Bio 3.01

By the end of mitosis, _______ cells are produced, whereas by the end of meiosis, _______ cells are produced. A two; four B one; three C three; one D four; two

A

DNA contains instructions for making the different molecules that a cell needs to grow and function. For example, _______ is made by _______. A a protein; translating mRNA B a protein; transcribing mRNA C mRNA; transcribing proteins D mRNA; translating DNA

A

DNA is a type of _______ that contains the genetic instructions of an organism's development and functioning. A nucleic acid B lipid C protein D carbohydrate

A

Diseases may be caused by genetic factors, such as mutations in reproductive cells or the inheritance of disease-causing traits. They may also be caused by environmental factors, such as inhaling polluted air. Which of the following personal decisions may also cause a disease? A eating food that is high in fat and low in vitamins B being bitten by a mosquito carrying an infectious disease C being exposed to radiation during an accidental nuclear meltdown D receiving infected blood in a hospital during a needed surgery

A

The diagram below shows how cancer cells form. According to the diagram, what is the primary cause of cancer? A mutations B genes C cells D DNA

A

What are the three main components of a DNA molecule? A a sugar, a phosphate group, and a nitrogenous base B a sugar, a phosphate group, and an amino acid C a sugar, a nucelotide, and an amino acid D a sugar, a water molecule, and a nitrogenous base

A

When mitosis occurs, the DNA inside the cell's nucleus must replicate. The new cell that is formed has an identical copy of its parent cell's DNA. That means it has the same information coded in its genes. During DNA replication, how is an accurate new copy of DNA formed? A DNA polymers add nucleotides to the exposted base pairs according to base-pairing rules. B During DNA replication uracil bases hold the place of all thymine bases until the newly formed double helix is able to form hydrogen bonds. C DNA helicases add nucleotides to the exposed bases and ensure the formation of hydrogen bonds. D Replication forks ensure that DNA polymerases cannot attach to the old DNA molecule.

A

Which choice below correctly shows the base pairing rules in DNA? A A - T G - C B A - G C - T C A - C T - G D A - U G - C

A

Which of the following is a source of genetic variation in sexually-reproducing organisms? A meiosis B translation C mitosis D all of these

A

Which of the following is true regarding the process shown above? A The process shown above is known as translation and involves the production of proteins from RNA B The process shown above is known as cloning and involves the production of RNA from protein molecules C The process shown above is known as replication and involves the production of DNA from RNA D The process shown above is known as transcription and involves the production of proteins from DNA.

A

Cancer is a disease that usually results when A a bacterium enters the body through a person's skin B mutations cause a person's body cells to divide u ncontrollably C a person has limited exposure to sunlight D a person has a severe allergic reaction

B

During sexual reproduction, gametes, or sex cells, are produced through the process of meiosis. How many chromosomes should be in each cell labeled with an X? A 4 B 16 C 32 D 8

B

During the process shown above, the two strands of one DNA molecule are unwound. Then, DNA polymerases add complementary nucleotides to each strand which results in the formation of two identical DNA molecules. This process is known as DNA _______. A translation B replication C cloning D transcription

B

How are the processes of mitosis and meiosis similar to each other? A Both processes involve only one division of cellular materials B Both processes begin with similar events, including chromosome replication C Both processes end with the same number of chromosomes present in each cell D Both processes result in the same number of cells produced

B

In which of the following ways does genetic information typically flow in an organism? A RNA--> proteins --> DNA B DNA --> RNA --> proteins C DNA --> proteins --> RNA D proteins --> RNA --> DNA

B

Look at the diagram of DNA below. Which of the following parts of the diagram represents the hydrogen bond that holds the two strands of DNA together? [Key: yellow-A, green-T, red-G, blue-C] A W B Y C X D W and Y

B

Sickle-cell anemia is a genetic disorder in which red blood cells take on an abnormal crescent shape. People who do not have sickle-cell anemia possess the following nucleotide and amino acid sequences: CTG ACT CCT GAG GAG AAG TCT Leu Thr Pro Glu Glu Lys Ser People who do have sickle-cell anemia possess the following nucleotide and amino acid sequences: CTG ACT CCT GTG GAG AAG TCT Leu Thr Pro Val Glu Lys Ser Sickle-cell anemia is an example of A crossing-over B a gene mutation C nondisjunction D a chromosomal mutation

B

Some traits, such as earlobe attachment, blood type, and the presence or absence of dimples, have limited variation throughout the human population because they are controlled by a single gene. Other traits, such as skin color and human height, are widely variable throughout the human population because A they are controlled by only one gene B they are controlled by more than one gene C they cannot be affected by environmental factors. D cancer

B

The Punnett square below represents a cross that produced two plants with orange flowers. If the orange color of the flowers is a result of incomplete dominance, what color were the flowers on the parent plants? A red and orange B orange and orange C yellow and orange D red and yellow

B

The Punnett square below shows the genotypes for offspring produced from a cross between a red cow and a white bull. If all of the offspring have roan coats—white hairs mixed into a base coat of red—what can be said about the red and white alleles for coat color? A They are sex-linked B They are codominant C White is dominant and red is recessive D Red is dominant and white is recessive

B

Which of the following describes an allele whose characteristic phenotype is masked by the presence of a second, different allele? A dominant B recessive C polygenic D codominant

B

Which of the following statements is true of the process shown below? A The cells formed at the end of the process contain the same number of chromosomes as the original cells B The cells formed at the end of the process only have half of the chromosomes as the original cells C The cells formed at the end of the process are identical to the original cells D The cells formed at the end of the process do not contain any of the genetic material from the original cells.

