1.
If a pea plant were homozygous recessive for height, how would its alleles be represented?
Correct Answer
A. Tt
Explanation
If a pea plant is homozygous recessive for height, it means that it has two identical recessive alleles for the height trait. In this case, the alleles would be represented by "tt". The lowercase letters indicate the recessive allele, and having two of them shows that the plant is homozygous for the recessive trait.
2.
When an organism has two alleles at a particular locus that are different, the organism is called
Correct Answer
C. Heterozygous
Explanation
When an organism has two alleles at a particular locus that are different, it is called heterozygous. Heterozygous means that the organism has two different alleles for a specific trait. In this case, the organism has two different alleles at a particular locus, indicating that it carries both the dominant and recessive alleles for that trait. This is different from being purebred, which means that the organism has two identical alleles for a specific trait, and from being dominant or recessive, which refers to the expression of a particular allele in the phenotype.
3.
Hair color and eye color are examples of a person's
Correct Answer
B. pHenotype.
Explanation
Hair color and eye color are examples of a person's phenotype. Phenotype refers to the physical characteristics or traits that are observable and measurable in an individual. These traits are influenced by a combination of genetic factors (genotype) as well as environmental factors. In the case of hair color and eye color, these traits are determined by specific genes, but can also be influenced by factors such as sun exposure or hair dye. Therefore, the correct answer is phenotype.
4.
Mendel's second law of genetics, the law of independent assortment, is one explanation of the
Correct Answer
D. Genetic variation within species.
Explanation
Mendel's second law of genetics, the law of independent assortment, states that during the formation of gametes, the alleles for different traits segregate independently of each other. This means that the inheritance of one trait does not influence the inheritance of another trait. This independent assortment leads to a greater genetic variation within a species, as different combinations of alleles can be formed in the offspring. Therefore, the correct answer is genetic variation within species.
5.
Any of the alternative forms of a gene that occurs at a specific place on a chromosome are known as ___.
Correct Answer
B. Alleles
Explanation
Alleles are alternative forms of a gene that occur at a specific location on a chromosome. They can vary in their DNA sequence and can result in different traits or characteristics. Alleles are responsible for the genetic diversity within a population and can determine variations in physical appearance, behavior, and other traits.
6.
A chart or "family tree" that tracks which members of a family have a particular trait is called a ___.
Correct Answer
D. Pedigree
Explanation
A chart or "family tree" that tracks which members of a family have a particular trait is called a pedigree.
7.
___ studied traits of pea plants and discovered the two fundamental laws of genetics.
Correct Answer
A. Mendel
Explanation
Mendel is the correct answer because he conducted experiments on pea plants and discovered the two fundamental laws of genetics, which are the Law of Segregation and the Law of Independent Assortment. Mendel's work laid the foundation for our understanding of inheritance and genetics. Watson and Crick are known for discovering the structure of DNA, Mack is not associated with genetics, and Einstein is known for his contributions to physics, not genetics.
8.
___ is a pattern of inheritance in which the gene for a trait is located on the X-chromosome, thereby creating disorders that are much more common in males than females.
Correct Answer
D. Sex-linked
Explanation
Sex-linked inheritance refers to the pattern of inheritance where a gene for a trait is located on the X-chromosome. This means that the trait is more commonly seen in males because they only have one X-chromosome, while females have two X-chromosomes. If the gene is recessive and located on the X-chromosome, males only need to inherit one copy of the gene to express the trait, while females need to inherit two copies. This results in disorders or traits being much more prevalent in males than females.
9.
In humans, a ___ cell has ___ chromosomes.
Correct Answer
B. Haploid ... 23
Explanation
In humans, a haploid cell has 23 chromosomes. Haploid cells are cells that contain half the number of chromosomes found in diploid cells. In humans, diploid cells have 46 chromosomes, which are arranged in 23 pairs. During the process of sexual reproduction, haploid cells combine to form a diploid cell, which then develops into a new individual. Therefore, the correct answer is haploid ... 23.
