Bio Questions EXAM
An inference is what?
A logical interpretation of an observation
What does a skeptical attitude mean in Science?
A skeptical attitude in science means a new idea will only be accepted if backed by evidence.
A scientific theory is what
A well tested explanation that unifies a broad range of observations
Cells use the energy available in food to make a final energy-rich compound called
ATP
Which of the following is used by cells to store and release the energy needed to power cellular processes
ATP
Heterotroph
An organism that cannot make its own food and gets food by consuming other living things for energy
How do autotrophs and heterotrophs differ in the way they obtain energy?
Autotrophs make their own energy, while heterotrophs get their energy from consuming foods, usually indirectly relating to autotrophs ( meat is from animals that eat grasses and such ).
Explain the 8 characteristics of living things
Be made up of cells Reproduce Based on an universal gene code Grow and develop Obtain and use materials and energy Respond to their environment Maintain a stable internal environment Evolve or change over time
Why is it misleading to describe science as a collection of facts?
Because facts are something that will always be true, such as one plus one is two. But science nothing is for certain and it is always changing as new technologies are created and new evidence is found that could contradict previous beliefs.
Why do scientists only test one variable at a time?
Because if they were to get a reaction, they wouldn't know what variable caused it if more than one variable was tested at a time.
Why aren't theories considered absolute truths?
Because science is always changing and as new evidence is uncovered a theory may be revised or replaced by a more useful explanation.
Why is water essential to all living things?
Because water is needed for chemical reactions to take place
Compare unicellular and multicellular organisms.
Both made of cells and are alive, but a unicellular organism is made up of one cell that does practically everything while multicellular organisms have many cells that work together
List the 4 macromolecules and give an example of each
Carbohydrate - Glucose, galactose, fructose (Monosaccharides), sucrose, lactose, maltose (disaccharides), starch, glycogen, cellulose (polysaccharides). protein - enzymes and hormones such as insulin Lipids- fats ( unsaturated, monounsaturated, and polyunsaturated) Nucleic Acid- DNA and RNA
What changes during a chemical reaction between two compounds?
Chemical bonds
Which structure converts light energy into chemical energy stored in food?
Chloroplast (know what it looks like)
Why is it important that carbon dioxide molecules from the atmosphere enter the calvin cycle?
Components of CO2 are used to make glucose ( the carbon and oxygen )
What are the three major roles of proteins?
Control the rate of reactions and regulate cell processes, some form important cellular structures, and some transport substances in or out of the cells and help fight diseases.
Viruses fall on the border between living and nonliving-
Despite their ability to evolve, reproduce and regulate gene expressions, which are part of the 8 characteristics of life, they cannot do this on their own and must infect a host cell first. Since they cannot thrive on their own, they are not considered alive.
Describe the charges of the three subatomic particles:
Electron - negative, neutral - neutral, proton - positive.
In the atom, which particles are in constant motions around the nucleus?
Electrons
What are the catalysts of reactions in living things?
Enzymes
Explain enzyme function
Enzymes are biological catalysts that speeds up the rate of specific biological functions by lowering the activation energy.
Difference between an experimental group and control group.
Experimental group is a group that is affected by the independent variable and from which results are seen. A control group is the group used to compare results with the independent variable to see the change and does not have the independent variable within it's experiment
In a model summarizing cellular respiration, which of the following must be represented as raw materials, or the reactants of the process.
Glucose and oxygen
Which statement best describes an event represented in the model that contributes to the production of ATP.
High-energy electrons are passes to NAD+ forming NADH
Which type of bonds hold two or more water molecules together?
Hydrogen bonds
What are produced when a base is mixed with water?
Hydroxide ions
What does it mean if a process of anaerobic? Which part of cellular respiration is anaerobic?
If a process is anaerobic it does not require oxygen. Glycolysis
Why are scientists skeptical?
If they are skeptics, then they will question existing ideas and hypothesis, and refuse to accept ideas without evidence. It is important because it leads to the testing of experiments and their credibility.
How is theory different in science then it is from the casual use of it?
In science a theory is a well-tested explanation that unifies a broad range of observations and hypotheses and enables scientists to make accurate predictions about new situations. While a normal dictionary definition will show that it's closer to a hypothesis, the scientific use of it is an explanation that was tested many times to get an the most accurate conclusion possible.
How do isotopes of an element differ?
Isotopes of an element differ in the number of neutrons in the atoms.
How does the high heat capacity of water contribute to the ability of a body of water to support life?
