Algae/01/024 - Xtics & Importances Flashcards
- general xtics - importances -
Which of the following is not a condition necessary for sexual reproduction in algae?
a) Suitable pH
b) High salinity
c) Optimum temperature
d) Presence of appropriate light
B
Algae can have both unicellular and multicellular sex organs.
Algae possess sex organs that can be either unicellular or multicellular, depending on the species. This diversity allows for different reproductive strategies across various algae groups
Describe the role of secondary pigments in algae and provide examples of these pigments.
Secondary pigments in algae, such as carotenes, xanthophylls, and phycobilins, play a crucial role in capturing light energy for photosynthesis. These pigments absorb light wavelengths that chlorophyll cannot, thus broadening the range of light that algae can use for photosynthesis. For example, carotenes and xanthophylls absorb blue and green light, while phycobilins absorb red, orange, and yellow light, making them particularly useful in low-light aquatic environments
Discuss the significance of algae in aquatic ecosystems and their impact on environmental sustainability. Include examples of how algae contribute to or detract from ecosystem health.
- Sea weeds and other algae have been collected and use as food like Laminaria, Ulva, Chlorella
- Sea weeds are rech in iodine and have been used in the treatment of goitre.e.g Luminaria, Fucus
- Gracillaria in Asia are collected and used in agar.
- Many sea weeds are used as fodder as well.
- Red algae contribute to formation of coral reefs because of the formation of their calcareous exoskeleton.
- Diatomite is used in building high temperature furnaces because it is light in weight and fire proof.
- Diatomite from diatom cell walls is highly porous and is used as a filter for oils; most industrial filtration devices are made from diatomite.
- Many sea weeds are also rich in elemnts like Fe, Co, B, Cu, Zn, Co, Vn, Mo, Cr and are used in manufacture of organic fertilizers in European countries.
Negative
- Animal poisoning have been caused by blue green algae like Microcystis aeruginosa and Anabaena blooms forming .These blloms are toxic to the quatic environment and cause death to fishes and invertebrate organisms.
- When taken , toxic planktonic algae like Anabaena and Microcystis cause gastric problems, Gymnodinium brevis cause respiratory problems and Chlorella causes skin infection.
What is the primary basis for the classification of algae?
a) Habitat
b) Morphological and physiological features
c) Reproductive methods
d) Size and shape
b
Explain the process of isogamy in algae and how it differs from other forms of sexual reproduction.
Isogamy involves the fusion between motile gametes that are similar morphologically but different genetically. The gametes are called isgametes and the organisms are isogamous.
Anisogamy involves the fusion of motile gametes that are both morphologically(different in size) and genetically different. The male gamete is typically smaller than the female gamete.
Oogamy involves the fusion of a large, non-motile female gamete called the egg and a small, motile male gamete called the sperm.
All algae have eukaryotic cells.
No, blue-green algae are prokaryotic
membrane
Difference between eukaryotic and prokayotic?
Eukaryotic cells are complex cells contain a nucleus and other membrane bound organelles while prokaryotes are simple cells that lack a nucleus and other membrane-bound organelles
Evaluate the potential of algae as a sustainable resource for biofuel production. Discuss the benefits and challenges associated with this application.
Algae hold significant potential as a sustainable resource for biofuel production due to their unique characteristics and adaptability. Here’s an evaluation of the benefits and challenges associated with this application:
Benefits of Algae for Biofuel Production
-
High Productivity
- Algae can produce up to 10-100 times more oil per acre than traditional biofuel crops such as soybeans or corn. Their rapid growth rate enhances productivity.
-
Non-Competing Land Use
- Algae can be grown in non-arable land, including deserts and coastal areas, avoiding competition with food crops for agricultural land.
-
Efficient Resource Utilization
- Algae can grow in brackish water, seawater, or wastewater, reducing the need for fresh water. They can also utilize CO₂ from industrial emissions, contributing to carbon capture.
