Other bacteria do the reverse and return nitrogen to its gaseous form. In this game, youth will play the role of nitrogen atoms traveling through the nitrogen cycle. They will gain an understanding of the varied pathways through the cycle and the relevance of nitrogen to living things.
Seaweed picks up nitrogen in a process called nutrient bio-extraction. Many plants and animals cannot survive when there is too much nitrogen in the water, but seaweed takes in the nitrogen. Nitrogen: An important element of the periodic table. It does not have a color or an odor. Nitrogen is essential for growth and reproduction of all living things. The waters of New England are home to abundant and diverse kelp forests, where large species of kelp provide habitat for countless marine organisms.
The Atlantic Wolffish is an important resident of the kelp beds. They prey upon Sea Urchins that graze upon the kelp. Wolffish protect kelp from predation and allow kelp forests to flourish, which is good news for that fragile marine ecosystem. The loss of a predator, such as the Atlantic Wolffish, would result in an increase of herbivores urchins, in this case , which leads to a decrease in the abundance of kelp that provides habitat for many species in New England waters.
Protecting important predators will build resilience for our ecosystems in more ways than we can count. For more information on kelp and climate, visit the Protecting Special Places page Conservation Law Foundation website. Seaweed farming, a type of aquaculture, is the practice of cultivating and harvesting seaweed.
Farmers grow high quality and abundant food, while also improving the environment. Since seaweed is a great source of food, fuel, and environmental remediation, it is important that we continue to innovate new and exciting ways to cultivate these species. This activity is designed to be done in a longer session. If extended time is not available, you may consider delivering Part 1 and Part 2 into two activity sessions. Aquaculture: The cultivation of aquatic organisms such as fish, shellfish, sea vegetables, etc.
Seaweeds are an important marine resource that humans use for wrapping sushi, for thickening ice cream, and for adding to cosmetics, pharmaceuticals, and animal feed. Seaweed is also important to us because it serves as habitat for other sea life that we depend on. Even though most of the global seaweed production is farmed, there is still a large industry based on wild harvesting.
In Maine, there is a large rockweed industry that supplies seaweed for fertilizer and livestock feed by harvesting it from the rocky shore. Sustainability refers to our ability to preserve the number of resources. The sustainability of a fishery like this one depends both on the area being harvested, and on how much seaweed is being taken.
In this game, youth will have an opportunity to demonstrate their response as consumers of a resource in this case, rockweed. The rocky shore represents the area of potential harvest, and the rockweed represents the resource the consumers want to use. Sustainable: able to be used without being completely used up or destroyed.
Fishery: the occupation or industry of taking fish or other animals such as shellfish or seaweed from the sea. Carrying capacity: the maximum population that an area will support without deteriorating. With all their newfound knowledge about seaweed aquaculture, participants might be wondering how to stay involved with seaweed.
There are many ways to turn a love of seaweed into a career! They will also have an opportunity to review the information they may have learned throughout this toolkit. Career: a job or profession that someone does for a long time. RULES: This game is similar to charades, where one player from each team will try to get their team to guess the person on their card. However, each round will have a different set of rules and each person will only have one minute to act out as many cards as possible.
There are three rounds in total, and each team gets a point for each career that they guess correctly. The team with the most points at the end of all three rounds wins the game.
Adaptation: Some groups may benefit from exploring careers prior to Round 1. As a group, or in small groups, talk about careers and what each career might involve. Have participants work in partners to act out careers together, so they are familiar with the careers prior to guessing. There is nobody gesturing, facial clues, or other sounds allowed.
Players can only mimic or give gestures to provide clues like charades. An example for the Mickey Mouse card is: the player might gesture big ears on top of their head to represent Mickey Mouse ears. Calendar Give News Find us Contact. Cooperative Extension: 4-H. The University of Maine offers over academic majors! Identify the different parts of a seaweed. Other popular edible seaweeds include wakame and kelp -- or kombu -- which are both brown seaweed varieties harvested and marketed in Japan and elsewhere.
Seaweeds are good sources of potassium, iodine, vitamins and other trace elements. Vegetable gelatin from certain red seaweed species -- called agar -- offers an important medium for culturing bacteria and fungi for medical purposes.
Seaweeds are a complex group of organisms, and they can reproduce in a number of ways. Some reproduce asexually, while more advanced seaweeds might release zoospores that swim off and anchor themselves to a distant rock and begin growing. Other advanced types of seaweed reproduce sexually by forming sex cells -- gametes -- that have to fuse before growth can begin.
These seaweeds secrete sex pheromones to attract gametes, much as higher organisms do. Seaweeds are adept at reproduction, and many species are invasive. Sargassum muticum, or wireweed, is especially prolific outside its natural habitat off the coast of Japan. In Irish waters, it creates an obstruction for swimmers and boaters and blocks light to other organisms. Chris Deziel holds a Bachelor's degree in physics and a Master's degree in Humanities, He has taught science, math and English at the university level, both in his native Canada and in Japan.
