymes function properly during chemical reactions in embryo
• enough moisture so embryo doesn’t dry up
• embryo must be protected by predators and other environmental factors

Question 7

What happens in external fertilization?

Answer 7

• Sperm and egg cell meet outside bodies of parents

- come in contact with egg cell of same species, fertilization

Question 8

Name 2 examples that use external fertilization?

Answer 8

• sea urchins
• salmon
• mosses and ferns, carried by water

Question 9

What is spawning?

Answer 9

-what make and female of both species release gametes into water

Question 10

How many eggs do a female sea urchin produce?

Answer 10

Several millions per year,

80% mass during mating season

Question 11

Describe internal fertilization?

Answer 11

-sperm cells deposited in females body where they meet the egg cell

-single sperm cell penetrated into egg cell
egg cell changes electrical charge, not allowing more sperm to come in

• embryo develops, nourished in body for long time, embryo protected from predators

Question 12

What is preventing the entrance of more then one sperm cell going into egg cells important?

Answer 12

-to make sure only one set of make chromosome can unite with chromosomes in the nucleus of cell

Question 13

What is sexual reproduction

Answer 13

-reproduction that requires two parents and produces offspring genetically different from each other, either parent or any other member of species

Question 14

What are the 3 stages of sexual reproduction?

Answer 14

-Mating, fertilization, development

Question 15

What are the advantages of sexual reproduction?

Answer 15

-offspring genetically different from parents

Question 16

What is the difference of sexual reproduction?

Answer 16

-parent care difference

Question 17

What are the 2 advantages of external fertilization?

Answer 17

• little energy to find mate

- greater number of offspring can repopulate area after disaster

Question 18

What is the disadvantage of external fertilization?

Answer 18

-gametes, embryos and offspring unprotected and often preyed upon

Question 19

What is the advantage of internal fertilization?

Answer 19

-more protection from embryo

more parental care for offspring

Question 20

What are the 2 disadvantages of internal fertilization?

Answer 20

• fewer offspring produced so if number of predators increase, population decrease
• more energy needed to find mate