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The seed forms in an ovary, which enlarges as the seeds grow. As the seed develops, the walls of the ovary also thicken and form the fruit. In botany, a fruit is a fertilized and fully grown, ripened ovary. Many foods commonly called vegetables are actually fruit. Eggplants, zucchini, string beans, and bell peppers are all technically fruit because they contain seeds and are derived from the thick ovary tissue. Acorns and winged maple keys, whose scientific name is a samara, are also fruit.

Mature fruit can be described as fleshy or dry. Fleshy fruit include the familiar berries, peaches, apples, grapes, and tomatoes. Rice, wheat, and nuts are examples of dry fruit. Another distinction is that not all fruits are derived from the ovary. Some fruits are derived from separate ovaries in a single flower, such as the raspberry. Other fruits, such as the pineapple, form from clusters of flowers. Additionally, some fruits, like watermelon and orange, have rinds. Regardless of how they are formed, fruits are an agent of dispersal. The variety of shapes and characteristics reflect the mode of dispersal. The light, dry fruits of trees and dandelions are carried by the wind. Floating coconuts are transported by water. Some fruits are colored, perfumed, sweet, and nutritious to attract herbivores, which eat the fruit and disperse the tough undigested seeds in their feces. Other fruits have burs and hooks that cling to fur and hitch rides on animals.

The life cycle of an angiosperm

The adult, or sporophyte, phase is the main phase in an angiosperm’s life cycle. Like gymnosperms, angiosperms are heterosporous. They produce microspores, which develop into pollen grains (the male gametophytes), and megaspores, which form an ovule containing the female gametophytes. Inside the anthers’ microsporangia ( [link] ), male microsporocytes divide by meiosis, generating haploid microspores that undergo mitosis and give rise to pollen grains. Each pollen grain contains two cells: one generative cell that will divide into two sperm, and a second cell that will become the pollen tube cell.

Art connection

Illustration shows a tulip in cross section at the top of a clockwise circular series of images. An enlargement of the anther shows microsporangium inside. One microspore (the “mother cell”) undergoes meiosis to the four-cell stage. The mother cell then undergoes mitosis to become a microgametophyte, or pollen grain. Counterclockwise from the flower cross section, an ovary is shown with several macrospore ovules inside. One is shown developing into the embryo sac through meiosis then mitosis. At the bottom of the illustration, the pollen grain lands on the stigma of a flower, and a pollen tube grows from the pollen grain down inside the style to the ovary. The pollen tube contains a pollen tube nucleus and two sperm. The sperm fertilize the egg and the polar nuclei within the embryo sac (double fertilization).
This diagram shows the lifecycle of an angiosperm. Anthers and ovaries are structures that shelter the actual gametophytes: the pollen grain and embryo sac. Double fertilization is a process unique to angiosperms. (credit: modification of work by Mariana Ruiz Villareal)

If a flower lacked a megasporangium, what type of gamete would it not be able to form? If it lacked a microsporangium, what type of gamete would not form?

In the ovules, the female gametophyte is produced when a megasporocyte undergoes meiosis to produce four haploid megaspores. One of these is larger than the others and undergoes mitosis to form the female gametophyte or embryo sac. Three mitotic divisions produce eight nuclei in seven cells. The egg and two cells move to one end of the embryo sac (gametophyte) and three cells move to the other end. Two of the nuclei remain in a single cell and fuse to form a 2 n nucleus; this cell moves to the center of the embryo sac.

Questions & Answers

it is the situation where by im a market there is only one supplier and producer of a certain comodity that has no close substitute or competitor
Sepiso Reply
what is demand and supply
what is Economics?
Pintu Reply
Is the study of human behaviour as a relationship between ends and scares mean which have alternative use
what is monopoly
what are the difficultés if retail prix index for calculating thé value of money
hmm OK wait
what is labour
Mamudou Reply
LABOUR is a measure of work done by human being
It is all form of human effort use to utilize in production
Why is scarcity a foundermental problem in economics
Why is scarcity a foundermental problem in economics
Alhaji Reply
scarcity occur unbalance demand and supply at this time cost goods increase then inflation very increase
scarcity is a foundermental problem because its a natural situation and it affects the world at Large.in other words,it's limit in supply relating to deman
'Economics is about making choices in the presence of scarcity"
manoj Reply
. 'Economics is about making choices in the presence of scarcity" - Dscuss.
describe the producer's scarce resources.. I.e land,Labour,capital and enterprise
Alfhah Reply
short in supply
What are human behaviour?
Regina Reply
the rationality in decision making
how can you describe economic goods in a much better easier way?
Alfhah Reply
any thing that have utility
what is deman and supply
Aruna Reply
Demand can be defined as the ability and willingness to buy commodities in a given price of goods and services in a particular period of time
supply refers to the ability and willingness to offered commodities for sale in a given price of goods and services in a period of time .
Demand can refer to the ability and willingness to purchase a commodity at a giving price and time.
what must the producer do if total costs exceed total revenue
Mmusi Reply
raise price
reduce cost
scarcity resources sample
nawala Reply
what's scarcity
tumelo Reply
resources short in supply
scarcity is excess against human wants.
scarcity is limit in supply relating to demand
shortge of resources .imbalance of wants to resources .
limitation of supply in relation to their demand for commodity
what are the two types of economic theory's?
Lizabeth Reply
i thick it is microeconomic theory and macroeconomic theory. or it can be normative and positive economic theories.
with diagrams show thé change in prices in thé different time period that can result in an increase in demande
Fankam Reply
define momentary period
What is a monopsony?
Allan Reply
monopsony is a situation where only one buyer is available in the market
And with many sellers?
to be more specific, oligopsony is a situation with many sellers but few buyers
Thank you
Researchers demonstrated that the hippocampus functions in memory processing by creating lesions in the hippocampi of rats, which resulted in ________.
Mapo Reply
The formulation of new memories is sometimes called ________, and the process of bringing up old memories is called ________.
Mapo Reply
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Source:  OpenStax, University of georgia concepts of biology. OpenStax CNX. May 28, 2013 Download for free at https://legacy.cnx.org/content/col11526/1.2
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