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The most obvious importance of help determine many of the
angiosperms for animals, including characteristics of the offspring.
humans, is as a source of food.
Corn, potatoes, peanuts, and
beans all come from angiosperms.
All fruit is from angiosperms.
Besides food, angiosperms are the
source of other important products.
Cotton for cloth and hardwood
trees for lumber also come from
this very common group. No other
group of plants is more important
for people and other animals. Figure 9 – Chromosomes determine many
of the characteristics of living things.
Plant Reproduction
Plants have two types of
Think about animal reproduction generations. The first generation
for a moment. A parent has an is gametophyte generation.
offspring who looks pretty similar Gametophytes are haploid. This
to them. Sure, they may be means that the plant has only one
smaller when they are first born, set of chromosomes. The
but animal offspring are pretty gametophyte produces the cells
much the same as their parents. needed for reproduction, called
This is not true in plants. In fact, gametes, sperm and egg, through
plants undergo a process known as a process known as mitosis. In
alternation of generations, in which mitosis a cell splits into two cells,
the offspring are dramatically each of which has the same
different than the parents. number of chromosomes as the
original cell. So, since
In order to understand plant gametophytes are haploid,
reproduction, it is important to gametes are haploid too.
understand chromosomes.
Chromosomes are the places in the Next, the sperm fertilizes the egg,
cells where genetic information, or producing an offspring. This
DNA, is found. When a new offspring is referred to as the
organism is formed, information sporophyte generation. Since the
from the chromosomes of the sporophyte is created from the
parents or parents is passed on to combination of two haploid cells, it
the offspring. These chromosomes has two sets of chromosomes.
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