Assignment 1 - Teff (*Eragrostis tef*)

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Questions and Answers

What family does the plant Eragrostis tef belong to?

Brassicaceae

Poaceae (correct)

Fabaceae

Asteraceae

Which of the following characteristics best describes Eragrostis tef?

Deciduous woody shrub

Biennial tree

Perennial vining plant

Annual herbaceous plant (correct)

Where was Eragrostis tef first domesticated?

Egypt

South Africa

Ethiopia (correct)

India

Which part of the Eragrostis tef plant is primarily used for human consumption?

Seeds Signup and view all the answers

What type of climate is most suitable for the growth of Eragrostis tef?

Arid and semi-arid Signup and view all the answers

What was the main issue with common names in plant classification during the Age of Herbals?

A single name could refer to different species or vice versa. Signup and view all the answers

What is the primary distinguishing feature between monocots and eudicots?

Number of cotyledons Signup and view all the answers

What was Theophrastus's contribution to plant classification?

He identified key characteristics to distinguish natural plant groups. Signup and view all the answers

Which of the following describes the root system of monocots?

Short-lived primary root with a fibrous root system Signup and view all the answers

Which of the following statements is true regarding the binomial nomenclature system introduced by Carl Linnaeus?

The species name is made up of two parts: generic name and species epithet. Signup and view all the answers

What was a characteristic of the polynomial nomenclature used before Linnaeus's binomial system?

It often consisted of lengthy descriptive phrases. Signup and view all the answers

Which plant family includes cinnamon and avocados?

Lauraceae Signup and view all the answers

Which of these flower arrangements is typical of eudicots?

Four or five or multiples Signup and view all the answers

Which statement about the magnoliid group is correct?

It predates the divergence of monocots and eudicots Signup and view all the answers

What was one reason for the development of a Latin-based system of nomenclature?

Both A and B Signup and view all the answers

What is NOT a rule of the International Code of Botanical Nomenclature?

The species epithet must always be capitalized. Signup and view all the answers

Which of the following features is NOT characteristic of monocots?

Woody plant form Signup and view all the answers

How did early classification systems differ from modern classification systems?

Early systems were based on observable features rather than evolutionary relationships. Signup and view all the answers

Which of these economic plants belongs to the Piperaceae family?

Black pepper Signup and view all the answers

What is a significant feature of the Victoria Water Lily that aids in its survival?

It has maximized its surface area for light absorption. Signup and view all the answers

Which of the following statements about the evolutionary relationship of flowering plants is true?

Recent advances in molecular biology have improved understanding of phylogenetic relationships. Signup and view all the answers

According to the theories of Engler and Hooker, what was proposed about the earliest evolved flowers?

Engler emphasized small, wind-pollinated flowers, whereas Hooker emphasized large flowers. Signup and view all the answers

What is an example of a species that has adapted to survive in foggy conditions?

Giant Senecio Signup and view all the answers

Which adaptive characteristic is common among baobab trees in Madagascar?

They possess thick trunks. Signup and view all the answers

Which classification system emphasizes environmental variation and variability in traits?

Phenetic classification systems Signup and view all the answers

What does the term 'primitive characteristics' refer to in the context of flowering plant evolution?

Features that evolved early in the plant lineage. Signup and view all the answers

Azarella compacta is primarily found in which region?

South American Andes Signup and view all the answers

What does a short form of a generic name, like P.glauca, represent in a manuscript?

An abbreviation used for repeated mentions Signup and view all the answers

Why is the biological species concept difficult to apply in practice for plants?

Challenging to assess interbreeding due to spatial separation. Signup and view all the answers

What is one major problem with using morphology to classify plant species?

Environmental conditions strongly influence morphological traits. Signup and view all the answers

What does the presence of fertile hybrids suggest about the biological species concept in plants?

The concept of species as strictly defined groups is flawed. Signup and view all the answers

How does evolution impact plant morphology according to the content?

Evolution can produce dramatic changes based on environmental adaptations. Signup and view all the answers

How does the plant Rafflesia attract pollinators?

