The document discusses various types of root modifications in plants. It describes storage roots, which become swollen from accumulating excess food. Storage roots can develop from tap roots or adventitious roots. Velamen roots are modified adventitious roots of epiphytic plants that absorb water from the air. Respiratory roots in mangroves have pores that allow for gas exchange and respiration in oxygen-deficient soil. Nodular roots in legumes form symbiotic nodules inhabited by nitrogen-fixing bacteria. Parasitic roots establish connections to host plants to absorb water and nutrients.
Du Mediaplanning au Content Management - Présentation Coca-Cola au Petit Club...Petit Web
Présentation Coca-Cola au Petit Club du 7 janvier 2014. Compte-rendu : http://www.petitweb.fr/actualites/brand-publishing-les-7-regles-dor-de-cetelem-coca-cola-et-m6/
Succession “Losers”: What Happens to Executives Passed Over for the CEO Job?
By David F. Larcker, Stephen A. Miles, and Brian Tayan
Stanford Closer Look Series
Overview:
Shareholders pay considerable attention to the choice of executive selected as the new CEO whenever a change in leadership takes place. However, without an inside look at the leading candidates to assume the CEO role, it is difficult for shareholders to tell whether the board has made the correct choice. In this Closer Look, we examine CEO succession events among the largest 100 companies over a ten-year period to determine what happens to the executives who were not selected (i.e., the “succession losers”) and how they perform relative to those who were selected (the “succession winners”).
We ask:
• Are the executives selected for the CEO role really better than those passed over?
• What are the implications for understanding the labor market for executive talent?
• Are differences in performance due to operating conditions or quality of available talent?
• Are boards better at identifying CEO talent than other research generally suggests?
ROOTS - Basics, Function, Various Parts - Maturation, Root-Hairs, Elongation,...ASWIN ANANDH
Detailed description about roots, Functions of roots, Various parts of roots - Region of Maturation, Region of Root-Hairs, Region of Elongation, Region of Cell-Division, Root cap, Types of roots - Taproot System, Adventitious Roots, Modification of Roots for storage of food, Types of Modification - Conical roots, Fusiform roots, Napiform roots; Adventitious root modified into Tuberous roots, Fasciculated tuberous roots, Palmated tuberous roots, Annulated roots; Modification for Support - Climbing Roots, Stilt roots, Columnar roots; Modification for Special functions - Respiratory roots or Pneumatophores, Sucking Roots, Photosynthetic Roots, Epiphytic Roots or Assimilatory Roots - Clinging Roots, Aerial Roots, Nodulated Roots or Root Tubercles & Uses of Roots.
The lecture notes provide an understanding of the different types of roots and their morphology. different types of roots have been clearly explained with their pictures and labeled diagrams included, enjoy the reading
Asangalwisye deo
SJUT
This is a three chapter review for the Agriculture Major Admission Test conducted by the College of Agriculture of Cavite State University, the topicsare: Plant Bilogy, Crop and Agriculture and basic Physiological processes of plants. Credits to all my sourceswhich include lecture notes from our faculty, online sources and books published in the Republic of the Philippines.
Du Mediaplanning au Content Management - Présentation Coca-Cola au Petit Club...Petit Web
Présentation Coca-Cola au Petit Club du 7 janvier 2014. Compte-rendu : http://www.petitweb.fr/actualites/brand-publishing-les-7-regles-dor-de-cetelem-coca-cola-et-m6/
Succession “Losers”: What Happens to Executives Passed Over for the CEO Job?
By David F. Larcker, Stephen A. Miles, and Brian Tayan
Stanford Closer Look Series
Overview:
Shareholders pay considerable attention to the choice of executive selected as the new CEO whenever a change in leadership takes place. However, without an inside look at the leading candidates to assume the CEO role, it is difficult for shareholders to tell whether the board has made the correct choice. In this Closer Look, we examine CEO succession events among the largest 100 companies over a ten-year period to determine what happens to the executives who were not selected (i.e., the “succession losers”) and how they perform relative to those who were selected (the “succession winners”).
We ask:
• Are the executives selected for the CEO role really better than those passed over?
• What are the implications for understanding the labor market for executive talent?
• Are differences in performance due to operating conditions or quality of available talent?
• Are boards better at identifying CEO talent than other research generally suggests?
