Biology Keystone Study!!!
Energy in PHOTOSYNTHESIS Energy out Energy in CELLULAR RESPIRATION Energy out A. Describe the energy changes occurring in each process.
>Photosynthesis transforms light energy into chemical energy. Photosynthesis uses the energy of sunlight to make sugars. >Cellular respiration transforms the chemical energy in glucose into chemical energy in ATP.
Describe how the structures of proteins differ from the structures of carbohydrates.
Carbohydrates are in long chains formed by sugars that are bonded together. Proteins can be in sheets or folded shapes. Carbohydrates only have carbon, hydrogen and oxygen in them.
Energy in PHOTOSYNTHESIS Energy out Energy in CELLULAR RESPIRATION Energy out B. Describe how energy transformations involved in photosynthesis are related to energy transformations involved in cellular respiration.
Cellular respiration takes the energy stored in glucose and converts it into ATP. ATP is used to run cell activities. The glucose used in cellular respiration comes from photosynthesis. Photosynthesis converts the light energy into chemical energy; cellular respiration converts this chemical energy into a more usable form for the cell.
Compare the process of potassium ion transport to another mechanism that moves material across the plasma membrane.
Compare the process of potassium ion transport to another mechanism that moves material across the plasma membrane.
Describe how different organisms having a common gene such as COII supports the theory of evolution.
Different organisms would not have the same gene by chance. If two organisms share a gene, it is likely that they shared a common ancestor who passed the gene on to each species.
Isle Royale is located in Lake Superior. Isle Royale is home to populations of wolves and moose. The interactions between the wolves and moose, as well as the individual population sizes, have been studied since 1958. The graph shows the population sizes over time for both wolves and moose. Describe one limiting factor for the moose population
Food supply is a limiting factor on an island because the moose cannot move somewhere else when their food supply runs out. Moose eat plants so there needs to be enough plants for moose to survive.
The gene COII is in the genome of many organisms. A comparison of the number of base differences between the COII gene in a rat and that of two other animals is shown. Based on the data, describe a possible evolutionary relationship between rats, mice, and cows.
Mice and rats are more closely related than rats and cows. This can be seen from the smaller number of differences in the CO11 protein.
Describe one similarity between prokaryotic cells and eukaryotic cells that is independent of size.
Prokaryotes and eukaryotes both contain ribosomes, cell walls, and cell membranes. None of these are a function of size.
Based on the structural difference, explain why prokaryotic cells can be much smaller than eukaryotic cells.
Prokaryotic cells are smaller and less complex than eukaryotic cells. Therefore, they require less genetic material. This genetic material is packaged into PLASMIDS. Eukaryotic cells require more genetic material, which they store in multiple chromosomes. These chromosomes are stored in the nucleus.
Identify a structural difference between prokaryotic cells and eukaryotic cells that is directly related to their difference in size.
Prokaryotic cells contain less genetic material and lack nuclei.
Proteins are a major part of every living cell and have many different functions within each cell. Carbohydrates also perform numerous roles in living things. Describe the general composition of a protein molecule.
Proteins are made of carbon, hydrogen, oxygene, nitrogen and some have sulfur. These elements form amino acides. Amino acids form proteins.
Describe how the functions of proteins differ from the functions of carbohydrates.
Proteins make up the enzymes that speed up the reactions in living things. Proteins also make antibodies. Carbohydrates give us energy (starch) and make plant cell walls (Cellulose)
The COII gene of a monkey has 203 base differences from the same gene in a rat and 210 base differences from the same gene in a mouse. Compare the evolutionary relationships between the monkey, the rat, and the mouse.
The COII gene of a monkey has 203 base differences from the same gene in a rat and 210 base differences from the same gene in a mouse. Compare the evolutionary relationships between the monkey, the rat, and the mouse.
Explain the process that occurs as the cell produces the ion concentration gradient.
The cell uses the energy from ATP to pump potassium ions into their cells. Special pumps within the cell membrane are used to preform this process. The ATP provides the energy to open and close these pumps.
Some animals can produce a potassium ion concentration inside their cells that is twenty times greater than that of their environment. This ion concentration gradient is maintained by the plasma membrane. Identify the process in the cell membrane that produces this difference in concentration.