10.
A form of nuclear division that divides a diploid cell into haploid cells and produces gametes is known as ___.
Correct Answer
B. Meiosis
Explanation
Meiosis is the correct answer because it is the form of nuclear division that divides a diploid cell into haploid cells and produces gametes. Mitosis is a form of cell division that results in two identical diploid cells. Cellular regeneration refers to the process of replacing damaged or lost cells, and binary fission is a form of asexual reproduction in which a cell divides into two identical cells.
11.
A cell that has two copies of each chromosome is said to be ___.
Correct Answer
A. Diploid
Explanation
A cell that has two copies of each chromosome is said to be diploid. This means that it contains two sets of chromosomes, one from each parent. Diploid cells are found in most body cells of an organism, except for gametes (sperm and egg cells) which are haploid, meaning they only have one set of chromosomes. Triploid refers to a cell or organism with three sets of chromosomes, while a gamete is a reproductive cell that is haploid.
12.
A female gamete ___.
Correct Answer
B. Is called an ovum or an egg cell.
Explanation
A female gamete is called an ovum or an egg cell. This is because in sexual reproduction, the female gamete is the reproductive cell that is capable of being fertilized by a male gamete (sperm) to form a zygote. The term "ovum" or "egg cell" is used to specifically refer to the female gamete in animals, including humans. The ovum is produced in the ovaries, not in the testes.
13.
A(n) ___ involves the insertion or deletion of a single base in a DNA molecule.
Correct Answer
A. Frameshift mutation
Explanation
A frameshift mutation involves the insertion or deletion of a single base in a DNA molecule. This type of mutation causes a shift in the reading frame of the genetic code, resulting in a completely different sequence of amino acids being produced during protein synthesis. Frameshift mutations can have significant effects on the structure and function of proteins, often leading to non-functional or malfunctioning proteins.
14.
Each set of three nucleotides on mRNA coding for an amino acid is referred to as a(n) ___.
Correct Answer
A. Codon
Explanation
A set of three nucleotides on mRNA that codes for an amino acid is known as a codon. Codons are the basic units of the genetic code and determine the sequence of amino acids in a protein. Each codon corresponds to a specific amino acid or a stop signal, and they are read by the ribosome during protein synthesis. Anticodons are found on tRNA and pair with codons during translation. Ribosomes are cellular structures where protein synthesis takes place. Base pairs are formed between nucleotides in DNA and RNA.
15.
Messenger RNA is formed in the process of ___.
Correct Answer
B. Transcription
Explanation
Messenger RNA is formed in the process of transcription. Transcription is the process by which the DNA sequence in a gene is copied into a complementary RNA molecule. This RNA molecule, known as messenger RNA (mRNA), carries the genetic information from the DNA to the ribosomes, where it is translated into a specific protein. Therefore, transcription is the correct process in which messenger RNA is formed.
16.
The process by which a DNA molecule is copied is ___.
Correct Answer
C. Replication
Explanation
The correct answer is replication. Replication refers to the process in which a DNA molecule is duplicated, resulting in two identical copies of the original DNA molecule. This process is essential for cell division and the transmission of genetic information from one generation to the next. During replication, the DNA strands separate and each strand serves as a template for the synthesis of a new complementary strand. This ensures that each daughter cell receives a complete set of genetic information. Transcription, on the other hand, is the process of synthesizing RNA from a DNA template, while translation is the process of protein synthesis. Mutation refers to a change in the DNA sequence.
17.
Watson and Crick, with the help of Rosalind Franklin, were the first to suggest that DNA is ___.
Correct Answer
C. The shape of a double helix
Explanation
Watson and Crick, with the assistance of Rosalind Franklin, proposed that DNA has the shape of a double helix. This means that DNA is structured as two strands that twist around each other in a spiral shape, resembling a twisted ladder. This discovery was groundbreaking as it provided crucial insights into the structure and function of DNA, paving the way for further advancements in the field of genetics and molecular biology.