ROOTS - Basics, Function, Various Parts - Maturation, Root-Hairs, Elongation,...ASWIN ANANDH
Detailed description about roots, Functions of roots, Various parts of roots - Region of Maturation, Region of Root-Hairs, Region of Elongation, Region of Cell-Division, Root cap, Types of roots - Taproot System, Adventitious Roots, Modification of Roots for storage of food, Types of Modification - Conical roots, Fusiform roots, Napiform roots; Adventitious root modified into Tuberous roots, Fasciculated tuberous roots, Palmated tuberous roots, Annulated roots; Modification for Support - Climbing Roots, Stilt roots, Columnar roots; Modification for Special functions - Respiratory roots or Pneumatophores, Sucking Roots, Photosynthetic Roots, Epiphytic Roots or Assimilatory Roots - Clinging Roots, Aerial Roots, Nodulated Roots or Root Tubercles & Uses of Roots.
The lecture notes provide an understanding of the different types of roots and their morphology. different types of roots have been clearly explained with their pictures and labeled diagrams included, enjoy the reading
Asangalwisye deo
SJUT
This is a three chapter review for the Agriculture Major Admission Test conducted by the College of Agriculture of Cavite State University, the topicsare: Plant Bilogy, Crop and Agriculture and basic Physiological processes of plants. Credits to all my sourceswhich include lecture notes from our faculty, online sources and books published in the Republic of the Philippines.
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Macroeconomics- Movie Location
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Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
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Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
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The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
1. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
Root
Very Short Answer Questions
1. Give the scientific names of two plants which store food in their tap roots. How
do they differ in their shapes?
Ans: Raphanussativus – fusiform roots with broad middle region and tapering
towards tip and base. Daucuscarota – Conical roots that are broad at the base and
gradually taper towards the tip.
2. What are fasciculated roots? Give two examples.
Ans: It is a tuft of storage adventitious roots. Ex: Asparagus, Dahlia, Ruelliatuberosa
3. What is epiphytic habit? Which roots help it?
Ans: It is growing of a plant on some other plant for shelter to expose its foliage to the
sun to get proper amount of sunlight to perform photosynthesis. Velamen roots or
Epiphytic roots help for such habit.
4. Define root crops. What would happen if the root crops are harvested at the end
of second year?
Ans: Plants grown by farmers for their roots are called as Root crops. These plants are
biennnials. They synthesize and store the excess food in their roots. In the second year
they utilize the stored food for reproduction. If harvested at the end of second year,
either less or no food materials are left out in the roots.
5. What are assimilatory roots? Give two examples.
Ans: Modified adventitious roots that become green colored and perform
photosynthesis are called as assimilatory roots. Ex: Taeniophyllum, Trapa,
Tinosporacordifolia.
6. Compare photosynthetic roots of Tinospora with those of Trapa.
Ans: In Tinospora, the photosynthetic roots are aerial and in Trapa they are
underwater.
7. What is complete root parasite? Give an example.
Ans: Achlorophyllus, usually leafless or with scale leaved parasite which establishes
haustorial connection with both xylem and phloem of host root to absorb both mineral
water and organic food is called as complete root parasite. Ex: Rafflesia,
Balanophora, Orobanche.
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2. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
Short answer Questions
1. Mention the characteristics of a root system. Add a note on its functions.
Ans: Characters of a Root system
1. Root with its appendages is called as root system. The roots are usually positively
geotropic (except pneumatophores).
2. Root is not differentiated into nodes and internodes.
3. Leaves and normal buds are absent.
4. Root is non-chlorophyllous and brown colored.
5. Lateral roots are formed endogenously in acropetal manner.
6. Apices of roots are protected by Root cap. In free floating hydrophytes root
pockets are present.
7. Roots have unicellular epidermal outgrowths called as root hairs. These are short
lived, exogenous and developed acropetally.
Functions:
1. Root anchors the plant at proper place in the soil.
2. It absorbs water and minerals from the soil or substratum.
3. It conducts the absorbed mineral water to the aerial system of the plant.
2. Define root. Write briefly on the types of root system.
Ans: Root is underground axis of the plant usually developed from radicle of embryo.
There are two types of root systems. They are Tap root system and adventitious root
system.
1. Tap Root system: It is developed from radicle of embryo. It has a directly growing
tap root from which the endogenously developed lateral roots are arranged in
acropetal manner and grow obliquely into the soil. It is commonly seen in Dicots.
2. Adventitious root system: This root system is developed from any part of the pant
other than radicle. It is usually developed from base of the stem as fiber like
structures. Hence it is also called as fibrous root system. It is commonly found in
Monocots.
