exam review answers

Pg .157

1) Mass=21.6g d=m/v d=21.6g/8.00cm3 d=2.7g/cm3

volume=8.00cm3

density=?

2) Mass=101g d=m/v d=101g/95.5cm3 d=1.06g/cm3

volume=95.5cm3

density= ?

3)mass=10.24g 10.24-2.42=7.82 d=m/v d=7.82g/5470cm3 d=0.00142g/cm3

mass of empty= 2.42g

volume=5470cm3

density=?

4) mass=0.92g d=m/v d=0.92g/2.12cm3 d=0.43g/cm3

volume=2.12cm3

density=?

5) No, this material will not float because its density is below 1.0g/cm3

Pg.175

10) mass=? M=dxv m=10.5g/cm3 x 10.0cm3 m=105g

volume=10.0cm3

density= 10.5g/cm3

17. a) density=? D=m/v d=35.7/5.01cm3 d=7.12g/cm3

mass=35.7 g

volume=5.01cm3

b) density=? D=m/v d=3.66/2.56cm3 d=1.42g/cm3

mass=3.66g

volume=2.56cm3

pg.260

7)mass=15g D=m/v d=15g/6.0cm3 d=2.5g/cm3

volume=6.0cm3

density=?

8)mass=? M=dxv m=7.87g/cm3 x 2.50cm3 m=19.67g

volume=2.50cm3

density=7.87g/cm3

Sustainable ecosystems review

Page 44 Questions 1-7 11, 14, 15.

1. The regions on earth where living organisms exist is called the biosphere.

2. Eutrophication is a process in which nutrient levels in aquatic ecosytems increase, leading to the increase in the population of primary producers.

3. An ecosystem includes all the interacting parts of a biological community and its environment.

4. The chemical reaction that changes solar energy into chemical energy is called photosynthesis.

5. A catagory of living things that is defined by how they gain energy is called a trophic level.

6. Cellular respiration is a process that derives energy from organic molecules in the precence of oxygen.

7. Warming of the earth caused by greenhouse gases trapping the energy that would otherwise leave the earth is called the greenhouse effect.

11. The organisms that are considered to be primary producers are organisms that are on the first trophic level. These organisms are plants such as grasses. Primary producers are so important to the biosphere because they preform the function of providing energy to the other organisms on the higer trophic levels by acting as food or the other organisms to consume.

14. The connection between fossil fuels and photosynthesis is that in a way, both these things create energy. When fossil fuels are burned it creates energy. When photosynthesis occurs energy is created from the sun into chemicals.

15.a) The Kyoto Protocal is an international agreement to reduce greenhouse gas emissions, which was signed by 180 countries. To meet the terms of the protocal, can reduce emissions or get credits for removing carbon dioxide from the atmosphere by planting trees in non-forest areas. since plants remove carbon dioxide in the atmosphere, large areas of trees and other plants, such as forests are known as carbon sinks.

b) countries can reduce the amount of carbon dioxide by creating more carbon sinks, which is the planting of many trees or the creation of forests.

Page 84 Questions 1-7

1. mutualism is a symbiotic relationship between two species in which both species benefit from the relationship.

2. A population is a group of organisms of one species that lives in the same place, at the same time, and can successfully reproduce.

3. Ecological niche is the biotic and abiotic pafactors that are nessasary for a species to survive.

4. the carrying capacity is the size of a population that can be supported indefinatly on the avaliable reasources and services of an ecosystem.

5. A parasite is an organism whose niche is dependent on a close assotiation with a larger host organism.

6. an ecological footprint is the measure of the impact of an individual or a population on the environment.

7. Connectivity is the links and relationships between ecosystems that are seperated geographically.

Page 122 Questions 7,8,10,16

7. The number and variety of organisms found within a specific region is biodiversity.

8. Maintaining biodiversity is so important because biodiversity boosts ecosystem productivity where each species, no matter how small, all have an important role to play.

10. A biodiversity hotspot is a place where there is an exceptionaly large number of species in a releatively small area. the most significant biodivesity hotspots are found in the tropics of south America, Africa, and Asia.

16. Deforestation is a threat to bidiversity because if you cut down trees and not replace them you are taking away a very important abiotic factor from the ecosystem. When you take away trees you are taking away a food source and a shelter from species, which will cause the ecosystem to become unsustainable.

Page 128 Questions 3,4

3. The size of a population that can be supported indefinitly by reasources and services of an ecosystem is known as its carrying capacity.

4. A hawk eats a fish that has eaten many smaller aquatic animals which had toxins in their bodies is an example of biomagnification.

the formula for photosynthesis is