By releasing a 'corpse' smell to attract certain insects. Signup and view all the answers

Which of the following is a characteristic of the plant Duckweed?

It is known for its invasive nature and small fruit. Signup and view all the answers

What phenomenon describes the asexual reproduction method used by some plants like dandelion?

Agamospermy Signup and view all the answers

What was the percentage of cultivation in Central America around 7,000 years ago?

15% Signup and view all the answers

Which crop was NOT mentioned as a major agricultural product in Central America by 3,500 years ago?

Rice Signup and view all the answers

Which civilization in Central America is known for intensive irrigation agriculture?

Aztec Signup and view all the answers

What significant agricultural practice was introduced around 2,500 years ago?

Introduction of irrigation Signup and view all the answers

What did the archaeological evidence suggest about the development of agriculture in wetter areas of Central and South America?

It was poorly preserved. Signup and view all the answers

What was a key factor that encouraged human populations to transition from a nomadic lifestyle to agriculture?

A reliable local food supply Signup and view all the answers

How did the domestication of plants impact human society?

Development of permanent settlements Signup and view all the answers

Which part of human activity changed significantly due to the advent of agriculture?

The time spent obtaining food Signup and view all the answers

What led to the change in food supply reliability with the advent of agriculture?

Cultivation of specific crops Signup and view all the answers

Which question is NOT commonly addressed by ethnobotanists and cultural anthropologists regarding agriculture?

What were the impacts of crop species on climate change? Signup and view all the answers

What was a primary factor that led to the development of agriculture in arid regions?

Need for a reliable food supply Signup and view all the answers

Which of the following theories focuses on the role of weeds in the transition to agriculture?

Anderson's theory Signup and view all the answers

What did Carl Sauer hypothesize about human populations and agriculture?

Sedentary lifestyles originated in favorable habitats. Signup and view all the answers

Which archeological site reveals early agricultural practices in Asia Minor?

Jarmo Signup and view all the answers

What type of crops dominated European agricultural practices as they transitioned from Asia Minor?

Rye and oats Signup and view all the answers

Why is the evidence of agricultural development limited in humid environments?

Poor preservation of archaeological materials Signup and view all the answers

What type of environment is noted for the best preservation of archaeological materials?

Arid regions Signup and view all the answers

Around what time does evidence suggest agriculture was commonly practiced in the Americas?

5,000 to 7,000 years ago Signup and view all the answers

Which of the following is NOT identified as a principal center for the origin of agriculture?

North America Signup and view all the answers

What type of agriculture is evident at the Yang-Chao site in Central China?

Irrigated rice fields Signup and view all the answers

What crops began to emerge in the Sahara region around 6,000 years ago?

Sorghum and millet Signup and view all the answers

What is the significance of various archaeological theories regarding agricultural development?

They allow for multiple perspectives on the factors influencing agriculture. Signup and view all the answers

What characteristic is favored by the selection pressures in cereal crops leading to efficient harvesting?

Uniform seed maturation Signup and view all the answers

Which of the following traits results from the selection against clonal axillary shoots in wild grasses?

Compression of tillering Signup and view all the answers

What consequence does the loss of germination inhibitors have for cultivated crops?

Simultaneous germination Signup and view all the answers

Why are seeds that shatter before harvest considered unfavorable in agriculture?

They decrease yield reliability Signup and view all the answers

Which of these factors is NOT a selection pressure affecting the development of agricultural plants?

Varied seed maturation times Signup and view all the answers

What does a reduction in day-length sensitivity indicate for crop plants transported to northern climates?

Increased adaptability to varying light conditions Signup and view all the answers

Which of the following characteristics has NOT been selected for in the evolution of cereal crops?

Greater seasonal variability Signup and view all the answers

What is the primary advantage of polyploidy in plants?

It increases the genetic material available for new traits. Signup and view all the answers

What is the primary concern regarding genetically engineered (GE) crops?

They can hybridize with native plants and impact ecosystems. Signup and view all the answers

Which of the following is a key factor in maintaining genetic diversity for crop development?

