MORPHOLOGY OF ROOT. STEM. LEAF AND THEIR MODIFICATIONS.12 Flashcards
Example of Annual plants;
Yam, maize and beans
Examples of biennial plants
They are usually tubers;Carrot and onions
Example of perennial plant
Cana lily,African never die or sensitive plant And orange.
Examples of aquatic plants
Water spinach and water hyachyacinth
Example of creeping plant
Broad leave carpent grass
Example of a climber
morning glory weed
What are biennials plants?
plants which live (i.e complete their life cycle) within two growing seasons.
Types of roots system.
1.Primary system ; is developed from the embryonic plant as the radicle of the seedling.
2.Adventitious roots system ; develop from superficial tissues other than the embryonic radicle
Types of primary root system?
1.Fibrous; after the production of the primary root, other roots of equal size emerge from the same point,
2.Taproot; limited to a single large persistent growing root
What’s the portion of plant that is positively geotrophic
Roots
Types of adventitious root system?
1.Fascicled roots:Tuberous roots in cluster. For food storage
2.Fusiform roots: Tuberous roots swollen at the middle and taper at both ends. For food storage
3.Buttress roots: thick and dense roots which arise from the base of a tree truck above soil and spread wide on the ground.
4.Pneumatophore roots:they grow upwards. The roots functions as site for oxygen intake (gaseous exchange).
5.Props roots: They grow above the ground usualy out of the lower node and growing downward into soil.For Support
6.Reproductive roots: roots of some shrubs &trees. new plant grow vegetatively from root of mother plant.
7.water root: roots a r e too short to reach a substrate so absorb nutrients form the water
Another type for fusiform when that the middle is round is called
Napiform
Example of water roots?
Water lettuce
Example of plant with reproductive roots:
Guava
Example of Prop roots
Maize, bamboo,Riverside Screwpine and bayan trees
Example of pneumonatophore roots
Red mangrove and white mangrove
Example of Buttress root
Indian almond aka Ēbelebo
Example of fusiform
Carrot and weed tuber
Example of fasicicled
Cassava
Stem occurs underground as;
Rhizomes,Stolons,Corms and bulb
How does Stem differs from root?
the presence of nodes in stem
Stem are divided into
strong and weak stem
Type of stem, explain and there examples:
1.Columnar:Erect,tough,stout(thick) and covered with a layer of cork e.g mango
2.Culm:jointed,solid node and hallow internode e.g Bamboo
3.Scape:Underground stem with erect unbranded aerial shoot e.g Banana
4.Creepers:forms new roots and shoots at the nodes e.g Sourgrass
5.Climbers:Attach themselves to an erect neighbouring plant e.g bottle gourd
What’s a bud?
It’s a immature shoot with anumber of miniature tender leaves
What are the types of buds and explain?
1.Terminal bud: A bud that occurs at the apex(tip) of a stem
2.Axillary bud: A bud that occurs at the axil of the leaves
The bud is protected by?
The bud scales
What’s a Node and Antinode ?
1.Node: A point where leaf or branches develop from.
2.Anti node: space between two successive nodes
what’s a Leaf scar?
mark left on a twig or stem where the petiole of a leaf was attached
What’s a vascular bundle scar?
a small dot, discoloration, or raised bump on the surface of a leaf scar. It is formed when the vascular bundles break off at the point where the leaf was attached to the stem
What’s a Terminal bud scale scar?
A circular marking on a stem that marks the former location of a terminal bud.
What’s a lenticels
Small pores in the bark of woody stems and which allow gases to enter and leave the interior of a stem.
Function of branching in stems?
1.Spread of shoot system
2.For separation of function between branches, where some may be vegetative and others reproductive
Types of branching
1.Lateral branching
2.Dichotomous branching
What’s the most common mode of branching in spermatophyte?
Lateral branching.
Types of branches;
- dichotomous (originating at the terminal bud like the letter Y).
- lateral (from side to side)
Types of lateral branch;
- monopodial or racemose: Each branch arises in the axil of a leaf while the terminal bud continues its upward stem growth e.g pine
- sympodial or cymose: The terminal bud stop growing probably be due to the formation of a flower at that point, and axillary shoots continue growth of the shoot from these lower axils.
