Biology

A biomass pyramid of an ecosystem is shown. Which statement provides the best explanation for the difference in biomass of organisms found at each trophic level? a. Organisms at higher trophic levels have less energy available to them than organisms at lower trophic levels. b. Organisms at higher trophic levels require smaller habitats than organisms at lower trophic levels. c. Organisms at lower trophic levels provide less energy than organisms at higher trophic levels. d. Organisms at lower trophic levels outcompete organisms at higher trophic levels.

A

A sequence of a DNA template strand is shown. ​3' TCC AAT GGC TTA TTT GCA 5' Which of these is the correct amino acid chain produced from the DNA template strand? a. Arginine - Leucine - Proline - Asparagine - Lysine - Arginine b. Tryptophan - Phenylalanine - Leucine - Glycine - Asparagine - Phenylalanine c. Serine - Leucine - Proline - Asparagine - Lysine - Arginine d. Tryptophan - Phenylalanine - Leucine - Glycine - Asparagine - Serine

A

Cells typically respond to DNA damage in three ways: by ceasing to grow and divide until the damage is repaired, by permanently ceasing to grow and divide, or by dying. In 2010 a group of scientists reported that a certain kind of immune reaction can cause DNA damage that leads to a fourth response. DNA damage can turn off genes involved in cell-signaling pathways. Turning off these genes can cause less-mature cells to divide too rapidly, often leading to the development of - a. tumors b. allergies c. hemophilia d. cardiovascular disease

A

Enzymes are proteins that help increase the rate of chemical reactions inside cells. These proteins are composed of many simpler molecules called amino acids. Which of the following suggests that the shape of an enzyme determines the enzyme's function? a. Enzymes are specific to a substrate. b. Enzymes can operate in wide range of conditions. c. Enzymes are activated by neighboring molecules. d. Enzymes can be found in all life-forms.

A

Models of the human immunodeficiency virus (HIV) and an animal cell are shown below. What is the difference in the function of the glycoprotein structures of an HIV virion and the cilia of an animal cell? a. The glycoprotein structures are used for attachment, and the cilia are used to move fluids surrounding the cell. b. The glycoprotein structures are used to obtain nutrition, and the cilia are used to secrete proteins. c. The glycoprotein structures are used to provide physical support for the viral envelope, and the cilia strengthen the cell membrane. d. The glycoprotein structures are used for defense, and the cilia are used for locomotion.

A

Proteins and carbohydrates have many functions in the body of an organism. Specific proteins and carbohydrates perform specific tasks. Information about a protein and a carbohydrate is given below. How are ferritin and glycogen similar in their primary functions for an organism? a. Both store materials needed by the organism. b. Both store energy used by the organism. c. Both support the structure of the organism. d. Both store information for the organism.

A

The Indian leaf butterfly has traits that allow it to resemble a leaf. The bright colors of the monarch butterfly indicate that the butterfly tastes bad and can be poisonous. How does the appearance of these butterflies help them to survive? a. The Indian leaf butterfly is able to avoid predators while the monarch butterfly warns predators away. b. The Indian leaf butterfly frightens predators away while the monarch butterfly poisons predators before they can eat it. c. Both butterflies rely on camouflage to avoid predation. d. Both butterflies cooperate with on another to avoid predation.

A

The San Marcos salamander, Eurycea nana, is a light reddish-brown translucent salamander about 2-5 cm in length. E. nana is found only in Spring Lake and a portion of the San Marcos River. Which human activity would most likely decrease the ability of the salamanders to survive? a. Increasing water consumption that decreases the flow of clean water from the spring that feed the river. b. Public transportation that reduces the number of automobiles that contribute to pollution runoff into the river. c. Tourism that helps fund the educational programs related to river ecosystem conservation d. The addition of a new food source into the river that limits competition for resources.

A

The energy pyramid below shows the energy made available by producers. Based on the energy flow between trophic levels in an energy pyramid, how much energy would be expected to be found at the secondary consumer level in this pyramid? a. 100 joules b. 500 joules c. 1,000 joules d. 50 joules

A

The ocean sunfish (Mola mola) is a large, flat fish that spends most of its time in deep water feeding mainly on jellyfish. Sunfish often have many species of copepods, small crustaceans, that bury their heads into the soft tissue of the sunfish. Sunfish will swim to the surface of the water and lie sideways, allowing seabirds to eat the copepods from their skin. Which list describes the types of relationships the sunfish has with other marine organisms? a. ​Seabirds: mutualism ​Jellyfish: predation ​Copepods: parasitism b.​Seabirds: parasitism ​Jellyfish: commensalism ​Copepods: predation c.​Seabirds: predation ​Jellyfish: mutualism ​Copepods: commensalism d. ​Seabirds: commensalism ​Jellyfish: parasitism ​Copepods: mutualism

