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Based on your observations, you suggest that the presence of water could be accelerate the growth of bread mold. This is?
what is the benefit of publishing in the journal?
The quality of the report will meet high scientific standards.
which of the following is a question that can be answered by science?
How does DNA influence a persons health?
How do you determind the independent variable in an experiment?
It is the one thing that the experimenter changes.
How do you identify the dependent variable in an experiment?
It is the measurable result of the independent variable.
which of the following characteristics of living things best expains why some north american birds fly south for the winter?
Living things respond to their environment.
The process by which organisms keep everything inside their bodies within certain limits is called?
Using a universal system of measurement is MOST important during which part of scientific methology?
Scientist will never know why dinosaurs became extinct. Therefore, scientist should
continue to learn as much as they can about dinosaur extinction.
Suppose that a scientist proposes a hypothesis about how a newly discovered virus affects humans. Other virus researchers would likely
design new experiments to test the proposed hypothesis.
How do scientific theories compare to hypotheses?
Theories unify a broad range of observations and hypotheses
Which of the following characteristics of living things best explains why dogs pant or sweat through their paws when hot?
Living things maintian internal balance
Would a scientist who studies evolution also have to learn about other branches of biology? why or why not?
Yes; the different branches of biology are interrelated.
Which of the following should a scientist do to make it easier for others to replicate his experiment?
Use the meteric system when communicating procedures and results.
water molecules are polar with the
oxygen side being slightly negative and the hydrogen being slightly positive.
why is carbon so special compared to other elements?
carbon can bond to one another and form a lot of different structures.
The branch of biology dealing with interactions amoung organisms and between organisms and their environment is called
which of the following descripitions about the organization of an ecosystem is correct?
species make up populations, which make up communities
the lowest level of environmental complexity that includes living and noniving factors is the
What is an ecological model of the relationships that form a netwrok of complex interactions amoung organisms in a community from producers to decomoposers?
what is the term for each step in the transfer of energy and matter with in a food web?
A bird stalks, kills, and eats the insect. which pair of ecological terms describes the bird?
Of the remaining energy, some is used for the organisms life process, and the rest is
eliminated as heat.
Which is a biotic factor that affects the size of a population in a specific ecosystem?
number and kinds of predators in the ecosystem.
Matter can recycle throught the biosphere because
biological systems do not use up matter but they tranform it.
the repeated movement of water between Earth's surface and the atmosphere is called?
the water cycle
organisms need nutrients through living systems are different because
energy flows in one direction, and nutrients recycle
phosphorus is very important for living things because living ogranisms need phosphorus for
DNA and RNA
why cant the producers in some ecosystems make an unlimited supply of organic material?
One or more nutrients are in short supply.
The average conditions of the atmoshpere in a particular area are reffered to as the area's?
How does an area's weather differ from the area's climate?
Weather is the areas day to day conditions and climate is the areas average conditions.
Earth has three main climate zones because of the differences in latitude and, thus,
distribution of sunlight.
An organisms niche is
the range of physical and biological conditions in which an organism lives and the way it obtains what it needs to surviv and reproduce
No two species can occupy the same habitat at the same time
because of the competitive exclusion principle.
how is parasitism different from commensalism?
one organism is harmed in parasitism and no organisms are harmed in commensalism.
what is one difference between primary and secondary succession?
secondary succession begins on soil and primary succession begins on newly exposed surfaces.
which of the following occurs during the ecological succession of an ecosystem?
living organisms modify their environment a little at a time.
which animal would be found in the biome that has cold to moderate winter, warm summers, and fertile soils, and is home to a variety of vegetation, such as coniferous trees, broadleaf decidous trees, flowering, shrubs, and ferns?
If a population grows larger than the carrying capacity of the environment, the
death rate may rise.
which would be least likely to be affected by a density dependent limiting factor?
a small, scattered population
demographic transition is change from high birth rates and high death rates to?
low birth rates and low death rates.
countries in the first stage of demographic transition have?
a high death rate and a high birth rate
The various growth phases through which most populations go are represented on?
a logistic growth curve
Sea otters live in the ocean. which of the following is NOT likely to be a limiting factor on the sea otter population?