Preservation of older plant cultivars. Signup and view all the answers

Which statement correctly differentiates genetic modification from genetic engineering?

Genetic engineering often involves direct genome manipulation, while genetic modification is broader. Signup and view all the answers

Which of the following crops is commonly recognized as a genetically engineered variety?

Corn Signup and view all the answers

What is mutability in the context of crop development?

The frequency at which genetic mutations occur. Signup and view all the answers

What is a significant ecological concern associated with the loss of tropical rainforests?

Reduction in biodiversity and genetic resources. Signup and view all the answers

Which natural event can induce polyploidy in plants?

Colchicine application Signup and view all the answers

How are Brussels sprouts relevant in the discussion of genetic mutations?

They are a natural mutation of cabbage that was propagated. Signup and view all the answers

What advantage do seedlings with higher food reserves have in high-density planting?

They can grow faster and potentially survive to maturity. Signup and view all the answers

What characteristic can weedy species develop to compete with crops?

Seeds that are sized similarly to crop seeds. Signup and view all the answers

Which crop was introduced to Europe from the Americas during the 1600s?

Potatoes Signup and view all the answers

What was one significant consequence of the Green Revolution?

Higher crop yields but increased vulnerability to weather conditions. Signup and view all the answers

What is a consequence of planting monocultures in agriculture?

Higher risk of pathogen outbreaks due to lack of genetic diversity. Signup and view all the answers

Which best describes the process of genetic crossing in plant breeding?

A labor-intensive process to develop new cultivars. Signup and view all the answers

What is a notable example of a crop that resulted from the crossing of wheat and rye?

Triticale Signup and view all the answers

Which characteristic of high-yield crops is often disadvantageous for farmers?

Higher costs associated with inputs like fertilizers. Signup and view all the answers

What problem did the Irish potato famine illustrate regarding monoculture farming?

Monocultures can lead to catastrophic crop failures. Signup and view all the answers

Which of the following plants is native to Africa?

Coffee Signup and view all the answers

What was a significant introduction to Europe during the Arabic colonization of Spain?

Sugar cane Signup and view all the answers

What is one challenge faced by developing nations regarding the Green Revolution?

Access to advanced agricultural technology. Signup and view all the answers

Study Notes

Botanical Information

Belongs to the Poaceae (grass) family.
Type:
- Herbaceous plant.
- Considered an annual.
Native distribution primarily in the Horn of Africa, particularly Ethiopia and Eritrea.

History as a Food Plant

First domesticated in Ethiopia around 4000-1000 BCE.
Most widely grown in Ethiopia, where it is a staple food crop.

Utilization

The edible part of the plant is the seed.
Seeds are ground into flour, which is commonly used to make traditional dishes like injera, a fermented flatbread.
Harvested by cutting the plants at maturity, followed by threshing to separate seeds from chaff.
Seeds can also be processed into porridge or brewed as a beverage.

History of Plant Classification

Plant classification has roots in Ancient Greek times, aimed at developing a natural grouping system.
Key classification questions include the criteria for grouping organisms and the definition of similarity.
Early classification systems were artificial, focused on plant appearance and medicinal properties, not evolutionary relationships.
Theophrastus, a student of Aristotle, established the first plant classification system around 2300 years ago, recognizing families like Pea and Sunflower.
The Age of Herbals (1470-1670) expanded plant knowledge through herbal manuscripts that illustrated plants and their medicinal uses, creating issues with inconsistent common names.
A standardized Latin-based nomenclature emerged to resolve confusion around common names.
Carl Linnaeus simplified plant naming with the binomial system, introduced in Species Plantarum (1753), comprising a generic name and species epithet (e.g., Picea glauca).
The binomial nomenclature is governed by the International Code of Botanical Nomenclature, including rules on capitalization, italicization, and authority designations.