18.
Which DNA sequence produced an mRNA strand with the sequence AGUACA?
Correct Answer
B. TCATGT
Explanation
The mRNA strand with the sequence AGUACA can be produced from the DNA sequence TCATGT. In DNA, the base pairs are A-T and G-C. When transcribing DNA to mRNA, A pairs with U and T pairs with A. Therefore, the DNA sequence TCATGT would transcribe to the mRNA sequence AGUACA.
19.
Which of the following is a pair of complementary bases?
Correct Answer
C. Thymine and adenine
Explanation
Thymine and adenine are a pair of complementary bases because they form a base pair in DNA. Adenine always pairs with thymine through two hydrogen bonds, while thymine always pairs with adenine through these same hydrogen bonds. This complementary base pairing is essential for DNA replication and the accurate transmission of genetic information.
20.
There are literally hundreds of thousands of different organic molecules. Which statement best explains how this is possible?
Correct Answer
B. Carbon is unique in that it can make four chemical bonds.
Explanation
Carbon is unique in that it can make four chemical bonds. This allows carbon atoms to form stable covalent bonds with other carbon atoms, as well as with other elements. This property of carbon enables the formation of long chains and complex structures, leading to the vast diversity of organic molecules. Other elements may have different bonding capacities, limiting the number of possible combinations and therefore the number of organic molecules they can form.
21.
Organic compounds always contain the element ____.
Correct Answer
A. Carbon
Explanation
Organic compounds are defined as compounds that contain carbon atoms bonded to hydrogen atoms. Carbon is the element that is always present in organic compounds, distinguishing them from inorganic compounds which may not contain carbon. Therefore, the correct answer is carbon.
22.
Which of the following is NOT a characteristic of RNA?
Correct Answer
B. It contains thymine.
Explanation
RNA is a nucleic acid that contains uracil instead of thymine. This is a key characteristic of RNA as opposed to DNA, which contains thymine. RNA is also typically single-stranded and plays a crucial role in transferring genetic information from DNA to the ribosome for protein synthesis. Therefore, the statement "It contains thymine" is incorrect as thymine is not found in RNA.
23.
Which of the following describes DNA?
Correct Answer
C. It controls the production of proteins.
Explanation
DNA controls the production of proteins through a process called transcription and translation. DNA contains the genetic instructions necessary for the synthesis of proteins. It carries the information in the form of genes, which are specific sequences of nucleotides. During transcription, the DNA sequence is transcribed into a messenger RNA (mRNA) molecule. The mRNA then travels to the ribosomes where translation occurs. During translation, the mRNA is used as a template to assemble the amino acids in the correct order, forming a protein. Therefore, the statement "It controls the production of proteins" accurately describes DNA.
24.
Which of the following is a structural form of carbohydrate?
Correct Answer
A. Cellulose
Explanation
Cellulose is a structural form of carbohydrate because it is a complex polysaccharide made up of glucose molecules linked together. It forms the main structural component of plant cell walls and provides rigidity and strength to the plant cells. Starch, on the other hand, is a storage form of carbohydrate, while enzyme and RNA are not carbohydrates but rather types of biomolecules involved in biological processes.
25.
Which of the following monomers make up a lipid?
Correct Answer
A. Glycerol and fatty acid
Explanation
Lipids are organic compounds that are insoluble in water and play important roles in energy storage, insulation, and protection. The monomers that make up a lipid are glycerol and fatty acids. Glycerol is a three-carbon alcohol with hydroxyl groups, and fatty acids are long hydrocarbon chains with a carboxyl group at one end. These fatty acids bond to the glycerol molecule through dehydration synthesis, forming a triglyceride. Therefore, the correct answer is glycerol and fatty acid.
26.
Which of the following is NOT a nucleotide found in DNA?