-
Diverse Products
- In addition to biofuels (biodiesel, bioethanol, and biojet fuel), algae can produce valuable co-products such as proteins, omega-3 fatty acids, and biofertilizers.
-
Environmental Benefits
- Algae-based biofuels are renewable and biodegradable, offering a lower carbon footprint compared to fossil fuels. Their cultivation can also mitigate nutrient pollution by absorbing nitrates and phosphates.
Challenges of Algae for Biofuel Production
-
High Production Costs
- Cultivating, harvesting, and processing algae into biofuel is expensive due to the need for specialized infrastructure and technology, including bioreactors or open pond systems.
-
Energy-Intensive Processes
- Algal biofuel production often involves energy-intensive steps such as dewatering, lipid extraction, and conversion to fuel, potentially offsetting environmental benefits.
-
Scaling Challenges
- Moving from laboratory or pilot-scale production to commercial-scale operations poses logistical and economic difficulties.
-
Risk of Contamination
- Open pond systems are susceptible to contamination by unwanted organisms, which can reduce productivity and increase maintenance costs.
-
Water and Nutrient Requirements
- Although algae can grow in non-freshwater systems, large-scale cultivation still requires substantial water and nutrients, which can strain resources if not managed sustainably.
-
Market Competition
- Algal biofuels must compete with cheaper fossil fuels and other renewable energy sources, which can hinder widespread adoption without supportive policies or subsidies.
Conclusion
Algae-based biofuels represent a promising sustainable energy resource, offering benefits such as high productivity, reduced competition with food crops, and environmental advantages. However, significant challenges, including high costs, energy-intensive processes, and scaling difficulties, must be addressed to realize their full potential. Advances in biotechnology, improved cultivation techniques, and supportive policies are essential to overcoming these barriers and making algal biofuels a viable alternative to fossil fuels.
Which type of algae has a cell wall composed of silica?
a) Green algae
b) Red algae
c) Diatoms
d) Brown algae
c
Describe the process of vegetative reproduction in algae.
1.By cell division
2.Fragmentation
3.Hormogone formation
4.Zoospores
5.Aplanospores
6.Akinetes
7.Adventitous thalli
8.Tubers
9.Bulbils
Analyze the role of algae in carbon sequestration and its potential impact on climate change mitigation.
Algae play a significant role in carbon sequestration, making them a promising natural solution for mitigating climate change. Their ability to absorb and store atmospheric carbon dioxide (CO₂) is central to this role. Here’s an analysis of their impact:
Role of Algae in Carbon Sequestration
-
Photosynthetic Efficiency
- Algae, like plants, use photosynthesis to convert CO₂ into organic carbon. Microalgae are especially efficient, with high growth rates and the ability to absorb large amounts of CO₂ relative to their biomass.
-
Carbon Storage in Biomass
- The organic carbon fixed by algae is stored in their cells. When algae are harvested and processed into products like biofuels, bioplastics, or biofertilizers, this carbon is retained in those materials, delaying its release back into the atmosphere.
-
Marine Algae and Ocean Carbon Pump
- Marine algae, particularly phytoplankton, form the base of the oceanic food web and contribute to the biological carbon pump. They absorb CO₂ and, upon death, sink to the ocean floor, effectively storing carbon for centuries or millennia.
-
Aquaculture and Carbon Recycling
- Algal aquaculture, such as seaweed farming, not only absorbs CO₂ but can also enhance carbon capture in coastal environments by sequestering carbon in sediments.
-
Synergy with Industrial CO₂ Sources
- Algae cultivation systems can be integrated with industrial facilities to capture CO₂ emissions directly from flue gases, reducing atmospheric release.
Potential Impacts on Climate Change Mitigation
-
Reduction of Atmospheric CO₂
- Large-scale algal cultivation can significantly lower atmospheric CO₂ levels. For instance, microalgae farms can act as “biological carbon scrubbers” when paired with power plants or other industrial emitters.
-
Sustainable Products
- Algae can produce biofuels, replacing fossil fuels, and bioplastics, reducing reliance on petroleum-based plastics. These applications lower carbon footprints and help transition to a low-carbon economy.
