Chapter 2 Review of Topics SNC 1W1 PDF

Chapter 2: Review of Topics SNC 1W1 Section 2.1 What are the different spheres of the earth? Why is each one important? How do they all relate to each other and the notion of the biosphere? Lithosphere: The solid outer layer of earth, made up of the crust and upper mantle. The word “litosphere” c...

Chapter 2: Review of Topics SNC 1W1 Section 2.1 What are the different spheres of the earth? Why is each one important? How do they all relate to each other and the notion of the biosphere? Lithosphere: The solid outer layer of earth, made up of the crust and upper mantle. The word “litosphere” comes from the words “litho” meaning rock and “sphere” meaning layer Atmosphere: The sphere of air that surrounds earth, regulating its temperature and protecting it from the sun's radiation. Hydrosphere: The sum of all earth's water including oceans, rivers, lakes, ice and streams Biosphere: The realm of all living things on earth. They all relate to each other because they need each other to survive. Section 2.2 What is an ecosystem? An ecosystem is all the living organisms that share a region and interact with each other and their nonliving environment An ecosystem is composed of both biotic and abiotic factors - what is the difference between the two and can you state examples of each. Biotic = living things, the remains of living things, their products or wastes associated with their activities, such as nests (or where they live) Abiotic = Nonliving, temperature, wind, water, air, minerals What is the relationship between organisms, populations, communities and finally ecosystems? Organism: an individual animal or plant or single-celled life form Population: All members of the same species that live in the area Community: All the different populations living in the same area Ecosystem: All the living organism in the area and their nonliving environment Are all ecosystems large in nature? They can be either large or small. Could be the size of a forest or a pond. We looked at coral reefs in class more closely - what are they? How are they under threat? Examined the biotic and abiotic factors with gizmos Coral reefs are made up of colonies of hundreds to thousands of tiny individual corals, called polyps. Coral reefs are facing multiple stresses such as pollution, overfishing, and, overall, the ongoing climate change―consequently raising sea water temperatures and causing coral bleaching worldwide. Are natural ecosystems sustainable? What does this even mean? Why should we care if they are sustainable or not? Yes, many of the natural ecosystems are self-sustainable. This means that if it is maintained by natural processes, a human presence or interaction with the natural environment can disturb it and break its sustainability. THe reason to care for sustainability is because our forests, rivers, oceans and soils provide us with the food we eat, the air we breathe, the water we irrigate our crops with. We also rely on them for numerous other goods and services we depend on for our health, happiness and prosperity. Think about what the movie The Lorax teaches us about ecosystems and our role in taking care of them. The Lorax meant that unless someone cares about a situation, nothing will improve. The Once-ler didn't care about harming the land, birds, water, and animals while cutting down the Truffula trees. And as a result, he cut them all down and destroyed the environment. Section 2.4 All organisms require energy to survive. What is the source of almost all of this energy? Radiant energy (light energy and ultraviolet energy) from the Sun is the source of almost all this energy How does this energy get converted into? About 70 % of radiant energy is absorbed by the hydrosphere and lithosphere and converted into thermal energy, warming Earth What is the process of photosynthesis? Can you describe it like a chemical reaction? What are the reactants and products? Recall we built molecular models of the reactants (carbon dioxide and water) and of the products (glucose and oxygen). Why is photosynthesis so important to our life? Photosynthesis is the process by which the Sun’s energy is converted to chemical energy After the process is complete, photosynthesis releases oxygen and produces carbohydrate molecules, most commonly glucose. These sugar molecules contain the energy that living things need to survive. A reactant is what you start with in a chemical reaction. Think of it like the “ingredients” A product is something you end up with, once the chemical reaction is done. Like a baked cake. What is the opposite reaction of photosynthesis called? Why is cellular respiration important? What are the reactants and products of this reaction? Where do the products come from? Cellular respiration is a complementary process to photosynthesis. This means the reactions are opposite to each other. Photosynthesis stores energy in sugars and cellular respiration releases the energy. It is important due to the fact that both processes need to occur in order to sustain life. Section 2.5 What are ecological niches and why are they important? Ecological Niche- the function a species serves in its ecosystem, including what it eats, what eats it, and how it behaves. Every species occupies a different niche. (though some may seem similar) There are different types of consumers - name them and give an example of each. Herbivore – eats only producers (i.e. plants) Carnivore – eats only consumers (i.e. animals) Omnivore –eats both producers and consumers Scavenger – eats dead remains (i.e. vultures) Decomposer – feeds on dead decaying organisms (i.e. fungi) What is a food chain? What is a food web? Can you identify these if given a food web; identify trophic levels and understand what this means? A food chain is a sequence of organisms, each feeding on the next, showing how energy is transferred from one organism to the next. A food web is a representation of feeding relationships within a community and gives us a better understanding of what really occurs in nature. To describe the position an organism has on the food chain we use the term trophic level which is the feeding level of the organism within a particular food chain What are ecological pyramids? What is biomass and how is this represented? Biologists use ecological pyramids to display relationships between trophic levels in ecosystems The three types of ecological pyramids are: Energy, Numbers, Biomass Biomass pyramids show the total mass of all organisms combined within that trophic level. Regardless of species populations are combined! Biomass is the TOTAL mass of all living organisms in a given area Section 2.6 All matter is cycled in nature. Water cycle, carbon cycle, nitrogen cycle - focus on carbon and nitrogen cycles only - Carbon cycle The carbon from the air enters the plants organism through photosynthesis, then after the plants absorb it, it enters the animals when they eat it, and once the animal dies off the carbon enters the ground after its decaying. - Nitrogen cycle After the plants eat or absorb the nitrogen into their system, it is passed from the producer to the consumer and up on the food chain. After these organisms die, the decomposers take in the nitrogen rich compounds and release them into the environment. Some bacteria convert into nitrogen gas and enter the atmosphere. How do human activities change/impact/influence the carbon cycle ? ***think of the article you researched as an example of this**** Burning fossil fuels, releasing chemicals into the atmosphere, reducing the amount of forest cover, and the rapid expansion of farming, development, and industrial activities are releasing carbon dioxide into the atmosphere and changing the balance of the climate system. Explain the importance of the nitrogen cycle and the role of decomposers. It's an essential ingredient that helps all living things on earth survive, because without it we might not survive. Understand that nitrogen is more difficult to obtain than carbon and water. Section 2.7 What determines the size of a population and where a species can live? Need to consider the influence of biotic and abiotic factors on whether a species will survive or not. Limiting factors = a factor that places an upper limit on the size of a population can be biotic, e.g. availability of food can be abiotic, e.g. access to water human activities often act as limiting factors in ecosystems Abiotic factors = can influence a species’ ability to survive Every species can survive within a range of these factors This is called the tolerance range Near the upper and lower limits, organisms experience stress This stress will reduce their growth, and health, and reproduction Tolerance Range vs. Optimal Range  - Biotic factors can also influence species survival. Know the types of species interactions on page 54. Competition: animals may compete for territory, water, food, or mates. Parasitism: where one organism, the parasite, benefits at the expense of another organism, the host. Commensalism: an association between two organisms in which one benefits and the other derives neither benefit nor harm Mutualism: association between organisms of two different species in which each benefits Predation: a biological interaction where one organism, the predator, kills and eats another organism, its prey ***think of the lab done in class where you were all birds with ‘different beaks’; you used different instruments to illustrate different beaks and had to compete against each other for food (sunflower seeds) *some species survived and some did not *** What is meant by the carrying capacity? Why is it important in terms of sustainability? Why are there limits on us fishing and hunting in terms of carrying capacity? Breakdown: MC and short answer questions ; bring a pencil and eraser