A

When cells lose their ability to regulate the cell cycle, they can divide at an accelerated rate and form a mass of cells. This mass of cells is referred to as - a. a tumor b. an embryo c. a gland d. an organ

A

including homeostasis and transport of molecules. A type of cellular transport is shown. Which description best identifies this type of cellular transport? a. Active transport, because energy is being used to move molecules against the concentration gradient. b. Facilitated diffusion, because energy is being used to move molecules with the concentration gradient. c. Osmosis, because energy is not being used to move molecules with the concentration gradient. d. Endocytosis, because energy is not being used to move molecules against the concentration gradient.

A

A partial Texas food web is shown. The populations of which organisms will most likely increase as a result of a disease that suddenly reduced the population of Texas horned lizards? a. Grasses and ants b. Ants and grasshoppers c. Grasshoppers and Texas cottonmouths d. Texas cottonmouths and red-shouldered hawks

B

A science class is planning a field trip to a local farm that has a large pond. Which of the following lists the order of biological organization from smallest to largest that the students can expect to find at the pond? a. organism, community, population, ecosystem b. organism, population, community, ecosystem c. population, organism, community, ecosystem d. population, organism, ecosystem, community

B

A student researching bacteria concluded a report with the claim in the box. Which statement correctly addresses the validity of the claim? a. The claim is valid because many studies and experiments have shown that bacteria disrupt homeostasis. b. The claim is invalid because there are many types of bacteria that help organisms maintain homeostasis. c. The claim is invalid because only microorganisms such as viruses disrupt the health of organisms. d. The claim is valid because bacteria cause disease.

B

As part of the nitrogen cycle, animals acquire some amino acids by doing which of the following? a. Breathing air b. Eating plants c. Drinking water d. Producing waste

B

Enzymes are proteins that have a three-dimensional shape that is specific to a particular substrate. Environmental conditions can change the shape of the protein. What is the most likely result if the shape of the enzyme changes? a. The substrate will change its shape to match the enzyme. b. The enzyme will no longer be able to catalyze the reaction with the substrate. c. The products made from the enzyme and the substrate will be changed. d. The enzyme will be able to bind to more diverse substrates than before.

B

Grassland ecosystems in Texas have evolved to depend on periodic fires to return nutrients to the soil and encourage plant reproduction. Humans have prevented fires in many of these grassland areas, resulting in plant and animal communities with little diversity. Wildlife biologists often recommend purposefully starting fires called prescribed burns, which are monitored and controlled, in grassland ecosystems every 3 to 4 years. These biologists observe greater diversity in plant and animal life in the years following a prescribed burn. What natural processes are the biologists attempting to imitate? a. Biomagnification b. Succession c. Population bottleneck d. Species extinction

B

In a study of physical endurance, researchers observed significant increases in the heart rates and breathing rates of participants immediately after they engaged in strenuous exercises. a. The water concentration in the blood increases. b. Body cells require increased oxygen as energy is expended. c. Muscle cells increase in temperature and require fluid to reduce the temperature. d. An increase in muscle activity causes increases in glucose levels in red blood cells.

B

Oncogenes are mutated forms of genes. Oncogenes can transform a cell into a tumor cell. Some tumor cells are benign, while others are malignant. How does the presence of an oncogene lead to the formation of a tumor? a. ATP production is inhibited b. Cell division is unregulated c. Somatic cell growth is inhibited d. Antibody activity is unregulated

B

Some species of millipedes will roll into a ball when threatened, while other species of millipedes can secrete noxious chemicals from their bodies. These adaptations allow the millipedes to - a. survive in different temperatures b. avoid different types of predators c. conserve different amounts of energy d. blend into different types of environments

B

Students are modeling mRNA during the process of protein synthesis. Which answer choice correctly describes the model of the mRNA strand being transcribed? a. The mRNA strand is complementary to the DNA template strand; however, uracil instead of adenine is paired with thymine. b. The mRNA strand is complementary to the DNA template strand; however, uracil instead of thymine is paired with adenine. c. The mRNA strand is an exact copy of the DNA template strand; however, uracil instead of adenine is paired with thymine. d. The mRNA strand is an exact copy of the DNA template strand; however, uracil instead of thymine is paired with adenine.

