Seed Dispersal Strategies

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Questions and Answers

Explain how Liebig's Law of Minimum applies to individual organisms.

Individual organisms can only grow to their maximum potential until they deplete a vital resource, despite having other resources in surplus.

Discuss the implications of limiting resources on population growth.

Population growth is restricted by the availability of vital resources, as populations can only expand until the most limiting resource is exhausted.

What is indeterminate growth and provide an example?

Indeterminate growth refers to organisms that do not have a maximum size limit, such as goldfish, which can continue to grow under certain conditions.

How do plants obtain nitrogen in nutrient-deficient environments like Mount St. Helens?

Plants obtain nitrogen through their roots, particularly from trace amounts found in the MSH tephra. Signup and view all the answers

List at least two reasons why organisms need nitrogen.

Organisms need nitrogen to create proteins and nucleic acids, such as DNA and RNA, which are essential for various cellular functions. Signup and view all the answers

What are the main components of a seed and their future roles?

The main components are the seed coat (protection), plumule (shoot), hypocotyl (stem), radicle (root), and cotyledon (food storage). Signup and view all the answers

How do large cotyledons benefit seed survival and growth?

Large cotyledons store more energy, allowing seeds to last longer before germination and to grow quickly to overtop competitors. Signup and view all the answers

What are the pros and cons of seeds with small cotyledons?

Seeds with small cotyledons can produce many more seeds and enable longer distance dispersal, but each seed has a lower chance of survival. Signup and view all the answers

What factors influence seed dispersal distance?

Seed weight and size influence dispersal distance, with lighter and smaller seeds typically traveling further. Signup and view all the answers

Explain the concept of evolutionary trade-offs in relation to seed characteristics.

Evolutionary trade-offs refer to the allocation of energy towards traits that enhance dispersal or survival, where improving one trait often reduces the efficiency of another. Signup and view all the answers

What does seed fitness refer to in the context of plant reproduction?

Seed fitness refers to the number of offspring that survive to reproduce and how much an individual contributes to the next generation. Signup and view all the answers

How does the seed coat evolve to cater to environmental challenges?

The seed coat evolves in thickness and properties to protect seeds from environmental threats such as crushing, digestion, and moisture loss. Signup and view all the answers

What triggers germination in seeds, and what occurs during this process?

Germination is triggered by favorable conditions such as moisture and temperature, leading to the seed's emergence and the growth of the radicle into the root system. Signup and view all the answers

What are the three structural nutrients that plants obtain, and where do they come from?

The three structural nutrients are Carbon (from air), Hydrogen (from water through roots), and Oxygen (from air and soil). Signup and view all the answers

What do the NPK numbers on fertilizer indicate?

The NPK numbers indicate the proportions of Nitrogen, Phosphorous, and Potassium in the fertilizer. They help match the fertilizer to the specific needs of the plants. Signup and view all the answers

Why are lupines significant in the recovery of Mount St. Helens?

Lupines were the first plants to establish in the pumice plains after the eruption, helping to stabilize the soil. They are able to survive in the harsh volcanic ash conditions. Signup and view all the answers

How does nitrogen contribute to plant growth?

Nitrogen is essential for the production of DNA and proteins, including enzymes crucial for plant metabolism. It promotes healthy green foliage. Signup and view all the answers

Explain the role of phosphorus in plants.

Phosphorus is crucial for the formation of the phosphate backbone in DNA and is important for root development and flowering. It enhances energy transfer within the plant. Signup and view all the answers

What might happen to plants if they do not receive essential nutrients?

Plants may exhibit poor growth, yellowing leaves, stunted development, or may not produce flowers or fruits. Severe deficiencies can lead to plant death. Signup and view all the answers

Identify one macronutrient and one micronutrient essential for plant health and their roles.

Macronutrient: Nitrogen (for green foliage and DNA), Micronutrient: Magnesium (for chlorophyll production and sunlight absorption). Signup and view all the answers

What roles do macronutrients and micronutrients play in plant development?

Macronutrients are needed in large quantities for structural components and metabolic functions, whereas micronutrients are required in small amounts for various catalytic and structural roles in plants. Signup and view all the answers

What characterizes dynamic equilibrium in forest ecosystems?

Dynamic equilibrium is characterized by a constant state of change and flux within an ecosystem due to disturbances and succession over long periods. Signup and view all the answers

How does biodiversity affect ecosystem stability?

Higher biodiversity increases ecosystem stability by enhancing resistance to disturbances and resilience in recovery. Signup and view all the answers

Identify two reasons why biodiversity is important beyond biological reasons.

Biodiversity is vital for providing ecosystem services such as carbon sequestration and for tourism, which can have economic benefits. Signup and view all the answers

Explain the significance of ecosystem complexity in relation to biodiversity.

Increased ecosystem complexity leads to greater biodiversity, as it can support a wider range of organisms and interactions. Signup and view all the answers

What happens to ecosystems when biodiversity is lost?

Loss of biodiversity decreases ecosystem stability, lowers complexity, and reduces the overall capacity to support diverse organisms. Signup and view all the answers

Describe the impact of forest gaps on biodiversity.

When forest gaps open, there is competition among organisms to occupy the space, which can lead to changes in biodiversity dynamics. Signup and view all the answers

What is the difference between resistance and resilience in an ecosystem?

Resistance refers to an ecosystem's ability to withstand disturbances, while resilience is its ability to recover quickly after such events. Signup and view all the answers

Why do some ecosystems exhibit greater biodiversity compared to others?