A disease resulting in the deaths of one third of a dense popultion of bats in a cave would be a?
density dependent factor
what is one negative consequence of the Industrial revolution?
environmental harm from the burning of fossil fuels.
when farming, overgrazing, climate change, and/or seasonal drought change farmland that cannot support plant life, it is called?
An example of sustainable resource use is the use of predators and parasites to?
control pest insects
One property that makes DDT hazardous over the long run is that DDT is?
subject to biological magnification
Raising cattle and farming rice contribute to air pollution by?
releasing the greenhouse gas methane into the atmoshpere.
Corn planted in a field that has been previously planted with legumes and then plowed under is likely to be
more productive because bacteria living on the roots of legumes fix nitrogen in the soil.
How are phase 1 and phase 2 of logistic growth similar?
A population is increasing, moving toward its carrying capacity during both phases.
water lilies do not grow in desert sand because water availabilty to these plants in a desert is
a limiting factor
During a long period when there is no rainfall, a mountain lion may temperarily leave its usual hunting terrirtory to drink from a farm pond. This behavior is due to?
the change in an abiotic factor in its environment
which is an example of how biotic abiotic factors interact?
Tree roots split apart rocks in the ground
A tropical rain forest may not return to its original climax community after which of the following disturbances?
clearing and farming
which factor might not contribute to an exponential growth rate in a given population?
when calculating a populations ecological footprint, one has to take into account the
resources needed to clean up the populations waste
The work of schleiden and schwann can be summarized by saying that
all plants and animals are made of cells.
Electron microscopes can reveal details
1000 times smaller than those visible in light miscroscopes.
which type of microscope can produce three dimensional images of a cells surface?
scanning electron microscope
looking at a cell under a microscope you note that it is a prokaryote. how do you know?
the cell lacks a nucleus
which of the following statements about the nucleus is NOT true?
The nucleus is the site of protein assembly
which organelle converts the chemical energy stored in food into compounds that are more convenient for the cell to use?
which of the following is a function of the cell membrane?
regulates the movement of materials into and out of the cell
the cell membrane contains channels and pumps that helps move materials from one side to the other. what are these channels and pumps made of?
During diffusion, when the concentration of molecules on both sides of a membrane is the same, the molecules will
continue to move across the membrane in both directions.
An animal cell that is surrounded by fresh water will burst because the osmotic pressure causes
water to move into the cell
which list represents the levels of organization in a multicellular organism from the simplest level to the most complex level?
cell, tissue, organ, organ system
which term descibes the relatively constant internal physical conditions of an organism?
T or F? A scientist working in the early 1900s came up with a hypothesis. Over the next 100 years, other scientist test the hypothesis and found out that it could make predictions about numerous new situations time and time again. This hypothesis can now reightfully be considered a RESULT.
Charles Darwins ideas about change over time have been well tested by other scientist and is now considered to be a (________)
The combination of chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes is called (________________)
How would you determind whether something is living ot nonliving? (list of 8 things)
1. Made up of cells
3. Have DNA and RNA
4. Growth and development
5. Use of energy and materials
6. Responde to the envirnoment
T or F? The smallest units in living things that are considered to be alive are ORGANISMS.
A water is polar because there is an uneven distribution of electrons between the oxygen and the (_________) atoms.
List the 6 most common elements found in living things:
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfure
explain how monomers become polymers and how polymers becom monomers.
monomers become polymers by dehydration synthesis, which is taking out the water to join the monomers to become polymers. Polymers become monomers by hydrolysis, which adds water that breaks down the polymers into monomers.
T or F? ADHESION is responsible for the surface of the water in a graduated cylinder that is slightly curved at the sides.
T or F? The substances that are present when a chemical reaction begins are the PRODUCTS.
T or F? Proteins that speed up the rate of reactions in living things are SUBSTANCES.
To ro F? An ecologist who is studying a group of ecosystems that have similar climates and are home to similar organisms is studying a COMMUNITY.
T or F? Only 10 percent of the ENERGY in a trophic level is available to organisms at the next trophic level.
Explain how energy moves into, moves through, and moves out of an ecosystem.