He began writing online in , offering information in scientific, cultural and practical topics. All offspring resulting from asexual reproduction are clones; they are genetically identical to each other and the parent seaweed. Carrageean products. Agar plates. Seaweeds area food source for humans especially in East Asia, it is most commonly associated with Japanese food. Seaweeds also are used to make a number of food additives such as alginates and carrageenan which is used in cooking and baking as a vegetarian alternative to gelatine.
Many seaweeds are used as medicine. Alginates are used in wound dressings and in the production of dental moulds and agar is used very widely in Microbiology to help grow bacterial cultures. Seaweeds are ingredients in toothpaste, cosmetics and paints and are used in industrial products such as paper coatings, adhesives, dyes, gels, explosives and many more.
Much of the oil and natural gas we use today formed from seaweeds which partially decomposed on the sea floor many millions of years ago. Japanese food uses seaweeds extensively - Kombu a brown alga and Kim nori a red alga. Join Scripps' Institution's Russell Chapman as he discusses the important roles algae have played in the development of life as we know it.
Thanks to I would sincerely like to thank the many members of the Flickr community who have given me permission to use their wonderful images for this unit. Their contributions really make this unit come alive!
Next: Brown Algae Marine Algae Seaweed is a term applied to multicellular, marine algae which are large enough to be seen by the eye unaided.
Some can grow to up to 60 metres in length. In Saccharina japonica blue light promoted sporogenesis while red light inhibited sporangium formation Mizuta et al. Bogaert et al. Also the process of gamete release has been shown to be wavelength-specific. Blue light has been shown to induce gamete release in both Fucus and Dictyota Kumke , Pearson et al. Despite these clear indications that light quality specifically induces or inhibits reproduction and growth, the quest for the underlying photoreceptors and signalling pathways has proved a hard nut to crack Hegemann Phytochrome seems to be present only in streptophyte algae, some early diverging prasinophytes and stramenopiles, but not in red algae Falciatore and Bowler , Duanmu et al.
Nevertheless, algae contain a rich set of photoreceptors Hegemann Instead of phytochrome, stramenopiles possess their own blue light photoreceptor, aureochrome Takahashi et al.
The transcriptome of Saccharina japonica sporophytes under blue light was characterized by Deng et al. The results indicated that the number of differentially expressed genes was significantly higher under red light conditions compared to blue light. However, the aureochrome and cryptochrome photoreceptor genes showed no significant differential expression among the different light qualities.
These results are promising but also indicate that our understanding of the molecular mechanism of non-photosynthetic light perception and its control on a circadian clock is still limited, especially in comparison with Chlamydomonas see Mittag et al.
Given the importance for seaweeds to sense their environment, either through photoperiod or temperature, one should realize that these characteristics change across latitudinal gradients. So far, relatively little attention has been paid to measuring and understanding ecotypic latitudinal variation among strains. Most studies addressing intraspecific variation have concentrated on the effects of temperature regimes on growth and survival, and their biogeographic implications e.
However, the growing demand for seaweed in mariculture increases the need to better understand the degree of adaptation among latitudinal ecotypes and the limits of acclimation. So far studies are limited. Efforts to combine quantitative genetics and breeding with genomic information in commercial seaweeds are leading to the identification of quantitative trait loci e.
Liu et al. The diversity of life cycles in seaweeds is reflected in the wide variation of processes that control life cycle progression.
A huge amount of research, mainly in the second half of the 20th century, has uncovered the critical roles of temperature, photoperiod, irradiance and, in some cases, nutrients as factors controlling reproduction in many species. There was a bias toward brown and red algae, with fewer studies addressing fertility in green seaweeds. This ecological and ecophysiological information forms an excellent basis for future studies that address reproduction and life cycle progression at a molecular level.
The growing demand for seaweed resources, either as feed, food or biomass, creates a need for sustainable seaweed exploitation. This societal demand presents a direct incentive to alleviate a number of major bottlenecks which currently impede mariculture practices Charrier et al.
An excellent knowledge of seaweed life cycles, including better control of the different developmental stages, which allows handling of seaweed in an aquaculture setting, is imperative. In contrast with the large number of ecophysiological studies to date, our knowledge of the underlying molecular basis of cell growth, development and reproduction falls short.
For example, despite clear indications that photoperiod plays an important role in controlling reproduction, circadian clock genes have hardly been characterized from seaweeds, which is in contrast to the extensive knowledge on clocks in some unicellular algae e.
Chlamydomonas , Ostreoccocus : see Mittag et al. In flowering plants, circadian clock genes control flower development, among other processes. Most genes have been characterized from genetic screening for mutants with altered flowering timing, or with defects in the circadian expression of reporter genes Corellou et al.
A similar approach, applied to seaweeds and drawing on the extensive existing ecophysiological data, has the potential to significantly increase our knowledge of seaweed reproduction. At present, considerable progress is being made by establishing a number of model organisms for which whole genome data are already available or are in the process of being generated, including Ectocarpus Cock et al.
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