-
Ocean Health
- Algal growth in oceans contributes to carbon sequestration while enhancing biodiversity and mitigating ocean acidification caused by excess atmospheric CO₂.
-
Scalability
- Algal cultivation systems can be deployed in diverse environments, including degraded lands, saline water bodies, and urban settings, offering scalable solutions for carbon management.
Challenges and Limitations
-
Energy and Resource Requirements
- Cultivation, harvesting, and processing of algae require energy and nutrients. Inefficient systems can lead to a net positive carbon footprint.
-
Ecological Risks
- Unregulated algal blooms in natural water bodies can lead to eutrophication, negatively impacting aquatic ecosystems and reducing biodiversity.
-
Economic Viability
- High operational costs and competition with other carbon capture technologies may limit the widespread adoption of algal carbon sequestration projects.
-
Temporal Carbon Storage
- In some applications, the carbon sequestered by algae is released back into the atmosphere upon degradation, limiting long-term storage potential unless managed carefully.
Conclusion
Algae offer a versatile and efficient means of carbon sequestration with applications that align with climate change mitigation goals. They serve as a dual-purpose solution, addressing atmospheric CO₂ reduction while providing renewable resources. However, the full realization of their potential requires advances in cost-effective cultivation technologies, careful ecological management, and supportive policy frameworks to integrate algal systems into broader carbon management strategies.
What is the term for the plant body of algae that lacks differentiation into roots, stems, and leaves?
a) Thallus
b) Rhizoid
c) Frond
d) Blade
a
Explain the concept of alternation of generations in algae.
Alternation of generations in algae refers to the lifecycle pattern in which an organism alternates between two distinct multicellular stages: a haploid gametophyte and a diploid sporophyte. This process involves sexual and asexual reproduction, ensuring genetic diversity and adaptability in changing environments.
Key Stages of Alternation of Generations
-
Haploid Gametophyte Stage
- The gametophyte is a multicellular haploid stage (n) that produces gametes (sperm and eggs) through mitosis.
- Gametes are haploid and fuse during fertilization to form a diploid zygote.
-
Diploid Sporophyte Stage
- The zygote develops into a multicellular diploid sporophyte (2n) through mitotic divisions.
- The sporophyte produces haploid spores via meiosis, which can grow into new gametophytes, completing the cycle.
Types of Alternation of Generations
-
Isomorphic Alternation of Generations
- The gametophyte and sporophyte look similar and are morphologically indistinguishable.
- Example: Ulva (sea lettuce).
-
Heteromorphic Alternation of Generations
- The gametophyte and sporophyte differ in appearance, size, and function.
- Example: Laminaria (brown algae) has a large sporophyte and a microscopic gametophyte.
Process in Algae
-
Gametophyte Phase
- Gametophytes develop and produce haploid gametes through mitosis.
- Fertilization occurs when male and female gametes fuse, forming a zygote.
-
Sporophyte Phase
- The zygote undergoes mitosis, growing into a multicellular sporophyte.
- Sporophytes produce haploid spores by meiosis, which disperse and germinate into new gametophytes.
Significance of Alternation of Generations
-
Genetic Diversity
- The involvement of both meiosis and fertilization introduces genetic variation, enhancing adaptability.
-
Adaptation to Environment
- Alternating between haploid and diploid phases allows algae to exploit different environmental conditions.
-
Reproductive Success
- Producing large numbers of spores and gametes increases the chances of survival and reproduction.
-
Evolutionary Importance
- Alternation of generations represents a crucial evolutionary step in the transition from unicellular to complex multicellular organisms.
Conclusion
The concept of alternation of generations in algae demonstrates a balanced lifecycle that combines genetic variation through sexual reproduction and efficient population growth via asexual reproduction. This dual strategy has allowed algae to thrive in diverse and challenging environments, forming the foundation for many aquatic ecosystems.
Discuss the ecological and economic importance of algae in marine and freshwater environments. Provide examples of how algae are used in various industries.