Plant Species

Classification is centered on the species concept, defining a biological species as a group able to interbreed but not with others, producing sterile offspring.
Applying this definition presents challenges in plants due to spatial separation, hybrid fertility, and asexual reproduction in certain species, like the dandelion (agamospermy).
Morphological classification (studying form, structure, and size) is commonly employed, though environmental factors influence plant morphology and may complicate classification.
Morphological plasticity means that plants' forms can change drastically based on environmental conditions; for example, potentilla is light-sensitive.

Evolutionary Relationships of Flowering Plants

Morphologically-based classifications (phenetic systems) use conservative characters while avoiding highly variable traits.
The publication of Charles Darwin's Origin of Species (1859) sparked interest in phylogenetic classification emphasizing evolutionary relationships.
Classification depends on understanding ancestral relationships and defining primitive versus advanced plant features, complicated by poor fossil records.
Two historical theories on flowering plant evolution proposed by Engler and Hooker differ in the complexity and characteristics of early flowers.
The modern consensus aligns with Hooker’s modified view, recognizing 300 to 350 flowering plant families, corroborated by molecular biology advancements.

Flowering Plants: Monocots and Eudicots

Angiosperms are traditionally divided into monocots (one cotyledon) and eudicots (two cotyledons).
Monocots display herbaceous forms, floral parts in threes, linear leaves with parallel veins, and short-lived primary roots.
Eudicots exhibit broad leaves with net veins, floral parts in fours or fives, and often have persistent primary roots forming a taproot.
Recent genetic studies reveal the division into monocots and eudicots is simplistic; a third group, magnoliid Angiosperms, predates their divergence.
Economically significant magnoliid families include:
- Magnoliaceae: horticultural and timber species.
- Lauraceae: spices like cinnamon and avocado.
- Annonaceae: tropical fruits, including soursop and custard apple.
- Piperaceae: black pepper.
- Myristicaceae: nutmeg and timber species.

Domestication of Plants

Occurred approximately 10,000 years ago, transitioning from hunter-gatherer societies to settled agricultural communities.
Hunter-gatherers had limited population due to seasonal food supplies, necessitating a nomadic lifestyle.
Early humans were omnivores and crucially relied on plants for food, medicine, and psychoactive substances.
Modern-day hunter-gatherer societies, like the !Kung of central Africa, spend two days per week acquiring food, allowing for leisure time.

Shift to Agriculture

Settling in one place offered advantages: reliable food supply, access to trade routes, and consistent water sources.
This shift led to cultivation of plants, domestication of animals, and permanent settlements.
Resulted in increased food reliability, larger populations, greater environmental control, and specialization in roles.

Origins of Agriculture

Defined as tilling land for the deliberate planting of crops; provides year-round food supply.
Independent development of agriculture occurred in Asia Minor, China-Southeast Asia, and the Americas between 5,000-7,000 years ago.
Earliest agricultural indications found in arid regions such as the Fertile Crescent (modern Iraq, Iran, and Turkey).

Theories of Domestication Transition

Childe's Theory: Humans and herd animals congregated near watering holes, which led to soil disturbance and favoring of "weedy" grass species, initiating the Neolithic Revolution.
Sauer's Hypothesis: Sedentary living emerged in favorable climates, with less optimal areas being settled as populations grew, compelling plant domestication.
Anderson's Theory: Highlights the role of weeds in creating genetic variation in disturbed habitats, leading to domesticated plants.
Binford and Flannery's Hypothesis: Early gatherers became skilled botanists, leading to gradual cultivation necessity driven by population pressures.

Centers of Agricultural Origin

Asia Minor (Near East): Evidence from Jarmo indicates the cultivation of wheat and barley, along with domestication of goats, sheep, and various crops; urban civilization developed in Tigris-Euphrates valleys around 6,000 years ago.
Central China (Far East): Agriculture evidence from the Yang-Chao site shows developed rice agriculture and complex societies dating back roughly 6,000 years.
Central America: Agriculture emerged slower in Central America compared to Asia Minor, with key developments like the domestication of maize and other crops appearing around 7,500 years ago.