Correct Answer
D. Uracil
Explanation
Uracil is not a nucleotide found in DNA. DNA is composed of four different nucleotides: adenine, cytosine, guanine, and thymine. Uracil is found in RNA instead of DNA, where it pairs with adenine. Thymine is the nucleotide that pairs with adenine in DNA.
27.
Which of the following is a polymer of nucleotides?
Correct Answer
A. Nucleic Acid
Explanation
Nucleic acids are polymers of nucleotides, which are the building blocks of DNA and RNA. They consist of a sugar molecule (ribose or deoxyribose), a phosphate group, and a nitrogenous base (adenine, guanine, cytosine, thymine, or uracil). Nucleic acids play a crucial role in storing and transmitting genetic information, making them essential for the functioning of living organisms. Proteins, carbohydrates, and lipids are not polymers of nucleotides, but they have their own unique structures and functions in biological systems.
28.
Which of the following is a polymer of amino acids?
Correct Answer
A. Protein
Explanation
Proteins are polymers of amino acids. Amino acids are joined together through peptide bonds to form long chains, which then fold into specific three-dimensional structures. These structures determine the function of proteins in the body. Carbohydrates, lipids, and nucleic acids are not polymers of amino acids. Carbohydrates are composed of sugar molecules, lipids are composed of fatty acids, and nucleic acids are composed of nucleotides.
29.
Which phrase best describes the electron transport chain in photosynthesis?
Correct Answer
C. A series of proteins located in the thylakoid membrane
Explanation
The electron transport chain in photosynthesis is a series of proteins located in the thylakoid membrane. This chain is responsible for transferring electrons, derived from light energy, through a series of protein complexes. As the electrons move through the chain, they create a proton gradient, which is used to generate ATP. This ATP is then used in the Calvin cycle to convert carbon dioxide into glucose. Therefore, the correct answer is a series of proteins located in the thylakoid membrane.
30.
The process by which plants use sunlight to make glucose is called ___.
Correct Answer
D. pHotosynthesis
Explanation
Photosynthesis is the correct answer because it is the process by which plants use sunlight to convert carbon dioxide and water into glucose and oxygen. During photosynthesis, chlorophyll in the plant's cells captures energy from sunlight, which is then used to combine carbon dioxide and water to produce glucose. This process is essential for plants to produce food and release oxygen into the atmosphere. Mitosis is the process of cell division, cellular respiration is the process of breaking down glucose to release energy, and the cell cycle refers to the series of events that a cell goes through as it grows and divides.
31.
The main light-absorbing molecules found in plant leaves are called
Correct Answer
C. ChloropHyll
Explanation
Chlorophyll is the correct answer because it is the main light-absorbing pigment found in plant leaves. It is responsible for capturing sunlight during photosynthesis and converting it into chemical energy. Chlorophyll molecules are located within the chloroplasts, which are the organelles where photosynthesis takes place. Thylakoids and grana are structures within the chloroplasts where chlorophyll molecules are organized, but they are not the main light-absorbing molecules themselves.
32.
Which of the following statements best describes the process of photosynthesis?
Correct Answer
D. Chloroplasts absorb sunlight and store chemical energy.
Explanation
Chloroplasts are organelles found in plant cells that contain chlorophyll, which is responsible for absorbing sunlight. Through the process of photosynthesis, chloroplasts convert this sunlight into chemical energy in the form of glucose (simple sugars). This energy is then stored in the plant for later use. Therefore, the statement "Chloroplasts absorb sunlight and store chemical energy" best describes the process of photosynthesis.
33.
What is the term for the jelly-like substance that is contained inside the cell membrane?
Correct Answer
C. Cytoplasm
Explanation
Cytoplasm is the correct answer because it refers to the jelly-like substance that is enclosed by the cell membrane. It contains various organelles, such as the nucleus, and is responsible for supporting the cell's structure and housing the cell's genetic material, DNA.
34.
Which of the following is a characteristic of prophase?