It contributes as it keeps the temperature of the water from changing drastically, which would lead to fish and other organisms living in the water to die as they could not adapt fast enough. Also, they will not freeze or boil in the water.
How does water's versatility as a solvent help living things survive?
It helps us as it carries nutrients and minerals and other needed substances for survival. It also helps to carry such things in our blood.
Describe the levels of organization in a multicellular organism?
It is cell to tissue to organ to organ system. A group of specialized cells form tissues, tissues that work together form organs, and a group of organs that work together to perform a specific function.
Describe the structure of the cell membrane.
It is selectively permeable and only allows substances like oxygen and carbon dioxide to pass through, but sugars and ions can not. The cell membrane is a lipid bilayer (fluid basic model on google doc with other exam reviews) with phospholipids with a polar hydrophilic head and hydrophobic nonpolar tail.
What property of water molecules allows it to be the universal solvent?
Its polarity
What can alter the rate of photosynthesis
Light (colors and intensity), Temperature (especially extremes), and Water (amount available)
Name three important factors that can affect the rate of photosynthesis?
Light, Temperature, and Water
Which organelle is known as the power plants of the cell because they transfer chemical energy from food to compounds the cell can use?
Mitochondria
What is the relationship between a monomer and a polymer.
Monomers make up polymers
By identifying the properties of water, can you predict the properties of its component elements, hydrogen and oxygen?
No, as the physical and chemical properties of a compound are usually very different from the elements it was made from.
Which type of macromolecule stores genetic info?
Nucleic Acid
Polar molecule
One side of the molecule is slightly negative while one side is slightly positive
Which of the following statements about a controlled experiment is accurate.
Only one variable can be tested at a time
What is the process by which chloroplast capture the sun's energy and convert it into food that contains chemical energy?
Photosynthesis
Compare and contrast plants and animals cells
Plants - Have chloroplast Have a cell wall Have a central vacuole Animals - Have multiple smaller vacuoles Have lysosomes
In what important ways are prokaryotic and eukaryotic cells different?
Pro - no nucleus and unraveled DNA called Chromatin. Euk - one nucleus and membrane bound organelles
Compare and contrast prokaryotic cells and eukaryotic cells
Prokaryotic cells do not contain a nucleus, and contain unraveled DNA called chromatin. Eukaryotic cells have a nucleus and membrane bound organelles.
Which type of macromolecules regulates cell processes or transports material into and out of cells?
Proteins
By measuring the height of the tortoise, the scientist is gathering What?
Quantitive data
Explain the pH scale (H+, OH-, acid, base, neutral)
Ranges from 0-14, 7 is neutral, below 7 is an acid, above 7 is a base. Look at definitions of acid, base, and pH scale. The more H+ ions, the more acidic, the more OH- ions, the more basic.
Explain what causes muscle soreness after strenuous exercise
The build up of lactic acid due to fermentation
What does the pH scale measure?
The concentration of H+ ions in a solution
Understand the carbon cycle
The interchangment of carbon between the atmospheres. About how carbon is taken in by plants and the atmospheres, and how it is released through the burning of fossil fuels, oceans, rainwater, and more.
Explain the relationship between photosynthesis and cellular respiration
The reactants of one process are the products of another, and vice versa.
How are fermentation and cellular respiration similar?
They are similar as they produce ATP for the organism they take place in, and both have glycolysis as the first step.
Why the leaves of deciduous trees change color in the fall
They change colors the accessory pigments that additionally absorb energy are no longer outnumbered by the chlorophyll because is is being broken down for energy as the winter comes and there is less sunlight for photosynthesis.
Which of the following describe the role of photosynthesis in the carbon cycle?
Transfer of carbon from the atmosphere to the biosphere
Which statement accurately describes the role of the light independent reactions?
Transferring chemical energy into high energy sugars
Why is water necessary for photosynthesis (think photolysis)
Water is necessary to replenish Hydrogens for NADP+ and gives off oxygen as a waste product
An oxygen atom has 8 protons. What can you deduce from this and why?
You can deduce that it also has 8 electrons, as the number of protons and electrons are the same. You can not deduce the number of neutrons as that would be the atomic mass minus the atomic number, and we do not have the atomic mass.