The difference is created by active transport. You can identify this because in passive transport, molecules move across the membrane until the concentration on each side of the membrane is equal.
Explain one likely reason why the wolf population rapidly increased between 1975 and 1980.
The wolf population increased because they had plenty of food. Wolves can eat moose. The moose population increased between 1970-1975 so there was a lot of food for the wolves to eat on the island.
Describe how chromosome separation in meiosis is different from chromosome separation in mitosis.
There are two divisions within meiosis, meiosis I and meiosis II. During meiosis I, chromosomes line up in homologous pairs in order for the cell to be reduced from diploid to haploid. They then line up end to end in meiosis II in order to separate sister chromatids. In mitosis, chromosomes separate only once. They line up end to end. This results in two identical, diploid cells.
Compare the effects of a disorder caused by chromosomes failing to separate during meiosis, such as Patau syndrome, to the effects of chromosomes failing to separate during mitosis.
When a mutation occurs during meiosis, the organism in which the mutation occurs is not affected. However, the disorder will be passed to their offspring. Since all the cells in the offspring begin with the two parental gametes, every cell in the body of the offspring will contain the mutation. When a mutation occurs during mitosis, the organism in which the mutation occurs is affected. However, the mutation will only occur in the localized region in which the mutated cell is found. It cannot be passed.
Which statement correctly describes how nitrogen in the soil returns to the atmosphere? A. Soil bacteria convert nitrates into nitrogen gas. B. Decomposers directly convert ammonium into nitrogen gas. C. Plants assimilate nitrites and convert them into nitrogen gas. D. Nitrogen-fi xing bacteria in plant roots convert nitrates into nitrogen gas.
Answer A: Soil bacteria converts nitrates into nitrogen gas in a process known as denitrification.
A species of snapping turtles has a tongue that resembles a worm. The tongue is used to attract small fi sh. Which best describes the interaction between the fish and the snapping turtle? A. predation B. symbiosis C. parasitism D. competition
Answer A: The snapping turtle is a predator which eats fish.
Which statement describes a cell process that is common to both eukaryotic and prokaryotic cells? A. Both cell types carry out transcription in the nucleus. B. Both cell types use ribosomes to carry out translation. C. Both cell types assemble amino acids to carry out transcription. D. Both cell types carry out translation in the endoplasmic reticulum.
Answer B: Both prokaryotes and eukaryotes carry out translation on ribosomes.
Carbohydrates and proteins are two types of macromolecules. Which functional characteristic of proteins distinguishes them from carbohydrates? A. large amount of stored information B. ability to catalyze biochemical reactions C. effi cient storage of usable chemical energy D. tendency to make cell membranes hydrophobic
Answer B: Carbohydrates are unable to catalyze reactions.
Patau syndrome can be a lethal genetic disorder in mammals, resulting from chromosomes failing to separate during meiosis. Identify the step during the process of meiosis when chromosomes would most likely fail to separate.
Anaphase I or II are the most likely steps in which chromosomes would fail to separate. During Anaphase I, homolgous chromosomes are pulled to opposite sides of the cell. If the spindle fibers do not attach properly during metaphase, the homologous pairs will not separate correctly. If the homologous pairs do not separate, two will go into one cell. Anaphase II is the phase in which sister chromatids are pulled to opposite sides of the cell. If sister chromatids fail to separate, two will go into one gamete. If this gamete were fertilized it would result in a trisomy, such as Patau syndrome.
Which characteristic is shared by all prokaryotes and eukaryotes? A. ability to store hereditary information B. use of organelles to control cell processes C. use of cellular respiration for energy release D. ability to move in response to environmental stimuli
Answer A - All prokaryotes sand eukaryotes contain nucleic acids, which store hereditary information
A protein in a cell membrane changed its shape to move sodium and potassium ions against their concentration gradients. Which molecule was most likely used by the protein as an energy source? A. ATP B. ADP C. catalase D. amylase
Answer A: ATP is used to power active transport.