Energy starts out at the sun then the autotroph consumes the energy by photosynthesis. Heterotrophs then consumes the energy from the autotroph by eating and digestion. The energy that is passed on only 10 percent of that energy is consumed the rest is used for growth or given off as heat.
T or F? scientists classify the nitrogen, carbon. phosphorus, and water cycles as BIOGEOCHEMICAL CYCLES.
T or F? The burning of fossil fuels and photosynthesis are part of the PHOSPHORUS cycle.
T or F? Aquatic ecosystems can recieve a large input of a LIMITING NUTRIENT from the runoff from heavily fertilized fields.
living organisms require nitrogen to make nitrogen containing compunds, such as (_________) and nucleic acids.
Human activities such as mining and the production and application of fertilizer are part of the (________) cycle.
Compare the movement of energy in the biosphere whith the movenment of metter through the biosphere.
Energy moves throught the biosphere in one direction and some of the energy is lost as it moves through the trophic levels. Matter moves in all different direction and is never either created or destroyed just tranformed.
Describe the roles of bacteria in the nitrogen cycle.
we depend on bacteia in soil to convert nitrogen gas into nitrogen coompunds so it can be used and absorbed by plants by the process of nitrogen fixation. Then when there is too much nitrogen compounds in the soil, bacteria converts nitrates into nitrogen gas and releases it into the atmosphere by the process of denitrifacation.
T or F? An ecologist who is studying a group of ecosystems that have similar climates and are home to simiar organisms is studying a COMMUNITY.
T or F? OXYGEN is important for ecosystems because it is used by plants during photosynthesis.
False; carbon dioxide
some orchids grow high on trees so that they can get enough light for photosynthesis. The trees are unaffected by the presences of the orchids. The relationship between the orchids and the trees is an example of (________________)
Regrowth of grasses, ferns, wildflowers, and saplings after a forest fire is an example of (________) succesion
A whale fall community begins when the body of a dead whale falls to the bottom of the ocean. Expain why plants do not participate in the succesion of a whale fall community as they do in land ecosytem succesion.
plants do not participate because the whale falls to the bottom of the ocean where there is no light so plants don't grow.
T or F? If the death rate of a population is greater than the birth rate, the population DECREASES.
T or F? when you graph a populations exponential growth over time you will have an S-SHAPED graphh.
false; J shaped
T or F? The EXPONENTIAL model of popuation growth accounts for theinfluence of carrying compacity.
T or F? Denstity DEPENDENT limiting factors affect all populations whether the population size is two or two hundred.
In an entire wolf population dies, the moose population on which it preys will grow to the enviroments (_________)
How can a demographer predict how a population will change in the future?
The demographer creates an age structure graph and also looks at the limiting factors the population has.
Compare and contrast the graph of exponential growth to the graph of logistic growth.
Exponential growth is shown on a graph as J shaped because exponential growth means that the population has unlimited resources and so the population will keep increasing. Logistic growth is presented on a graph as a S-shaped because logisic growth means the population has limited resources which means it will have a carrying compacity.
T or F? Ecologists studying the thinning of the Ozone layer determind that the main cause of the problem is GLOBAL WARMING
T or F? CARBON DIOXIDE is helpful when it is high in the atmosphere but is harmful to human health when it is close enough to the ground for people to breath.
T or F? BIODIVERSITY is important to humankind because we are part of it and are dependent up on it for our own survival.
T or F? Acid rain, dissolved carbon dioxide in ocean, and the thinning of bird eggshells due to DDT are all examples of POLLUTION threatening biodiversity
A location that has 170 species of birds likely has greater(______________) than a location that has 100 species of birds.
T or F? A SCANNING ELECTRON microscope allows light to pass through a specimen and focuses it using two lenses to form an image.
T or F? the assembly of ribosomes begins in a small dense structure called the CHROMATIN.
T or F? Cilia and flagellla are made of protien filaments called ENDOPLASMIC RETICULUM.
T or F? Ribosomes that synthesize proteins are found on the SMOOTH endoplasmic reticulum.
T or F? Moving materials from an area of low concentration to an area of high concentration requires ACTIVE transport.
T or F? a cell in a MULTICELLULAR organism must be able to carry out all the fucnctions neessary for life in order for the organism to survive.
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