Correct Answer
D. Nuclear membrane breaks down.
Explanation
During prophase, the nuclear membrane breaks down. This is an important characteristic of prophase because it allows the chromosomes, which have already replicated during interphase, to be released into the cytoplasm. Breaking down the nuclear membrane also allows for the formation of the mitotic spindle, which is necessary for the proper alignment and separation of chromosomes during cell division.
35.
What is the main function of the Golgi apparatus?
Correct Answer
C. Process and deliver proteins
Explanation
The Golgi apparatus is responsible for processing and delivering proteins within the cell. It receives proteins from the endoplasmic reticulum, modifies them by adding sugars and other molecules, and then packages them into vesicles for transport to their final destinations within the cell or for secretion outside of the cell. This process ensures that proteins are properly folded, modified, and targeted to their intended locations, allowing them to perform their specific functions within the cell.
36.
Unlike a eukaryoteic cell, a prokaryotic cell does not have...
Correct Answer
B. A nucleus.
Explanation
A prokaryotic cell does not have a nucleus. Unlike eukaryotic cells, which have a distinct nucleus that contains the cell's DNA, prokaryotic cells have their DNA scattered throughout the cytoplasm. Prokaryotic cells are simpler in structure and lack many membrane-bound organelles found in eukaryotic cells. Instead, they have a cell membrane that encloses the cytoplasm and controls the movement of substances in and out of the cell.
37.
Which organelle is the storehouse for most of a cell's genetic information?
Correct Answer
A. Nucleus
Explanation
The nucleus is the storehouse for most of a cell's genetic information. It contains the cell's DNA, which carries the instructions for the cell's functioning and development. The nucleus is surrounded by a nuclear membrane, which helps protect the genetic material from damage. Additionally, the nucleus plays a crucial role in regulating gene expression and controlling the cell's activities. Therefore, the nucleus is responsible for storing and controlling the genetic information of a cell.
38.
In the diagram to the right, what is structure B?
Correct Answer
C. Mitochondrial matrix
Explanation
The correct answer is mitochondrial matrix. The diagram likely represents a mitochondrion, which is an organelle found in eukaryotic cells. The mitochondrion is composed of an outer membrane and an inner membrane, with the space between them called the intermembrane space. Inside the inner membrane is the mitochondrial matrix, which contains enzymes involved in cellular respiration. This is where many of the metabolic reactions occur, including the citric acid cycle and the production of ATP. Therefore, structure B in the diagram is most likely representing the mitochondrial matrix.
39.
In the diagram to the right, what is structure A?
Correct Answer
A. Folded inner membrane
Explanation
Structure A in the diagram represents the folded inner membrane. This is because the folded inner membrane is a characteristic feature of mitochondria, where it increases the surface area available for cellular respiration and ATP production. The other options, such as the mitochondrial matrix, stroma, and thylakoid membrane, are associated with other cellular structures like chloroplasts and not applicable to the given diagram.
40.
The part of cellular respiration in which glucose is broken down is called
Correct Answer
D. Glycolysis.
Explanation
Glycolysis is the correct answer because it is the part of cellular respiration in which glucose is broken down. During glycolysis, glucose is converted into two molecules of pyruvate, producing a small amount of ATP and NADH. This process occurs in the cytoplasm and does not require oxygen, making it the first step in both aerobic and anaerobic respiration. Photosynthesis, on the other hand, is the process by which plants convert sunlight into energy, while aerobic respiration and electron transport occur later in cellular respiration, after glycolysis.
41.
Where does glycolysis take place?
Correct Answer
D. Cytoplasm
Explanation
Glycolysis is the metabolic pathway that converts glucose into pyruvate. It is the first step in cellular respiration and occurs in the cytoplasm of cells. In this process, glucose is broken down into two molecules of pyruvate, producing a small amount of ATP and NADH. The cytoplasm is the location where most cellular processes take place, including the initial steps of glucose metabolism. Therefore, glycolysis occurs in the cytoplasm.
42.
