Chapter 3: Reproduction of Organisms
Lesson 3.1- Sexual Reproduction and Meiosis
1.
2.
combines genetic material from two different parent cells.
Sexual reproduction creates genetic variation, which helps populations survive changing
___________________ conditions and
3.
.
The major disadvantages of sexual reproduction are the need to get
and _________together,
and the time needed for organisms to reach an age when they can
A.
.
Importance of Meiosis
1.
2.
is cell division that produces sperm or egg cells in sexually reproducing organisms.
Meiosis ensures that species’ offspring inherit the correct number of
______________.
3.
Meiosis produces
sperm and egg cells, which combine to form a diploid
.
4.
A
organism is produced when sex cells combine. The fusing of a haploid sperm cell
and a haploid egg cell is called
a diploid
a. A
. The new cell formed from fertilization is called
___________.
is a fertilized egg.
b. A cell that contains a pair of homologous chromosomes is a
c.
B.
.
are half the set of the reproductive cell, or parent cell.
Phases of Meiosis
1.
Meiosis I
a. Prophase I: Nuclear membranes break apart and pairs of ____________
chromosomes line up
close to each other.
b.
I: Pairs of chromosomes line up along the middle of the cell, and fibers
attach to each pair of sister chromatids.
c. Anaphase I: Sister chromatids move to
ends of the cell.
d. Telophase I: Nuclear membranes form and
divides, producing two cells. Two
divisions of the nucleus occur in meiosis.
2.
Meiosis II
a. Prophase II: Chromosomes do not
b. Metaphase II:
c.
d.
C.
Meiosis results in
before nuclear membrane breaks apart.
line up along the center of the cell.
: Sister chromatids separate, moving to opposite ends of the cell.
II: Nuclear membranes reform and the cytoplasm divides.
cells produced from
cell.
1.
Meiosis I produces two
2.
Meiosis II produces two
different cells.
haploid cells from each cell produced in
meiosis I.
Lesson 3.2- Plant Reproduction
A.
Organisms, such as plants that alternate between diploid and haploid stages have alternations of
.
1.
In seedless plants, the
2.
In seed plants, the haploid generation lives within
B.
generation lives on its own.
tissue.
Reproduction of Seedless Plants
1.
Seedless plants, such as moss and ferns, grow from haploid
2.
are daughter cells produced from haploid structures. Spores grow by mitosis and cell
division to form
3.
, not seeds.
plants.
Fertilization results in a diploid zygote that grows by mitosis and cell division into the tiny
generation.
C.
Reproduction of Seed Plants
1.
Sperm cells form inside a hard, protective structure called a
2.
Egg cells form inside a female reproductive structure called an
3.
In
4.
When sperm enters the ovule,
5.
A
consists of an embryo, food supply, and protective covering.
6.
An
is an immature diploid plant.
D.
.
.
, pollen grains from the male structure reach the female structure.
occurs, and a seed develops.
Flowerless Seed Plants (Gymnosperms)
1.
Male cones produce
2.
3.
E.
and female cones produce
.
form as part of the female cone.
Examples are pines, firs, cypresses, redwoods, and yews.
Flowering Seed Plants (Angiosperms)
1.
The flower’s male reproductive organ is the
2.
The
3.
The
4.
The
5.
The pollen grains land on the pistil’s
6.
A
grows from the pollen grain into the stigma, down the style, to the ovary,
where
occurs.
7.
; the female organ is the
consists of an anther and a filament.
forms the pollen grains at the stamen’s tip.
is a long stalk that connects the anther to the base of the flower.
Each ovule and its embryo will become a
, which is at the top of a long tube called the style.
.
.
8.
The
of the plant protects the seed and helps with seed dispersal.
Lesson 3.3-Animal Reproduction
A. Animal Reproductive Organs
1. Separate male and female organisms have reproductive organs called
2. Male gonads called
.
produce sperm cells; female gonads called
____________
produce egg cells.
3. An egg is usually fertilized in the
.
B. Fertilization
1.
fertilization takes place inside the body of an organism.
a.
deposit sperm in or near the female’s reproductive system.
b. Animals that use internal fertilization usually protect their eggs during
_________________.
c. Examples: earthworms, spiders, insects, reptiles (turtle), birds, mammals.
fertilization takes place outside the organism’s body.
2.
a. The female usually releases
into water when the male releases sperm into the water.
b. Most animals that use external fertilization do not
their eggs or care for their young.
c. Large number of eggs are produced to ensure that some offspring will survive.
d. Examples: jellyfishes, clams, sea urchins, sea stars, and many species of fish.
C. Embryo Development (zygote to embryo)
1. Embryo development in most animals occurs
the mother, in an egg surrounded by a protective
covering.
a. Eggs laid by a lizard, snake, and other reptile have a tough, leathery covering. A tough, jellylike
substance usually surrounds eggs laid under water. Bird eggs have a hard
covering called a shell. Most eggs contain a
yolk that provides a food supply for the developing young.
2. In
, an animal (amphibians and many animals without backbones) goes through several
stages of development.
a. Metamorphosis is a developmental process in which the form of the body changes as an animal
grows from the egg to an adult.
a. ex: Butterfly- larvae, caterpillar, cocoon, butterfly
b. ex: Frog- egg, early tadpole, late tadpole, adult frog
3. Embryos that develop
the mother get nourishment in two different ways.
a. Some develop inside an egg with a yolk within the mother’s body, until they _____________ and
leave the mother’s body. (examples: snakes, reptiles, insects, some fish)
b. Others, including most
, get nourishment directly from the mother. (examples: whales,
sharks, pigs, kangaroos)
4.
is the length of time between the fertilization and birth of an animal.
5. The correct sequence for sexual reproduction is fertilization, zygote,
, to live offspring.
Lesson 3.4- Asexual Reproduction
A.
What is asexual reproduction?
1.
reproduction produces offspring from a single parent that is
to the parent organism.
2.
Asexual reproduction takes
time and energy than sexual reproduction because they
don’t have to find a mate and produce the offspring, and organisms well-
to the
environment always produce well-adapted offspring.
3.
Lack of genetic
makes populations more susceptible to disease, changes in
the environment, and harmful
B.
.
Types of Asexual Reproduction
1.
Bacteria, prokaryotes, which have no nucleus, reproduce by
, or producing two
identical cells. Example: E. coli
2.
Some single-celled eukaryotes, reproduce by
3.
Yeast, single-celled eukaryotes, reproduces by
, followed by cell division.
, in which a new organism
grows from the body of the parent organism.
4.
Many plants can reproduce from
, in addition to reproducing sexually.
is a type of reproduction where you can grow a new plant from a stem of the original plant.
produces a new organism from part of an animal’s body.
5.
Regeneration can also mean regrowth of a missing animal part.
Example: planarian
C. Cloning
1. Scientists can
plants to produce identical plants with desirable genetic traits.
2. Animals can be cloned in the lab, but they are often not as
.