Sympodial branching is divided into two types: uniparous or monochasial, which has one lateral bud; biparous or dichasial, which has two lateral buds.
Examples of uniparous and biparous respectively
1.The wild vine
2.The temple tree
Example of sympodial and monopodial;
1.water leaf
2.pine
Stems are modified for what functions?
(1)Reproduction (2) Photosynthesis (3) Protection (4) Storage (5) Support.
Stems for vegetative reproduction
1.Rhizome
2.Corm
3. Bulb
4.Bulbil
5.Stolon(runners)
5.Suckers
6.Offset
Example of reproductive stem that helps in perennation
Rhizome, corm, bulb and stolon
Which type of vegetative stem arise from the node ?
Rhizome and stolon
What’s a Rhizome:
Horizontal underground growing stem E.g. Elephant grass, Canna lily, Ginger
What’s a Corm:
vertical thick, short and swolen underground stem with dry scaly leaves. E.g. Cocoyam
What’s a Bulb:
a short or much reduced nearly flattened stem with a terminal bud. thick fleshy & scaly leaves and adventitious root. E.g Onion,garlic
What’s a Bulbil:
auxiliary buds which grow above the ground in Axli of leaves. E.g wild yam and pineapple.
What’s a Stolon(runners):
Horizontal growing stem above the ground surface. E.g. couch grass
What’s a Suckers:
short branch of a stem arising from underground stem. E.g plantain
What’s a Offset:
short lateral shoots bearing clustered leaves at the tips and are capable of taking roots as plant daughters when seprated from the parent plant.E.g water hyacinth
What’s stem for photosynthesis:
Cladode and Philloclade
Storage stem and their storage products have:
1.water=cladode
2.food=Tubers,Rhizome and corms
Between propagation and storage the main function of rhizome in most grasses is ?
Propagation
What’s the 3 difference between tuber and rhizome ?
- New tuber proceeds from a shoot produced by feeding on and using up the other tuber while A rhizome is produced from the extension of an old rhizome got by means of an auxiliary bud or a terminal bud.
2.Tuber is not uniform in thickness and does not possess adventitious root while rhizome is uniform in thickness and possesses adventitious root
3.Tuber are usually lateral branches formed by the main aerial shoot and last for one season while a rhizome is the main shoot of the plant and exhibit continuous growth
the process by which modified stem coiling round an object for support is
Circum nutation
What’s a twiner
These are plants that climb nearby objects by coiling around them
What is Stem-tendril-assisted climbers ?
Plants with whip-like tendrils; they make contact with objects and help the plants climb on them.
What’s scrambles ?
Plants that use take support by means of hook
What’s the main lateral organ of a green plant
Leaf
The main characteristic of any leave is
It must arise from a node and poses bud on its axil
What’s a Leaf Blade (Lamina):
The lamina is a thin and wide laver(broad portion) of the leaf with a high surface area, to allow maximum absorption of light energy.
What is a Mid-rib?
both a conducting and supporting (strengthening) structure of the leaf
What’s a petiole ?
A leaf stalk which holds the leaf blade and position it well enough to receive enough light.
A leaf which does not have petiole is
sessile
A leaf which have petiole is
Petiolate
Types of leaves
1.Simple leaf
2.Compound leaf
What’s :
(1) A simple leaf
(2) A Compound leaf
- It is not divided into leaflets
- It is divided into many leaflets, attached to the mid vein and having its stalk.
Simple leaf is classified on the basis of
- MARGINS: Entire, Dentate, serrate, Spiny, cleft.
2.:SHAPE: Linear, Lanceolate, Oblong, Cordate, Spatulate, Rotund, Sagittate
What’s an Entire leaf and an example
Leaves that are smooth, not toothed or cut anywhere along its entire length e.g. Black velvet tamarind(Dalium guineense)
What’s an Dentate leaf and an example
Toothed leaves with sharp spreading teeth e.g China grass and tropical nettle weed.
What’s a serrate leaf and an example ?
Saw-toothed leaves pointing towards the leaf apex e.g the china rose
What’s a spiny leaf and an example
Margin have spiny projections. E.g lemon verbena
What’s a cleft leaf and an example
Toothed with rounded tooth e.g The resurrection play (bryophyllum pinnatum)
What’s a Linear leaf and it example?
long, slender, Narrow and 5times as long as it is broad. Eg. Bull grass
What’s a Lanceolate leaf and it example?