___ is known as the universal solvent.
Correct Answer
A. Water
Explanation
Water is known as the universal solvent because it has the ability to dissolve a wide range of substances. This is due to its unique molecular structure, with polar covalent bonds and hydrogen bonding. Water molecules are attracted to both positive and negative charges, allowing them to surround and separate solute particles, breaking them apart and forming a solution. This property of water makes it essential for many biological processes, as it can dissolve and transport nutrients, waste products, and other molecules within cells and throughout organisms.
43.
The ancient bipedal hominid called "Lucy" is a member of which species?
Correct Answer
B. Australopithecus aferensis
Explanation
Lucy, the ancient bipedal hominid, is a member of the species Australopithecus aferensis. This is because Lucy's skeletal remains, discovered in Ethiopia in 1974, exhibit characteristics that align with Australopithecus aferensis, such as a small brain size, a mix of ape-like and human-like features, and evidence of walking upright. Lucy's discovery has provided valuable insights into human evolution and our early ancestors.
44.
The ancient bipedal hominid called "Handy Man" is a member of which species?
Correct Answer
B. Homo habilis
Explanation
Homo habilis, also known as "Handy Man," is an ancient bipedal hominid species. This species lived approximately 2.4 to 1.4 million years ago and is considered one of the earliest members of the Homo genus. They were known for their tool-making abilities, which earned them the nickname "Handy Man." Homo habilis had a smaller brain size compared to later hominid species, but they were still capable of using tools and had a significant impact on human evolution.
45.
Modern humans are members of which species?
Correct Answer
D. Homo sapiens
Explanation
The correct answer is Homo sapiens because Homo sapiens refers to modern humans. Homo neanderthalensis, Homo habilis, and Homo erectus are all extinct species of hominids that lived before modern humans.
46.
Which of the following is not a monkey?
Correct Answer
B. Homo sapiens
Explanation
Homo sapiens is not a monkey because it belongs to the species of humans. Monkeys are a separate group of primates that include baboons, lemurs, and tarsiers.
47.
The oldest living primate group are the ___.
Correct Answer
C. Prosimians
Explanation
Prosimians are the oldest living primate group. They are a group of primates that includes lemurs, lorises, and tarsiers. Prosimians have been around for millions of years and are considered to be the most primitive and ancestral primates. They have retained many characteristics that were present in the earliest primates, such as a keen sense of smell and large, forward-facing eyes. Orangutans, old world monkeys, and gorillas are not part of the prosimian group and are relatively more recent in evolutionary history.
48.
Which of the following is not a characteristic of hominids?
Correct Answer
B. Prehensile tails
Explanation
Hominids are a group of primates that includes humans and their closest relatives. They are characterized by several distinct features, such as walking upright, opposable thumbs, and large brains. However, hominids do not possess prehensile tails. A prehensile tail is a specialized adaptation found in some primates, like monkeys and certain species of apes, that allows them to grasp and manipulate objects. Hominids, on the other hand, do not have this physical trait, making it the correct answer.
49.
What is the only hominid to co-exist with Homo sapiens in Europe?
Correct Answer
B. Homo neanderthalensis
Explanation
Homo neanderthalensis is the correct answer because it is the only hominid species that co-existed with Homo sapiens in Europe. Neanderthals lived in Europe and parts of Asia from approximately 400,000 to 40,000 years ago. They had a close genetic relationship with modern humans and are considered a sister species. Evidence suggests that Neanderthals had sophisticated tools, used fire, and had complex social structures. They eventually went extinct, possibly due to competition with Homo sapiens or climate change.
50.
What two groups are most hominid species classified into?
Correct Answer
A. Australopithecus and Homo
Explanation
Hominid species are classified into two main groups: Australopithecus and Homo. Australopithecus is a genus that includes various species of early hominids, such as Australopithecus afarensis. Homo, on the other hand, refers to the genus that includes modern humans and their close relatives, such as Homo habilis and Homo sapiens. These two groups represent different stages in human evolution, with Australopithecus species being more ancient and Homo species being more closely related to modern humans.