Greater biodiversity in some ecosystems is often due to factors such as the ecosystem's age, complexity, and time available for succession. Signup and view all the answers

What is the primary structure of a protein and how is it formed?

The primary structure of a protein is the linear sequence of amino acids that forms the polypeptide chain, created by peptide bonds between the amino group of one amino acid and the carboxyl group of another. Signup and view all the answers

Describe the role of hydrogen bonds in secondary protein structures.

Hydrogen bonds stabilize the secondary structure of proteins, forming structures such as alpha helices and beta sheets, without involving R groups. Signup and view all the answers

How does a single DNA mutation affect a protein's structure and function?

A DNA mutation can alter the amino acid sequence in the primary structure, leading to changes in the protein's shape and, consequently, its function. Signup and view all the answers

What distinguishes ionic bonds from covalent bonds?

Ionic bonds involve the transfer of electrons between atoms resulting in charged ions, whereas covalent bonds involve the sharing of electrons between atoms. Signup and view all the answers

Explain how the tertiary structure of a protein is determined.

The tertiary structure of a protein is determined by the interactions of R groups, including ionic bonds, hydrogen bonds, and disulfide bridges, which dictate the protein's specific 3D shape. Signup and view all the answers

What is meant by the term 'quaternary structure' in proteins?

Quaternary structure refers to the assembly of multiple polypeptide chains into a single functional protein complex. Signup and view all the answers

What factors can denature a protein?

A protein can be denatured by extreme temperatures or changes in pH, causing it to lose its shape and function. Signup and view all the answers

How do intermolecular forces differ from intramolecular forces?

Intramolecular forces are the forces that hold atoms within a molecule together, such as ionic and covalent bonds, while intermolecular forces are attractions between different molecules. Signup and view all the answers

What are the characteristics of polar bonds compared to non-polar bonds?

Polar bonds have an unequal distribution of electron density, leading to partial charges, whereas non-polar bonds have an even distribution of shared electrons and do not have partial charges. Signup and view all the answers

What type of bond is responsible for the stability of disulfide bridges?

Disulfide bridges are stabilized by covalent bonds formed between the sulfur atoms of two cysteine residues. Signup and view all the answers

Study Notes

Seed Dispersal and Plant Survival

Plants utilize various seed dispersal strategies: wind, animal-fruited seeds, ballistic/gravity dispersal, and sticky seeds.
Seed characteristics affecting dispersal distance include weight and size.
Anatomy of a seed includes:
- Seed coat: protective outer layer, variable thickness for energy conservation.
- Plumule: develops into the shoot.
- Hypocotyl: develops into the stem.
- Radicle: develops into the root.
- Cotyledon: serves as food storage, varies in size from large (acorns) to small (poppy seeds).

Advantages and Trade-offs of Cotyledon Size

Large cotyledons offer benefits like increased energy storage, prolonged survivability before sprouting, quicker growth to outcompete others, and higher individual seed survival rates.
Small cotyledons can produce more seeds, facilitating longer-distance dispersal, but each has a lower individual survival chance.
Evolution involves trade-offs where advantageous traits in one area may hinder survival or dispersal in another.

Nutritional Needs of Plants

Key structural nutrients: Carbon (from air), Hydrogen (from water via roots), and Oxygen (from air and soil).
Primary nutrients required from fertilizers include Nitrogen (for foliage), Phosphorus (for roots and blooms), and Potassium (for overall health).
Macronutrients (NPK) are essential in large quantities; micronutrients are required in smaller amounts.
Carbohydrates are crucial for building cellulose and energy metabolism.

Recovery of Mount St. Helens and Plant Success

Lupines were the first plants to naturally establish in Mount St. Helens, thriving in volcanic ash despite being poor dispersers.
Alternative plants like Fireweed reached the area quickly but did not survive due to their lesser adaptability to conditions.
Survivability of a species depends heavily on vital resource availability; resources can become limiting, restricting growth.

Proteins and Their Functions

Proteins are complex molecules made from amino acids, serving diverse functions such as muscle formation, enzyme activity, and neurotransmitter synthesis.
Proteins are synthesized in ribosomes through a process involving mRNA and translation.
Protein structures consist of primary (amino acid chains), secondary (coils or sheets), tertiary (3D shapes), and quaternary (complex assemblies).

Chemical Bonds and Molecular Structure

Intramolecular bonds (covalent, ionic) form “permanent” connections within molecules.
Intermolecular forces (IMFs) are transient electrostatic attractions between molecules.
Electronegativity determines bond types: covalent (0-0.4 EN difference), ionic (>1.7 EN difference).
Bond polarity arises from the uneven sharing of electrons, creating partial charges.

Biodiversity and Ecosystem Dynamics

Biodiversity refers to the variety of organisms within a habitat; greater ecosystem complexity correlates with higher biodiversity.
Ecosystems demonstrate dynamic equilibrium, characterized by continuous change and development through disturbance and succession.
Resistance and resilience are critical; ecosystems with higher biodiversity display greater stability against disturbances.

Importance of Biodiversity

Biodiversity is essential for food production, ecosystem services, and emotional connections to nature.
Loss of biodiversity diminishes stability and ecosystem complexity, creating a cycle of decline.
Stable ecosystems are more resilient and capable of recovering from disturbances effectively.

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Description

This quiz covers the various seed dispersal strategies employed by plants and their advantages and disadvantages. From wind and animal-mediated dispersal to ballistic methods and sticky seeds, you'll explore how these strategies affect the long-distance migration of plants. Test your knowledge of what characteristics aid in effective seed dispersal.