Narrow with the broadest point at the base and thinnest point at the apex. E.g Bamboo
What’s an Oblong leaf and it example?
rounded at each end with parallel sides. E.g Banana and plantain
What’s a cordate leaf and it example?
A leaf with an upside down love shape e.g sweet potato
What’s a spatulate leaf and it example?
it has broad apex and narow base. E.g sundew
What’s a Rotund leaf and it example?
Leaf is circular in shape. E.g water lily
What’s a sagittate leaf and it example?
Leaf with arrow head shape . E.g morning glory plant
Apex of a leaf can be described as;
1.Acuminate:Tapering point
2.obtuse: blunt rounded
3.Cuspidate: Sharp spiny
4.Truncate: Broad blunt
5.Emaginate: indented at the end of mid rib
6.mucornate:mid-rib prolonged into a small point.
Compound leaf are divided into what types and examples
1.pinnately compound leaf
2.palmate compound leaf
Pinnate leaves can be classified into:
1.Unipinnate paripinnate leaf
2. Unipinnate imparinnate leaf
3.Bipinnate leaf
4. Thrice pinnate leaf
Arrangement of leaves on shoot:
1.Opposite phyllotaxy
2.Alternate phyllotaxy
3.whorled phyllotaxy
4. Mosaic phyllotaxy
5. Equitant phyllotaxy
What’s an Opposite phyllotaxy and example?
Two leaves on a given plane occur on nodes directly opposite each other e.g guava
What’s an Alternate phyllotaxy and example
Each node occurring on a different plane on either side of the stem. E.g Hibiscus- china- rose
What’s a whorled phyllotaxy and example?
When More than 2 leaves are arranged in circular manner around a node e.g Allamanda
What’s a Mosaic phyllotaxy and example?
Leaves crowded at the top most part of a stem in order to get maximum supply of sunlight. E.g Acalypha grandis
What’s an Equitant phyllotaxy and example?
When Leaves form a cluster at the ground level of the plant e.g pineapple
Leaves modified for Protection purposes consist of:
1.Stipulate leaves
2.scale leaves
3. Sensitive leaves
Leaves modified for support purposes consist of:
1.Tendril
2. Leaf base
3.Petiole support
Purpose for modification of leaves
1.Protection
2. Reproduction
3. Storage
4. Attraction to pollinators
5. Support
What’s the most distinguishing feature between the angiosperm and the other organisms is
The flower
What’s the sporophyll of a plant
The flower.
What’s the micro- and mega-sporophyll of a plant
Micro=Stamen
Mega=pistil
What’s called the essential part of a flower?
The reproductive part(the stamen and pistil)
What’s called the accessory floral part of a flower ?
The perianth(Petal and sepals)
What’s a the description of typical flower?
Part of plant responsible for sexual reproduction and consist of cyclic arrangement of five floral parts
Sepals are collectively called called
calyx
Petals are collectively called called
Corolla
The stamen are collectively called called
Androecium(the male reproductive microsporophyll)
The pistils are collectively called called
Gynoecium (the female reproductive megasporophyll)
The gynoecium consist of
an enlarged basal portion, the ovary, which contains one or more ovules, and a receptive surface for the pollen called the stigma which is connected to the ovary by an elongated style.
What’s inflorescence?
The arrangement of flowers on the shoot of the plant
The 2 types of inflorescence are ?
racemose (indefinite) or cymose (definite).
The inflorescences are branched with the main axis known as
peduncle
What’s a racemose inflorescence?
the youngest flowers are found nearest the apex of the inflorescence while the older ones are below.
What is a racemose inflorescence?
the youngest flowers are found nearest the apex of the inflorescence while the older ones are below.
What’s a cymose inflorescence ?
the youngest flowers are borne below the oldest and opening of flowers accur from the lower to the upper part of the inflorescence.
What’s a receptacle?
It is the swollen end of the pedicel on which the floral parts are borne
Types of racemose
1.Raceme:
2.Spike:
3.Corymb:
4.Umbel:
5.Capitulum: