Title: Heredity and Reproduction
1Heredity and Reproduction
2Distinguish between sexual and asexual methods of
reproduction.
- Asexual reproduction reproduction in which a
single parent produces offspring that are
genetically identical to the parent - Sexual reproduction reproduction in which two
parents produces offspring that share
characteristics of both parents
3Recognize advantages and disadvantages of sexual
and asexual reproduction.
Variation usually helps a species survive when
the environment changes. Asexual reproduction
only requires one parent to produce a new plant.
It can therefore produce many plants very
quickly. This is an advantage in places where the
environment doesn't change very much (bacteria).
By building a large population of organisms very
quickly the species is able to thrive. The great
disadvantage is that when the environment
changes, all of the organisms will die, if they
do not have the ability to adapt to the
change. Sexual reproduction has the advantage of
providing lots of variation within a species,
helping it to survive when the environment
changes. The main disadvantage is that this
process takes a lot of energy. This means that
they can only produce small populations.
4Advantages Disadvantages of Asexual and Sexual
Reproduction
5Flowering Plants
- Flowering plants are the most abundant plants in
the world. They come in a wide variety of shapes
and sizes. The following are all examples of
different flowering plants - Oak trees
- Prickly-pear cactuses
- Irises
- Bermuda grass
- Bean stalks
6- Flowering plants can reproduce sexually. During
sexual reproduction, a sperm fertilizes an egg.
Both the egg and sperm cells are located within
the flower. - The process of plant fertilization is shown in
the illustration below
7Lets draw a flower and match the part with its
reproductive function.
Put the definition of each at the bottom of your
drawing.
8Definitions
- Anther where pollen is produced
- Egg female reproductive cell
- Ovary part that produces eggs
- Ovule - contains egg within the ovary of the
flower - Petal brightly colored part of the flower
- Pistil center of plant, develops in to fruit
when fertilized - Pollen male reproductive bodies
- Pollen tube tube that takes the pollen to the
egg - Sepal surrounds fertile organ of the flower
- Sperm cells male reproductive cells
- Stigma part that receives the pollen
9- Now put your definitions into a circle map!
10Pollination
- Pollination, the process of pollen grains moving
from the anthers to the stigmas, is the beginning
of the process of fertilization. -
- After the pollen lands on the stigmas, a tube
grows from the stigma to the ovary. The sperm
cells in the pollen travel down the tube and fuse
with eggs sitting in the ovule. - Fertilized eggs develop into seeds. The ovule
around the seeds develops into fruit.
11The following illustration shows how
fertilization leads to the development of fruit
and seeds
12- When a developed seed for a flowering plant is
dropped or planted in a suitable environment, the
seed begins to germinate, or sprout. Look at the
illustration below to see the stages a
germinating plant goes through
13- A few flowering plants are also able to
reproduce asexually. - That means the plant does not have to form
flowers, seeds, and fruits to produce a new
plant. - When a flowering plant reproduces asexually, a
part of the plant, such as a stem or root,
produces a new plant. The "eyes" you see growing
out of some potatoes are examples of asexual
reproduction.
14Recognize a variety of pollination methods and
associated floral adaptations.
- Pollination is the process by which pollen
grains are transferred from the male part of a
plant to the female part of a plant. - Floral adaptations are things that make the
flower more attractive to insects to aid in
pollination.
15Recognize a variety of pollination methods
- Insects - When an insect lands on a flower
(often to feed upon nectar), it may become coated
in the flower's pollen. When the insect lands on
another flower, the pollen grains it carried may
be deposited on the plant's female structure,
resulting in pollination.Animals - Animals can
aid in pollination in a way that is similar to
insects. When an animal feeds upon or comes in
contact with a flower, it can collect pollen
grains. When the animal contacts another flower,
the pollen grains may be deposited on the female
structure, resulting in pollination.Wind - Some
flowers depend upon wind to aid in pollination.
In wind-pollinating species, the pollen grains
are small and light so that they may be carried
through the air. Some of these pollen grains may
be deposited on the female structure of another
flower, resulting in pollination. An example of a
wind-pollinating flower is ragweed.Water -
Although rare, some flowers use water to aid in
pollination. In this process, pollen grains fall
into flowing water, such as a river or stream.
Later, the pollen grains may contact the female
structure of other plants, either at the surface
of the water or beneath the surface.
16Recognize a variety of pollination methods
- Insects lands on flower, picks up pollen,
deposits it onto another flower. - Animals comes in contact with a flower, picks
up pollen, then comes in contact with another
flower and deposits onto the flower. - Wind blows pollen from one flower through the
air to another flower. - Water (rare) pollen falls into flowing water
and comes in contact with another flower.
17Floral Adaptations
- Over time, plants have developed a variety of
adaptations that aid in pollination. -
- For example, plants that are pollinated by
insects and other animals have developed
brightly-colored flowers and sweet-smelling
nectar. These traits attract potential
pollinators. -
- Wind-pollinating plants have developed light,
feathery pollen grains that are easily
transported by the wind.
18- Lets put that into a
- Tree Map!
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20 21- STUDY GUIDE!!!!!!!!!
- Be able to label the flower with the parts needed
for reproduction. (all 12 listed in notes) - Be able to match a flower part with its
reproductive function. (all 11 definitions listed
in notes) - Be able to distinguish between sexual and asexual
methods of reproduction. - Be able to recognize advantages and disadvantages
of sexual and asexual reproduction. - Be able to recognize a variety of pollination
methods and associated floral adaptations.