A scientist observes that, when the pH of the environment surrounding an enzyme is changed, the rate the enzyme catalyzes a reaction greatly decreases. Which statement best describes how a change in pH can affect an enzyme? A. A pH change can cause the enzyme to change its shape. B. A pH change can remove energy necessary to activate an enzyme. C. A pH change can add new molecules to the structure of the enzyme. D. A pH change can cause an enzyme to react with a different substrate.
Answer A: Enzymes are substrate-specific due to the shape of their active sites. Changes in pH, temperature causes the proteins that make-up the enzymes to denature. This changes their shapes and prevents them from catalyzing reactions.
Genetic engineering has led to genetically modified plants that resist insect pests and bacterial and fungal infections. Which outcome would most likely be a reason why some scientists recommend caution in planting genetically modified plants? A. unplanned ecosystem interactions B. reduced pesticide and herbicide use C. improved agricultural yield and profit D. increased genetic variation and diversity
Answer A: Genetically modified plants may spread their genes to wild plants during pollination, which cannot be controlled in the outdoor environment. This may result in genes for resistance being spread into ecosystems, causing unintended results.
A genetic mutation resulted in a change in the sequence of amino acids of a protein, but the function of the protein was not changed. Which statement best describes the genetic mutation? A. It was a silent mutation that caused a change in the DNA of the organism. B. It was a silent mutation that caused a change in the phenotype of the organism. C. It was a nonsense mutation that caused a change in the DNA of the organism. D. It was a nonsense mutation that caused a change in the phenotype of the organism.
Answer A: Silent mutations change the genetic code of the DNA, but do not result in changes to the protein function. therefore, the phenotype of the organism is not affected.
The skeletons of mammalian forelimbs represent variations of a structure that was present in their common ancestor. What has most likely caused the variation in forelimbs? A. changes in muscle structure B. changes in the genetic codes C. trait formation due to behaviors D. development of vestigial structures
Answer B: Changes in the genetic codes would be needed to make a change in pheneotype.
Photosynthesis and cellular respiration are two major processes of carbon cycling in living organisms. Which statement correctly describes one similarity between photosynthesis and cellular respiration? A. Both occur in animal and plant cells. B. Both include reactions that transform energy. C. Both convert light energy into chemical energy. D. Both synthesize organic molecules as end products.
Answer B: Photosynthesis transforms the energy in sunlight into chemical energy in glucose. Cellular respiration transforms the energy in glucose into ATP.
A farmer observed that an increase in a fi eld's soil nitrogen content was followed by an increase in producer productivity. What does this observation most likely indicate about the relationship between nitrogen and the producers in the fi eld? A. Nitrogen was a biotic factor. B. Nitrogen was a limiting factor. C. Nitrogen became a surplus resource. D. Nitrogen became a selection pressure.
Answer B: a limiting factor is something required for an ecosystem to maintain growth. When it is absent, growth stops. In this instance, the primary productivity increased with the application of nitrogen, indicating that it was the factor preventing growth in the ecosystem.
Using a microscope, a student observes a small, green organelle in a plant cell. Which energy transformation most likely occurs fi rst within the observed organelle? A. ATP to light B. light to chemical C. heat to electrical D. chemical to chemical
Answer B: chloroplasts use light energy to create chemical energy in the form of glucose.
A sodium-potassium pump within a cell membrane requires energy to move sodium and potassium ions into or out of a cell. The movement of glucose into or out of a cell does not require energy. Which statement best describes the movement of these materials across a cell membrane? A. Sodium and potassium ions move by active transport, and glucose moves by osmosis. B. Sodium and potassium ions move by active transport, and glucose moves by facilitated diffusion. C. Sodium and potassium ions move by facilitated diffusion, and glucose moves by osmosis. D. Sodium and potassium ions move by facilitated diffusion, and glucose moves by active transport.
Answer B: sodium and potassium require energy, which is active transport. Glucose moves without energy, which is a form of passive transport. Glucose is large, therefore requires facilitated diffusion.
Carbon dioxide and oxygen are molecules that can move freely across a plasma membrane. What determines the direction that carbon dioxide and oxygen molecules move? A. orientation of cholesterol in the plasma membrane B. concentration gradient across the plasma membrane C. confi guration of phospholipids in the plasma membrane D. location of receptors on the surface of the plasma membrane
Answer B:: Molecules diffuse down the concentration gradient, from high to low concentration.
Agricultural runoff can carry fertilizers into lakes and streams. This runoff can cause algae populations to greatly increase. Which effect does this change in the algae population sizes most likely have on affected lakes and streams? A. an increase in water level B. an increase in water clarity C. a reduction in dissolved oxygen needed by fi sh and shellfi sh D. a reduction in temperature variations near the water's surface
Answer C: Algal blooms lead to eutrophication, a process in which algae die and decompose. This leads to the removal of large quantities of oxygen to the water. Eventually, even decomposition stops and the body of water is filled with half-decomposed algae.
A mutation occurs in the genes that code for coat color in deer. Which change will most likely result from this mutation? A. a change in the selection pressures acting on coat color B. a change in the coat-color genes of deer predator species C. an increase in coat-color diversity in the population D. an increase in the number of genes for coat color in the population
Answer C: An additional gene for coat color will definitely change the coat color diversity.
Observations • two grey wolves • five moose • several species of conifer trees • large granite rock • shallow pond A student wrote several observations in a fi eld notebook. Which term best classifi es all of the student's observations? A. population B. food chain C. ecosystem D. community
Answer C: An ecosystem contains both the biotic and abiotic factors in an area.
Which statement best compares the energy transformations of photosynthesis and cellular respiration? A. Only photosynthesis uses oxygen to create energy. B. Only photosynthesis causes an increase in kinetic energy. C. Photosynthesis and cellular respiration both store energy in chemical bonds. D. Photosynthesis and cellular respiration both require chemical energy to make food.
Answer C: Both photosynthesis and cellular respiration store energy within the bonds of sugar and/or ATP molecules.
Which statement best describes a difference between prokaryotic cells and eukaryotic cells? A. The presence of both DNA and ribosomes in prokaryotic cells indicates that they are more complex than eukaryotic cells. B. The larger size of prokaryotic cells indicates that they are more complex than eukaryotic cells. C. The presence of membrane-bound organelles in eukaryotic cells indicates that they are more complex than prokaryotic cells. D. The larger size of eukaryotic cells indicates that they are more complex than prokaryotic cells.
Answer C: Eukaryotes are more complex because they have organelles that are membrane bound, such as the nuclei which contain their DNA. Prokaryotes have DNDA, but it is not bound by a membrane as in eukaryotes.
The endoplasmic reticulum is a network of membranes within the cell, and it is often classifi ed as rough or smooth, depending on whether there are ribosomes on its surface. Which statement best describes the role of rough endoplasmic reticulum in the cell? A. It stores all proteins for later use. B. It provides an attachment site for larger organelles. C. It aids in the production of membrane and secretory proteins. D. It stores amino acids required for the production of all proteins.
Answer C: Ribsomes are housed on the rough ER. This is where translation occurs.
The rough endoplasmic reticulum and Golgi apparatus work together in eukaryotic cells. What is one way that the rough endoplasmic reticulum assists the Golgi apparatus? A. It assembles nucleic acids from monomers. B. It breaks down old, damaged macromolecules. C. It packages new protein molecules into vesicles. D. It determines which protein molecules to synthesize.
Answer C: The ER packages proteins into vesicles in order to transport them to the golgi, where they are modified.
Which statement correctly describes how carbon's ability to form four bonds makes it uniquely suited to form macromolecules? A. It forms short, simple carbon chains. B. It forms large, complex, diverse molecules. C. It forms covalent bonds with other carbon atoms. D. It forms covalent bonds that can exist in a single plane.
Answer C: The ability of carbon to bond with itself and other elements is what allows it to form macromolecules
A researcher observing an ecosystem describes the amount of sunlight, precipitation, and type of soil present. Which factors is the researcher most likely describing? A. biotic factors in a forest B. biotic factors in a tundra C. abiotic factors in a prairie D. abiotic factors in an ocean
Answer C: The abiotitc factors listed include soil, making this the only likely option.