Plants use the pigment chlorophyll to
absorb sunlight
What is the name for the amount of energy that a reaction needs to get started?
activation energy
Because fermentation takes place in the absence of oxygen it is said to be
anaerobic
German scientists Schleiden and Schwann determined that the basic unit of structure and function in living things is the
cell
The process that releases energy from food in the presence of oxygen is
cellular respiration
The portion of the cell outside the nucleus is called the
cytoplasm
Solute particles move from an area of higher concentration to an area of lower concentration in a process called
diffusion
Energy is defined as the ability to
do work
Which two organelles are involved in the movement of a cell in its environment?
flagella and cilia
The first step on releasing the energy of glucose in a cell is known as
glycolysis
The relatively constant internal physical and chemical conditions that all organisms must maintain to survive is known as
homeostasis
Despite the differences in size and shape, at some point all cells have DNA and
mitochondria
Which type of organism consists of specialized cells?
multicellular eukaryotes
Which of the following is NOT form of energy.
oxygen
During heavy exercise, the buildup of lactic acid results in
oxygen debt
Properties of Water
polar molecule High heat capacity Universal solvent Less dense when frozen - expands when frozen Great transport medium for the body
Colors of white light
red, orange, yellow, green, blue, indigo, violet
Proteins are assembled on
ribosomes
The process in which two cells from different parents unite to produce a new cells is called
sexual reproduction
The rate at which materials enter and leave the cell depends on the
surface area
To be useful in science, a hypothesis must be
testable
Purpose of peer review
to ensure that the results of an experiment are correct.
Write the basic equation for photosynthesis using the names of the starting and final substance of the process.
6CO2 + 6H2O + Light Energy = 6O2 + C6H12O6 OR WITH NAMES Carbon Dioxide + Water + Light Energy = Oxygen + Sugar (Glucose)
Formula for cellular respiration
6O2 (oxygen) + C6H12O6 (Glucose) = 6CO2(Carbon Dioxide) + 6H2O (Water) + Energy (ATP)
The chemical equation for cellular respiration with molecules labeled:
6O2 (oxygen) + C6H12O6 (Glucose) = 6CO2(Carbon Dioxide) + 6H2O (Water) + Energy (ATP)
If you wanted to observe a living organism which type of microscope would you use?
A compound light microscope
Parts of cell theory
All known living things are made up of one or more cells. All living cells arise from pre-existing cells by division. The cell is the fundamental unit of structure and function in all living organisms
How does an observation differ from an inference?
An observation is looking at an object and asking questions. An inference is using what you already to know to from the question and an experiment to test it.
Autotroph
An organism that makes its own food
Which is a role of cellular respiration in cycling materials between the atmosphere and biosphere?
It transfers carbon to the atmosphere as carbon dioxide
Identify and describe the two main parts of a chloroplast where photosynthesis occurs.
The thylakoid membranes with a hollow center is where light reactions occur and the membranes are filled with chlorophyll and the stroma which is the area outside of the thylakoid membrane yet in the organelle where dark reactions occur.
How are the functions of vacuoles and lysosomes different?
The vacuoles store food and nutrients inside the cell. The lysosomes are the garbage disposal of the cell, as they contain digestive enzymes that break down old organelles, food particles, and viruses and bacteria.
What are the goals of science?
To provide natural and testable explanations for events in the natural world and to use explanations supported by data to understand patterns in nature, and to make useful predictions about natural events.
The relatively stable set of internal conditions that organisms maintain is called
homeostasis
The statement "The worm is 2 centimeters long" is an?
observation
What is the term that describes the diffusion of water through a selectively permeable membrane?
osmosis
Explain the steps of cellular respiration
---Glycolysis - the first step. Produces 2 ATP Takes place in the cytoplasm and is anaerobic. s the splitting of a 6 carbon glucose into 2 pyruvic acids, each having 3 carbons. The net gain is 2, as it takes 2 ATP to start the process and it makes 4 ATP ---Krebs Cycle- Aerobic, nicknamed Citric Acid cycle as it produces this first, takes place in the matrix of the mitochondria, Does make NADH and FADH2 and ATP, net yield of 2 ATP net yield of 6 NADH and 2 FADH2 --> sent to ETC to make more ATP, Carbon dioxide is released ---Electron Transport Chain (ETC)- In eukaryotic cells occurs on the cristae of the mitochondria, in prokaryotic cells happens on the plasma membrane, produces net yield of 36 ATP, 6 H2O are formed when the electrons unite with O2* at the end of electron transport chain.
Explain scientific methodology
-The method scientists use to find "answers" about the natural world. -Observation and questioning- observe the world around you and ask question about why things are the way they are. -Inference and hypothesis - use your basic knowledge on the subject to form a hypothesis on the question -Design a controlled experiment - plan an experiment to test your hypothesis. Divide your groups into a control and experimental group and have a dependant and independent variable. -Collect data - sample and measure or whatever you have to do to find results -Analyze conclusions - did it prove or disprove your hypothesis ?