B

Students use a microscope to look for structures present in four different cells. The students placed an X for each structure that was viewed for each cell on the table shown. Which cell that was viewed is most likely a prokaryote? a. Cell W b. Cell X c. Cell Y d. Cell Z

B

Telophase is a stage of a cellular process that begins after the chromosome have moved to opposite poles of the cell. During which cellular process does telophase occur? a. Translation b. Interphase c. Transcription d. Mitosis

B

The diagram below represents the nitrogen cycle in a student's aquarium. Ammonia, nitrites, and, to a lesser degree, nitrates can be harmful to fish. The student wants to keep the nitrogen in this aquarium cycling normally without having to continually change the water. Which of the following should the student add more of to help remove nitrates and improve the natural cycling of nitrogen in this aquarium? a. Fish b. Plants c. Nitrobacter d. Water

B

The diagram shows cells in different phases of mitosis. The student is trying to find a cell in a particular phase of mitosis. The student is looking for evidence that spindle fibers are separating the chromosomes to ensure that each new nucleus has one copy of each chromosome. Which cell is in the phase of mitosis that the student is searching for? a. Cell 1 b. Cell 2 c. Cell 3 d. Cell 4

B

The graphs show the reaction rate for an enzyme across a range of temperatures and pH. Based on these data, this enzyme functions best at what temperature and pH? a. Temperature of 27°C and a pH of 4 b. Temperature of 37°C and a pH of 6 c. Temperature of 40°C and a pH of 8 d. Temperature of 50°C and a pH of 10

B

The model shows a mutation to a partial sequence of bases in a gene. Which type of mutation does the model demonstrate? a. Deletion b. Insertion c. Substitution d. Translocation

B

When constructing an energy pyramid of the swamp ecosystem, which of these would be placed at the top of the pyramid? a. Grass carp b. American alligator c. Eastern mud turtle d. Great blue heron

B

Which components bond with adenine in a section of double-stranded DNA? a. 1, 3, 5, and 6 only b. 3 and 5 only c. 2 and 4 only d. 3, 4, 7, and 8 only

B

Which of the following correctly describes how a diagram of cellular respiration would differ from a diagram of photosynthesis? a. The cellular-respiration diagram would show electromagnetic waves as the final product. b. The cellular-respiration diagram would show glucose as the main source of energy. c. The cellular-respiration diagram would show energy stored in large protein molecules. d. The cellular-respiration diagram would show water as the main source of chemical energy.

B

complexity. Some students used information they gathered from lab investigations to prepare a table. They entered the table in their lab notebooks. Which of these correctly identifies the two cells described in the table? a. Cell 1 eukaryotic, and Cell 2 is prokaryotic. b. Cell 1 is prokaryotic, and Cell 2 is eukaryotic. c. Both Cell 1 and Cell 2 are eukaryotic. d. Both Cell 1 and Cell 2 are prokaryotic.

B

A mutation in which types of cells would only affect the organism and not future generations? a. egg cell and liver cell b. sperm cell and egg cell c. nerve cell and brain cell d. sperm cell and lung cell

C

Part of an important cellular process involving a DNA strand is modeled below. What is the purpose of this cellular process? a. Preserving genetic information for future generations b. Deleting the information in the sequence produced from the DNA template c. Transcribing information in the DNA sequence for use by the cell d. Producing more nucleotides for the DNA sequence

C

Photosynthesis and cellular respiration both involve the use and release of gases. Which statement correctly identifies the role of gases in the two processes? a. Photosynthesis and cellular respiration both use carbon dioxide and release oxygen. b. Photosynthesis and cellular respiration both use oxygen and release carbon dioxide. c. Cellular respiration uses oxygen and releases carbon dioxide, while photosynthesis uses carbon dioxide and releases oxygen. d. Cellular respiration uses carbon dioxide and releases oxygen, while photosynthesis uses oxygen and releases carbon dioxide.

C

Roads are often built through forests for industrial purposes or as land is developed for residential and commercial needs. How would road construction through a forest most likely affect the ecosystem? a. Non-native species would replace native species. b. The number of primary consumers would increase. c. The natural succession of vegetation would change. d. All producers would be eliminated from the community.