Which statement best describes an effect of the low density of frozen water in a lake? A. When water freezes, it contracts, decreasing the water level in a lake. B. Water in a lake freezes from the bottom up, killing most aquatic organisms. C. When water in a lake freezes, it fl oats, providing insulation for organisms below. D. Water removes thermal energy from the land around a lake, causing the lake to freeze.
Answer C: water on the top of the lake freezes first, due to the low density of frozen water. This allows the water underneath to remain liquid. This allows aquatic organisms to live through the winter.
In North America, the eastern spotted skunk mates in late winter, and the western spotted skunk mates in late summer. Even though their geographic ranges overlap, the species do not mate with each other. What most likely prevents these two species from interbreeding? A. habitat isolation B. gametic isolation C. geographic isolation D. reproductive isolation
Answer D: All of these choices are reproductive isolation. These skunk species mate at different times, which is an example of temporal isolation. This is the best answer as temporal isolation is a type of reproductive isolation.
Substance A is converted to substance B in a metabolic reaction. Which statement best describes the role of an enzyme during this reaction? A. It adjusts the pH of the reaction medium. B. It provides energy to carry out the reaction. C. It dissolves substance A in the reaction medium. D. It speeds up the reaction without being consumed.
Answer D: Enzymes speed up the rate of chemical reactions by lowering the activation energy needed to start the reaction. Enzymes are not used up by this and can be reused.
Mitosis and meiosis are processes by which animal and plant cells divide. Which statement best describes a difference between mitosis and meiosis? A. Meiosis is a multi-step process. B. Mitosis occurs only in eukaryotic cells. C. Meiosis is used in the repair of an organism. D. Mitosis produces genetically identical daughter cells.
Answer D: Mitosis produces genetically identical cells; meiosis produces genetically different cells.
Living organisms can be classified as prokaryotes or eukaryotes. Which two structures are common to both prokaryotic and eukaryotic cells? A. cell wall and nucleus B. cell wall and chloroplast C. plasma membrane and nucleus D. plasma membrane and cytoplasm
Answer D: Prokaryotes and Eukaryotes have cytoplasm and MAY have cell walls.
Alveoli are microscopic air sacs in the lungs of mammals. Which statement best describes how the structure of the alveoli allows the lungs to function properly? A. They increase the amount of energy transferred from the lungs to the blood. B. They increase the flexibility of the lungs as they expand during inhalation. C. They increase the volume of the lungs, allowing more oxygen to be inhaled. D. They increase the surface area of the lungs, allowing efficient gas exchange.
Answer D: The millions of alveoli in mammals greatly increase the surface area of the lungs thereby providing a larger surface area for gas exchange.
Which process helps to preserve the genetic information stored in DNA during DNA replication? A. the replacement of nitrogen base thymine with uracil B. enzymes quickly linking nitrogen bases with hydrogen bonds C. the synthesis of unique sugar and phosphate molecules for each nucleotide D. nucleotides lining up along the template strand according to base pairing rules
Answer D: The template strand provides the enzymes with the correct nucleotide order. the order of the nucleotides is how the genetic information is store.
Which example is an activity that a fish most likely uses to maintain homeostasis within its body? A. using camoufl age to avoid predators B. feeding at night to regulate body temperature C. moving to deeper water to regulate metabolic wastes D. exchanging gases through its gills to regulate oxygen levels
Answer D: fish exchange oxygen and carbon dioxide between their bodies and the water in order to maintain appropriate oxygen levels.
In a flowering plant species, red flower color is dominant over white flower color. What is the genotype of any red-flowering plant resulting from this species? A. red and white alleles present on one chromosome B. red and white alleles present on two chromosomes C. a red allele present on both homologous chromosomes D. a red allele present on at least one of two homologous chromosomes
Answer D: since red is dominant, only one chromosome needs a red allele in order for the plant to have red flowers.
Predict what will happen to the moose population's size after 1994 by describing the shape of the curve. In your answer, be sure to explain the reasoning behind your prediction.
The moose line could level out and become almost flat. This means the moose have reached carrying capacity for the island. The wolf line would likely level out, too. The mouse line cannot continue to go up because the moose will run out of food with too many animals on the island.
