PLANT (BOTANY(PLANT
BIOLOGY ))
WHAT ARE PLANTS?
WHAT IS THERE PURPOSE?
W
ell plants are living organisms that produce food as
Main goal. This type of process is called AUTOTROPHS.
AUTOTROPHS:-organisms that synthesize their own food from
inorganic substances.
As plants they use photosynthesis process to prepare their own
food.PHOTOSYNTHESIS:- combination of two words :-PHOTON
SYNTHESIS
Well PHOTON:- IS Greece word word meaning “light”
SYNTHESIS:- means reaction between two elements or
compounds.
Looking outside which is covered by plants , flowers &tree you
may notice that some of them blossom there flower and other
do not even have flowers. So plants can be classified as :flowering(ANGIOSPERMS)
And non flowering(GYMNOSPERMS)
In this unit we will be able to study about:-DIVERSTY OF PLANTS
-ANGIOSPERMS & GYMNOSPERMS
-REPRODUCTION OF PLANTS IN FLOWERING PLANTS
P
LANTS vary in size,where they live I.e. in the ground
water bodies so on.plants from
mosses (< 7cm) to the biggest
tree
Like
General Sherman Tree(>100m)
differ. In size. Alge is plant living in water bodies using
photosynthesis.
P
lants not only differ in there size,and where they live
They also differ in the present & absence of flowers where the
flowering plants are also called angiosperms where the non
flowering are called gymnosperms. Now days as science &
botanists discovery there about 390,000 species of plants.
Above 90%(352,000) are flowering plants or angiosperms the
main use of the flowers are for sexual reproduction or flower is
the structure for reproduction and creation of seeds & fruits.
Thus, flower reproduction covers the largest production of seeds
and fruits comparing to gymnosperm plants. Cones that are
found in gymnosperm plants are structure for reproduction.
Plants in different places differ?
Well, yes b/c Altitude(high&lowland)
climate(polar,moderate,tropical),
Soil type,fertility&wetness to dryness(sand,clay,loam)
This difference make plant to live in different places,climate,
Altitude.
A
s we know >90%of discovered plants are flowering
plants. There property is differ from there nonflowering
For instance :-they have flowers as reproductive structure
-have seeds and fruits where the seed is inside the fruit to
make the seed wet.
-use different agents to pollinate (wind,insects like bees)
POLLINATION AGENTS:- it is an agent which is involved in
transfer of pollen grains.
POLLINATION:- the process of transfer of pollen grains.
MAIN PARTS OF ANGIOSPERM PLANTS
We know that many plants have leaf,steam,branch,roots as
main part of plant. We know root that is under the ground or
it is found in the soil so, it helps the plant for photosynthesis
process indirectly. As steam it holds the plant up right . leaf
for photosynthesis is used mainly.
SHOOT SYSTEM:- the above ground part of plant, Including
steam
Leaves
Flower
ROOT SYSTEM:-the underground part of plant, including
-main root
-lateral root
-root hairs
-root cap
STEM
THE stem is the part of plant that is found above the soil or
ground. This part of plant is classified in to two:non woody(herbaceous)
Woody
Main function of stem
- transporting water &minerals from root to other parts of
plants
-holding the shoot system parts upright
-Transporting photosynthetic materials from leaf to other parts
LEAVES
This are the esenical part of plant that are involved in
photosynthesis process to produce their food. They store their
food as a starch.
MAIN IMPORTANT OF LEAVES
-carry out photosynthesis to make food
-Gaseous exchange
-water loss
-store food
MAIN PARTS OF LEAVES
The leaf is made of tissue which are sandwiched between 2
tough layers namely lower and upper epidermis.
EPIDERMIS:-the outer layer of tissue in a plant.
-Commonly the leaf has blade or lamina or the board of leaf
part.
-The petiole or the leafstalk is soft steam like that connects to
the main steam.
-It has epidermal layers that protects the leaf from insects and
pests.
-Among the epidermal cells there is sausage-shaped guard cell.
-Each pair of guard cell from pore called stoma or as plural
stomata.
-gases enters and exits through stomata
-most food production takes place in the photosynthetic cell
which is also known as mesophyll tissue.
-the leaf is mainly is made up of the green pigmet which is
also known as chloroplast.
THE ROOT AND ITS SYSTEM
The root is the important part of the plant that is found
underground and fixes it to the soil to absorbs minerals and
water.
Main function of roots:-Absorbs water and minerals and transport materials to the
plant
-Food storage
-Removing unwanted material from the plant
-Communicating to other plants through there roots.
Main external and internal features of the root
The root system contains:-The main (primary) root:- the main root that first grow from
the base of the plant.
-Lateral roots:-secondary roots that is the branch of the main
root.
-Root hairs :-very fine root that appears like hair branching
from lateral or main root.
-Root tip:-the part of the root which is growing downward into
the soil.
-Root cap:- a very tough part of the root which protects the
growing region of the root tip.
Types of root system
Mainly the root system is grouped in to two
Tap root system:-a single central main root grows deep down
ward into the soil and lateral branches developed sideways.
In this root system :- the main root is wider in diameter
And lateral roots are narrower
A carrot root is best example for this root system
Fibrous root system:-is type of root system which contains many
smaller roots of similar diameters.
Roots of corns are the best example for this root system
Internal features of roots
The outer layer of root is covered by epidermis where as the
internal is covered by cortex. The transport components which
is also known as vascular bundles contains the xylem and
phloem.
Vascular bundles :-food and water transporting tissue in
higher plants.
Cortex:- the outer layer of tissue immediately below the
epidermis of root.
Xylem:- vascular tissue that conveys water and dissolved
minerals from the roots to the rest of the plant and also
provides physical support.
Phloem:-is the living tissue in vascular plants that transport
the soluble organic compounds made during photosynthesis.
Monocotyledons
And
Dicotyledon
Cotyledon is leaf -like structure in seeds serving as stored food
for embryo in seeds
So, when we say mono and dicotyledon we are mentationing
the number of cotyledon for mono:-1for di:-2
Monocots:-there about 65000 different species across the world
For instance teff,maize,wheat,barley etc are mono in cots.
Dicots:-there about 170000 different species in the whole
world as discovery. Of example:- sunflower,beans,peas
ANGIOSPERM plants are reproduced sexual and asexual.
Sexual reproduction:-type of reproduction which two parents
are involved as a union of gamete.
Asexual reproduction:- type of reproduction only one parent
involving with out the union of gamete.
Vegetative propagation
In asexual reproduction in plants there is no need of flowers
and other reproduction structure. For the method only the
vegetative part or body of plant is needed to produce there
offspring.
In asexual:-a single organism is involved
There is no production of gamete
Offspring produced are genetically identical
Vegetative propagation can be artificial or naturally.
Artificial Vegetative propagation:- this propagation is done by
humans through cutting there stem,grafting,layering,etc
Natural Vegetative propagation:- this process is done by the
parent plant which is mainly involved through the steams like
rhizomes,corms,suckers soon.
Types of vegetative
Propagation
For instance, we will see 3 propagation but first lets see about
buds.
a small lateral or terminal protuberance on the stem of a plant
that may develop into a flower, leaf, or shoot. 2 : something not
yet mature or at full development: such as. a : an incompletely
opened flower.is called buds.
1) stem cutting
It it process in which the stem is cut down diagonally from the
plant take to the soil and planted diagonally.
This practice is done for many plant like:-rose,