Agricultural Developments in Central America

Transition from hunter-gatherer lifestyles to agricultural practices was gradual, with a mix of cultivation and wild harvesting.
By 3,500 years ago, significant agricultural practices included the domestication of various crops like corn, tomatoes, and squash.
Advanced agricultural practices by 2,500 years ago showcased irrigation systems and selective crop cultivation by Aztec, Mayan, and Inca civilizations.

Selection Pressures on Plants

Plant characteristics evolve through the cumulative effects of the genome and natural selection.
Cultivation of wild plants leads to significant modification of their phenotypic traits.
Passive selection occurs when the link between planting and harvesting promotes beneficial cultivars, even without deliberate selection.
Wild plants produce many seeds that mature over time, leading to some seeds surviving unfavorable conditions.
Genotype 1: Seeds mature slowly, few at once; Genotype 2: Seeds mature simultaneously, resulting in higher harvest efficiency.
Characteristics favored in cereal crops include:
- Uniform seed maturation for consistent harvest.
- Compression of tillering to encourage synchronous seed maturity.
- Loss of seed appendages to prevent shattering before harvest.
- Simultaneous germination by removing chemical inhibitors.
- Increase in number of florets for more seed production.
- Reduction of day-length sensitivity for adaptability to varied climates.
- Loss of shattering to retain seeds on the plant until harvest.
- Increased starch reserves in seeds to enhance seedling competition and growth.
Weedy species adapt by synchronizing seed maturity with crop plants, complicating harvesting.

Geographic Origin and Spread of Plants

Many common food plants had restricted original distributions; introductions transformed agriculture and diets.
Notable introductions include:
- Potatoes from South America to Europe.
- Tomatoes and chili peppers from South America to other regions.
Romans brought Mediterranean species to Northern Europe, while Arabic colonization introduced rice and citrus.
European colonization significantly reshaped crop distributions, such as corn and potatoes spreading across Europe.
Asia boasts many indigenous crops, particularly rice; significant American introductions include corn and chili pepper.
Africa's indigenous food plants include coffee and millet, with important introductions from Asia and the Americas.
The Americas are rich in native crops such as maize and potatoes, with few crops originating in North America.

The Green Revolution

Focus on high-yield crops has led to trade-offs in disease and pest resistance.
These crops generally require intensive resources: fertilizers, water, and pesticides.
The Green Revolution often benefits wealthy nations and large-scale farms while disadvantaging developing regions.
Monocultures increase vulnerability to pests and diseases, exemplified by the Irish potato famine due to reliance on a single crop variety.
The cycle of breeding for yield often results in pests adapting and necessitating new resistant cultivars.

Plant Breeding: Genetic Modification

Plant breeding methods include genetic crossing, back-crossing, artificial doubling of chromosome numbers, and genetic mutation.
Genetic crossing maintains hybrid vigor in crops, with cloning methods like grafting and tissue culture facilitating propagation.
Triticale, a hybrid of wheat and rye, offers higher resilience and yields, developed in the 1960s.
Colchicine is used to induce polyploidy in plants, resulting in increased size and robustness—prevalent in many modern crops.
Genetic mutations can promote beneficial traits; Brussels sprouts are a notable example of a successful spontaneous mutation.
Genetic engineering introduces genetic information from other organisms to enhance crop traits; common crops include genetically engineered canola and corn.
Strong consumer resistance to GE crops in Europe has led to regulatory challenges, and concerns persist about ecological impacts and accessibility for farmers in developing nations.

Genetic Diversity

A diverse genetic pool is crucial for developing new crop varieties and medications.
Loss of older plant varieties limits available genetic resources beneficial for breeding programs.
Geneticists are seeking old cultivars, such as apples, to inform new variety development.
Tropical rainforests house a significant portion of Earth's species and genetic resources, with many plants yet to be discovered that could offer essential food or medicinal benefits.

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Description

This quiz explores the botanical classification, history, and utilization of Teff, a vital food plant. Participants will answer questions regarding its family, types, native distribution, and processing methods. Dive deep into the significance of this important crop and its role in agriculture.