3. Write short notes on Storage roots.
Storage Roots: These are also known as tuberous roots. These modified roots become
swollen due to accumulation of excessive food materials.
Storage Tap roots: If storage root is formed from tap root system, usually the tap
root stores food attains a specific shape. It is conical in Daucus, fusiform in
Raphanussativus, napiform in Beta vulgaris.
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3. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
Storage adventitious roots: Only one storage irregularly shaped root arises at
every node in Ipomoea batatus. A group of storage adventitious roots arise at the
base of stem known as fasciculated roots in monocot Asparagus and in dicots like
Ruelliatuberosa and Dahlia tuberosa.
/ƉŽŵŽĞĂ ďĂƚĂƚƵƐ
ƐƉĂƌĂŐƵƐ
In most of the storage roots starch is stored. But in Beta vulgaris, it is Sugar and in
Dahlia it is inulin.
Plants grown by farmers for their roots are called root crops. Root crops are
biennials. They store the synthesized food in their roots during first year and
utilize it in the second year for flowering and seed setting. Hence the root crops
must be harvested at the end of first year.
4. Write short notes on velamen roots.
Ans: Epiphytic roots: Plants that grow on some other plant for shelter are called
as epiphytes. These plants usually belong to families Orchidaceae and Aroideae.
These plants are commonly seen in tropical evergreen forests. They inhabit on top
braches of host tree to get proper amount of sunlight to perform photosynthesis.
Modified aerial adventitious roots seen in such plants are called as epiphytic roots.
Epiphytes have two types of roots. They are clinging roots and velamen roots.
Clinging roots are relatively short, slender, branched and enter into the crevices of
host branch to fix the plant on the host branch. They also absorb mineral water
collected in the crevices. Velamen roots are elongated, stout, branched without
root hairs and freely hang in the air. They have dead hygroscopic multiple
epidermis known as velamen which helps in absorbing atmospheric moisture by
imbibition. Ex: Vanda, Bulbophyllum
ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
4. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
5. What are respiratory roots? Explain their role in mangrove plants.
Ans: Respiratory roots: These are usually seen in Mangroves like Avicennia and
Rhizophora which grow in water logged muddy soils of estuaries. Underground
roots of such plants face oxygen deficient conditions. In these plants some of the
lateral roots of underground roots become aerial, have minute lenticular openings
called pneumathodes, through which the air enters into the root and after
respiration the CO2 comes out through the same pores. In this way these help in
respiration. Hence these are called as Respiratory roots or Pneumatophores or
Breathing roots. Adventitious breathing roots are seen in a free floating
hydrophyte called as Jussiaea whose roots are spongy and porate.
6. What are nodular roots? What is their significance?
Nodular roots: These are modified roots of tap root system with swollen
structures called nodules. These are inhabited by a bacterium Rhizobium in
leguminous plants. This bacterium fixes atmospheric nitrogen into ammonia and
supplies it to the plant and in return it takes organic food from host cortical cells.
In this way these modified roots show symbiosis. Nodules have a pigment called
Leg.haemoglobin which helps in controlled supply of oxygen to the bacterium.
Because of these root nodules, leguminous plants are used in crop rotation and as
green manure. Ex: Arachis, Dolichos.
7. Write short notes on parasitic roots.
Ans: Parasitic roots: Plants that obtain either only mineral water or both mineral
water and organic food from other plants are called as parasitic plants. Modified
ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
5. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
roots seen in such plants are called as parasitic roots or Haustorial roots. If the
plant establishes haustorial connection with the root of host it is called as root
parasite and that one with the stem as stem parasite. If the parasite is
photosynthetic, establishes haustorial connection only with the xylem of the host,
it is called as partial parasite. If it is achlorophyllous, without leaves or with scale
leaves, establishes haustorial connection with both xylem and phloem of the host
it is called as complete parasite. These parasites are as follows.
1. Complete stem parasite. Ex: Cuscuta
2. Complete root parasite. Ex: Orobanche, Rafflesia, Balanophora.
3. Partial stem parasite. Ex: Viscum, Loranthus
4. Partial root parasite. Ex: Santalum album, Striga
Long Answer Questions
1. Describe various types of Root modifications
Ans: The permanent change in the root or its part to perform either only additional
functions or both additional and normal functions that suit for the survival of the plant
in the new conditions is called as Root modification. The modified roots are as
follows.
