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 Photos depict a variety of nuts in their shells, an apple, raspberries and a pineapple.
There are four main types of fruits. Simple fruits, such as these nuts, are derived from a single ovary. Aggregate fruits, like raspberries, form from many carpels that fuse together. Multiple fruits, such as pineapple, form from a cluster of flowers called an inflorescence. Accessory fruit, like the apple, are formed from a part of the plant other than the ovary. (credit "nuts": modification of work by Petr Kratochvil; credit "raspberries": modification of work by Cory Zanker; credit "pineapple": modification of work by Howie Le; credit "apple": modification of work by Paolo Neo)

Fruits generally have three parts: the exocarp    (the outermost skin or covering), the mesocarp    (middle part of the fruit), and the endocarp    (the inner part of the fruit). Together, all three are known as the pericarp    . The mesocarp is usually the fleshy, edible part of the fruit; however, in some fruits, such as the almond, the endocarp is the edible part. In many fruits, two or all three of the layers are fused, and are indistinguishable at maturity. Fruits can be dry or fleshy. Furthermore, fruits can be divided into dehiscent or indehiscent types. Dehiscent fruits, such as peas, readily release their seeds, while indehiscent fruits, like peaches, rely on decay to release their seeds.

Fruit and seed dispersal

The fruit has a single purpose: seed dispersal. Seeds contained within fruits need to be dispersed far from the mother plant, so they may find favorable and less competitive conditions in which to germinate and grow.

Some fruit have built-in mechanisms so they can disperse by themselves, whereas others require the help of agents like wind, water, and animals ( [link] ). Modifications in seed structure, composition, and size help in dispersal. Wind-dispersed fruit are lightweight and may have wing-like appendages that allow them to be carried by the wind. Some have a parachute-like structure to keep them afloat. Some fruits—for example, the dandelion—have hairy, weightless structures that are suited to dispersal by wind.

Seeds dispersed by water are contained in light and buoyant fruit, giving them the ability to float. Coconuts are well known for their ability to float on water to reach land where they can germinate. Similarly, willow and silver birches produce lightweight fruit that can float on water.

Animals and birds eat fruits, and the seeds that are not digested are excreted in their droppings some distance away. Some animals, like squirrels, bury seed-containing fruits for later use; if the squirrel does not find its stash of fruit, and if conditions are favorable, the seeds germinate. Some fruits, like the cocklebur, have hooks or sticky structures that stick to an animal's coat and are then transported to another place. Humans also play a big role in dispersing seeds when they carry fruits to new places and throw away the inedible part that contains the seeds.

All of the above mechanisms allow for seeds to be dispersed through space, much like an animal’s offspring can move to a new location. Seed dormancy, which was described earlier, allows plants to disperse their progeny through time: something animals cannot do. Dormant seeds can wait months, years, or even decades for the proper conditions for germination and propagation of the species.

 Part A shows a dandelion flower that has seeded.  Part B shows a coconut floating in water.  Part c shows two acorns.
Fruits and seeds are dispersed by various means. (a) Dandelion seeds are dispersed by wind, the (b) coconut seed is dispersed by water, and the (c) acorn is dispersed by animals that cache and then forget it. (credit a: modification of work by "Rosendahl"/Flickr; credit b: modification of work by Shine Oa; credit c: modification of work by Paolo Neo)

Section summary

For fertilization to occur in angiosperms, pollen has to be transferred to the stigma of a flower: a process known as pollination. Gymnosperm pollination involves the transfer of pollen from a male cone to a female cone. When the pollen of the flower is transferred to the stigma of the same flower, it is called self-pollination. Cross-pollination occurs when pollen is transferred from one flower to another flower on the same plant, or another plant. Cross-pollination requires pollinating agents such as water, wind, or animals, and increases genetic diversity. After the pollen lands on the stigma, the tube cell gives rise to the pollen tube, through which the generative nucleus migrates. The pollen tube gains entry through the micropyle on the ovule sac. The generative cell divides to form two sperm cells: one fuses with the egg to form the diploid zygote, and the other fuses with the polar nuclei to form the endosperm, which is triploid in nature. This is known as double fertilization. After fertilization, the zygote divides to form the embryo and the fertilized ovule forms the seed. The walls of the ovary form the fruit in which the seeds develop. The seed, when mature, will germinate under favorable conditions and give rise to the diploid sporophyte.

Art connections

[link] What is the function of the cotyledon?

  1. It develops into the root.
  2. It provides nutrition for the embryo.
  3. It forms the embryo.
  4. It protects the embryo.

[link] B

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Questions & Answers

what is an organ
rab Reply
a part of a organism
A group of cell makes organ
Organ is part of the body.
a group of tissues that perform a specific function
What is pseudopodia
Mmesoma Reply
a temporary protrusion of the surface of an ameboid cell for movement and feeding.
This help the animals to move from one place to another
what is the live ?
What is biology?
khan Reply
what is alliminatary canal
i don't know but i wana to laern please tell me
there is something called googling as far as i know
biology_it's science that study of living things
alimentary canal_the whole passage along which food passes through the body from mouth to anus. It includes the esophagus, stomach, and intestines.
is a branch of science whith deals the study of living things
what element in colors purple
Mikaela Reply
what are the function of sympathetic nervous system and parasympathetic nervous system
Ubon Reply
what is preganglionic
don't know
what is reproduction
reproducing specifically : the process by which plants and animals give rise to offspring and which fundamentally consists of the segregation of a portion of the parental body by a sexual or an asexual process and its subsequent growth and differentiation into a new individual.
is the process where by organism produce their new organism of the same species from those who a ready in existence.
what is unicellular cell
unicellular orgnism* meaning consisting of a single cell
How does reproduction take place in human being
Is a single celled organism
What is the Antibiotic
Tamara Reply
antibiotics is any medication that stop the growth of bacteria
what is biomolecules
Lawerence Reply
This is a group of molecules produced by a living organism
thank alot,I had a hard time getting the answer
wat is the meaning of Mr.niger. d
It Reply
Now Mr. Niger Dac M;movement R;respiration N;nutrition G;growth E;excretion R;reproduction D;death A;adaptation C;competition
Sorry.... I;irritability
Mesumbe Reply
Emmanuel Daniel
what is the meaning of Mr Niger?
the meaning of Mr Niger, movement , reproduction , nutrition, inspiration , growth, excretion ,reproduction
Emmanuel Daniel it's Mr NIGER D
and d is for death
Brown Jones ug
state all the elements and their symbols
Taiwo Reply
what types of muscles are found in the heart
Diamond Reply
Cardiac muscle
cardiac or myocardia muscle
cardiac muscles
cardiac muscle
Cardiac muscle
Thank you dear!
please can you tell me the meaning of Mr Niger?
It is an initial to represent life processes of organisms. M means movement, R for reproduction, N stands for nutrition, I for irritability or sensitivity,G means growth , E for excretion and R stands for respiration.
cardiac muscle
what is digestion
Dolla Reply
it is the chemical break down of insoluble food substances such as fatty acid to soluble substances which are then used for body processes
does human being sperm performed in the ovary of goat
sadeeq Reply
levels of ecological study
human sperms contains acid
what is an artery
It is one of the organs of the circulatory system that carries oxygenated blood from the heart to other parts of the body.
artery is type of blood vessel which carries blood away from heart...
how liver destroy red blood cells?
big bang theory was discovered by
Sweety Reply
Georges Lemaître

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