Flashcards in Chapter 6.2 CC Deck (20):
How do purple sea urchins reproduce
-bring gametes together by releasing big clouds of sperm and egg cells into the water where it gets fertilized
How come when the purple sea urchin gametes are in the air, the green sea urchin gametes don't get fertilized?
-sperm and egg cells of all species of sea urchins have unique protein on their surfaces, only works if right protein meets right sugar
What is sugar-protein recognition
-fertilization in a particular species of sea urchins will only occur if right sugar meets right protein
What is mating
-process that gametes arrive at same time and place
What are the two ways of sexually reproducing?
What conditions must be made in order for cell division after fertilization?
-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
What happens in external fertilization?
-Sperm and egg cell meet outside bodies of parents
-come in contact with egg cell of same species, fertilization
Name 2 examples that use external fertilization?
-mosses and ferns, carried by water
What is spawning?
-what make and female of both species release gametes into water
How many eggs do a female sea urchin produce?
Several millions per year,
80% mass during mating season
Describe internal fertilization?
-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
What is preventing the entrance of more then one sperm cell going into egg cells important?
-to make sure only one set of make chromosome can unite with chromosomes in the nucleus of cell
What is sexual reproduction
-reproduction that requires two parents and produces offspring genetically different from each other, either parent or any other member of species
What are the 3 stages of sexual reproduction?
-Mating, fertilization, development
What are the advantages of sexual reproduction?
-offspring genetically different from parents
What is the difference of sexual reproduction?
-parent care difference
What are the 2 advantages of external fertilization?
-little energy to find mate
-greater number of offspring can repopulate area after disaster
What is the disadvantage of external fertilization?
-gametes, embryos and offspring unprotected and often preyed upon
What is the advantage of internal fertilization?
-more protection from embryo
more parental care for offspring