1. Storage Roots: These are also known as tuberous roots. These modified roots
become swollen due to accumulation of excessive food materials.
Storage Tap roots: If storage root is formed from tap root system, usually the tap
root stores food attains a specific shape. It is conical in Daucus, fusiform in
Raphanussativus, napiform in Beta vulgaris.
Storage adventitious roots: Only one storage irregularly shaped root arises at
every node in Ipomoea batatus. A group of storage adventitious roots arise at the
base of stem known as fasciculated roots in monocot Asparagus and in dicots like
Ruelliatuberosa and Dahlia tuberosa.
ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
6. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
/ƉŽŵŽĞĂ ďĂƚĂƚƵƐ
ƐƉĂƌĂŐƵƐ
In most of the storage roots starch is stored. But in Beta vulgaris, it is Sugar and in
Dahlia it is inulin.
Plants grown by farmers for their roots are called root crops. Root crops are
biennials. They store the synthesized food in their roots during first year and
utilize it in the second year for flowering and seed setting. Hence the root crops
must be harvested at the end of first year.
2. Epiphytic roots: Plants that grow on some other plant for shelter are called as
epiphytes. These plants usually belong to families Orchidaceae and Aroideae.
These plants are commonly seen in tropical evergreen forests. They inhabit on top
braches of host tree to get proper amount of sunlight to perform photosynthesis.
Modified aerial adventitious roots seen in such plants are called as epiphytic roots.
Epiphytes have two types of roots. They are clinging roots and velamen roots.
Clinging roots are relatively short, slender, branched and enter into the crevices of
host branch to fix the plant on the host branch. They also absorb mineral water
collected in the crevices. Velamen roots are elongated, stout, branched without
root hairs and freely hang in the air. They have dead hygroscopic multiple
epidermis known as velamen which helps in absorbing atmospheric moisture by
imbibition. Ex: Vanda, Bulbophyllum
3. Photosynthetic roots: Modified adventitious roots which become green colored
and perform photosynthesis are called as Photosynthetic roots or Assimilatory
roots. These are usually seen in epiphytes like Taeniophyllum in which the roots
are flat ribbon like green velamen roots. Assimilatory roots are also seen in a
climber called as Tinosporacordifolia. A hydrophyte called Trapa has underwater
photosynthetic roots.
ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
7. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
4. Respiratory roots: These are usually seen in Mangroves like Avicennia and
Rhizophora which grow in water logged muddy soils of estuaries. Underground
roots of such plants face oxygen deficient conditions. In these plants some of the
lateral roots of underground roots become aerial, have minute lenticular openings
called pneumathodes, through which the air enters into the root and after
respiration the CO2 comes out through the same pores. In this way these help in
respiration. Hence these are called as Respiratory roots or Pneumatophores or
Breathing roots. Adventitious breathing roots are seen in a free floating
hydrophyte called as Jussiaea whose roots are spongy and porate.
5. Nodular roots: These are modified roots of tap root system with swollen
structures called nodules. These are inhabited by a bacterium Rhizobium in
leguminous plants. This bacterium fixes atmospheric nitrogen into ammonia and
supplies it to the plant and in return it takes organic food from host cortical cells.
In this way these modified roots show symbiosis. Nodules have a pigment called
Leg.haemoglobin which helps in controlled supply of oxygen to the bacterium.
Because of these root nodules, leguminous plants are used in crop rotation and as
green manure. Ex: Arachis, Dolichos.
ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
8. ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ
6. Parasitic roots: Plants that obtain either only mineral water or both mineral water
and organic food from other plants are called as parasitic plants. Modified roots
seen in such plants are called as parasitic roots or Haustorial roots. If the plant
establishes haustorial connection with the root of host it is called as root parasite
and that one with the stem as stem parasite. If the parasite is photosynthetic,
establishes haustorial connection only with the xylem of the host, it is called as
partial parasite. If it is achloro phyllous, without leaves or with scale leaves,
establishes haustorial connection with both xylem and phloem of the host it is
called as complete parasite. These parasites are as follows.
5. Complete stem parasite. Ex: Cuscuta
6. Complete root parasite. Ex: Orobanche, Rafflesia, Balanophora.
7. Partial stem parasite. Ex: Viscum, Loranthus
8. Partial root parasite. Ex: Santalum album, Striga
ǁǁǁ͘ƐĂŬƐŚŝĞĚƵĐĂƚŝŽŶ͘ĐŽŵ