C

The karyotype, or chromosomal profile, for humans is shown. A karyotype can be used to investigate genetic disorders. The chemical colchicine is used in the production of karyotypes. Colchicine prevents spindle fibers from forming during the cell cycle. What is a result of preventing spindle fibers from forming? a. The cell cycle skips G0 phase and repeats G1 phase. b. Mitotic division is skipped, and the cell cycle proceeds to cytokinesis. c. Mitotic division stops in metaphase and cannot proceed to anaphase. d. The cell cycle skips S phase and proceeds to G2 phase.

C

Transmembrane proteins span the width of cell membranes. Four types of transmembrane proteins are shown in a section of cell membrane. Although these proteins have different specific functions, they all - a. stop chemical reactions within the cell b. synthesize molecules that signal other cells c. help the cell interact with its external environment d. remove large waste particles from the cytoplasm of the cell

C

What would be the most likely effect of a wildfire that burned a large area of a forest? a. More sugars and starches would be available for animals in the area. b. The availability of fossil fuels for use by industries in the area would be reduced. c. Less carbon dioxide would be removed from the atmosphere in the area by plants. d. An increase in animal respiration would increase the release of carbond dioxide in the area.

C

Which answer choice best describes a community? a. Praying mantises caring for their young b. Three-spined sticklebacks living in estuaries c. Different species of lizards occupying the same niche in a desert d. Roosting mother bats recognizing their offspring

C

Which part of a DNA molecule is responsible for the direct coding of specific traits in an organism? a. The number of hydrogen bonds that hold the strands of DNA together. b. The number of carbons in the DNA molecule. c. The sequence of nucleotide bases in the DNA molecule. d. The sequences of phosphates along each DNA strand.

C

Which table shows the two steps of DNA replication?

C

cells. A student produces a labeled drawing of a virus for a presentation. The student states that the capsid has a function similar to the nuclear membrane found in animal cells. Which of these describes the similar functions of capsids and nuclear membranes? a. Both transport proteins throughout the structures. b. Both provide energy for activities in the structures. c. Both protect genetic information for the structures. d. Both code for the proteins needed for reproduction of the structures.

C

On March 24, 1989, an oil tanker ran aground on Bligh Reef in Prince William Sound, Alaska, and spilled millions of liters of crude oil. The graph shows pink salmon populations in Prince William Sound from 1970 to 1999. What do these data suggest about the effect the oil spill had on pink salmon? a. Pink salmon were nearly eliminated after the oil spill. b. Pink salmon populations steadily declined in the 10 years following the spill. c. Pink salmon populations declined and never fully recovered. d. Pink salmon populations seemed to be minimally affected.

D

The diagram shows molecules that a mitochondrion uses and produces during a cellular process. Which other molecule is a product of this process? a. DNA b. RNA c. C6H12O6 d. ATP

D

The diagrams show a partial food web containing the Glyptapanteles wasp and the life cycle of this wasp. Based on the two diagrams, which list correctly identifies the relationships Glyptapanteles wasp larvae have with other organisms? D C B A

Competition: stink bugs Parasitism: geometrid moths

A segment of DNA produces methionine, threonine, histidine, aspartate, and glycine when translated. A substitution mutation occurs and causes the synthesis of the segment as shown. New DNA strand: 3' -TACAGGGTGCTACCACT- 5' Which is the new peptide chain when the new DNA segment is translated? a. Methionine, phenylalanine, histidine, aspartate, glycine b. Methionine, phenylalanine, histidine, aspartate, glycine c. Methionine, proline, histidine, aspartate, glycine d. Methionine, serine, histidine, aspartate, glycine

D

A segment of a DNA strand is shown. 3' AGGTCAGGT 5' Which of these is the correct complementary DNA strand for the segment shown? a. 5' AGGTCAGGT 3' b. 5' ACCUGAGGU 3' c. 5' TGGACTGGA 3' d. 5' TCCAGTCCA 3'

D

During secondary succession, which of these best describes why decomposing pioneer plants give way to larger, more complex plant species, such as hardwood trees? a. Increased amounts of sunlight are able to reach the ground while the pioneer species are decomposing. b. Increased soil temperatures from decomposing pioneer species help tree seeds germinate more quickly. c. Increased amounts of decomposing pioneer species remove nutrients that tree seedlings need to grow and mature. d. Increased amounts of soil from decomposing pioneer species allow plants with more extensive root systems to become established.

D

n 1952 Rosalind Franklin took the x-ray photograph shown below, which gave the world its first look at DNA. By studying this photograph, scientists gained knowledge about the - a. role of DNA in protein synthesis b. mutation of nucleotide sequences in DNA c. sequence of DNA that makes up the human genome d. double-helix structure of DNA

D