B

A DNA molecule is show above. The shape of this molecule can best be described as A a concave disc B an elongaged sphere C a double helix D a linear strand

C

Abigail is thirty-five years old. She is overweight and does not like to exercise. Both of her parents developed diabetes when they were in their forties. When Abigail visits her doctor, she learns that she is at risk for diabetes. What might her doctor recommend to help reduce her risk for developing diabetes? I.eating lots of carbohydrates and sugars II.losing weight III.exercising at least 3 times a week A I and II only B I, II, and III C II and III only D I and III only

C

Dr. Stevens is examining the DNA sequences of a group of mice. He notices that in one of the mice, one nucleotide pair is substituted with another in the part of the DNA sequence that codes for fur color. However, despite the substitution, the mouse still has the same fur color as the other mice with the correct DNA sequence. Why doesn't the substitution of nucleotides in the mouse change its phenotype, or physical characteristics? A The mouse has a completely different DNA sequence than the other mice. B DNA sequences don't determine the color of a mouse's fur. C The substituted nucleotide has the same directions as the original nucleotide. D Substitutions in the nucleotides of a mouse's DNA never affect their phenotypes.

C

Every trait you see on an organism is a result of that organism's DNA instructing the organism's cells. How does the information stored in DNA's nucleotides translate into traits such as eye color and ear shape? A Traits are determined by a group of enzymes known as DNA helicases. B Traits are determined by the presence or absence of lac operons along a series of nucleotides C Traits are determined by proteins that are built according to the instructions stored in genes. D Traits are determined by codons that are stored in groups of nucleotides

C

In the DNA strand below, two nucleotides were reversed during replication. What will happen when the replicated DNA strand is translated into proteins? A The same protein, isoleucine, will be formed. B No proteins will be formed at all. C Tyrosine will be formed instead of isoleucine. D Nothing will happen.

C

The genetic code is a sequence of DNA nucleotides. In eukaryotic cells, the DNA is located in the nuclei of the cells. The genetic code is nearly universal in that A the amino acids are assigned to the same DNA sequences in most living things B the same codons are assigned to the same DNA sequences in most living things C the same codons are assigned to the same amino acids in most living things D none of these are correct

C

The main purpose of DNA is to store information. Where is information stored within a DNA molecule? A in the deoxyribose B in the phosphate groups C in the sequence of nitrogen bases D in a nucleotide

C

The sequence of bases on one strand of a DNA molecule is ATTGCCCATG. What will be the sequence on the complementary strand? A CGGTAAACGT B ATTGCCCATG C TAACGGGTAC D GCCATTTGCA

C

The type of RNA that carries information from DNA to the ribosome of a cell is known as A tRNA B rRNA C mRNA D pRNA

C

A DNA molecule consists of many individual structures that each contain a 5-carbon sugar, a nitrogen-containing base, and a phosphate group. What are these individual structures called? A RNA molecules B nucleic acids C proteins D nucleotides

D

A karyotype is a complete set of chromosomes that constitutes the entire genome of a species. The image above shows the presence of three copies of chromosome 21 in a human's karyotype. Which of the following is definitely true? A This person will have cancer in their lifetime B This person is a female C This person is a male D This person has a chromosomal abnormality

D

A recessive gene located on the X chromosome is the cause of muscular dystrophy in affected individuals. Males are more likely to suffer from muscular dystrophy than females because A muscular distrophy is associated with high testosterone levels. B males have two copies of the X chromosome C females have no copies of the X chromosome D males have only one copy of the X chromosome

D

An organism's phenotype describes a visible trait, such as tall height, brown eyes, or black fur. How does genotypic variation occur? A Genotypic variation only occurs during binary fission B Genotypic variation occurs when alleles are randomly sorted during asexual reproduction C Genotypic variation only occurs when genetic mutations occur D Genotypic variation occurs when alleles are randomly sorted during sexual reproduction

D

Humans possess two alleles, or variations, for each gene. The alleles may be the same, or they may be different. When humans reproduce, their alleles are separated and independently sorted into different gametes, or sex cells. So, when sex cells randomly combine during fertilization to produce offspring, there is A a decreased risk of mutations B a low probability of survival C a high probability of producing a clone D an increase in genetic variation

D

Some genetic mutations occur in the gametes and can be passed on to a person's offspring. Mutations that occur in body cells not involved in reproduction will not be passed on to the person's offspring. However, these mutations can disrupt the control of cell reproduction. Which of the following diseases can result from this type of mutation? A multiple sclerosis B hemophilia C sickle cell anemia D cancer

D

Sometimes, during the process of replication, the DNA code is copied incorrectly, and an incorrect nucleotide is attached to the new strand of DNA. This incorrect copy is known as a A codon B protein C duplicate D mutation

D

The DNA sequences that make up the genetic code of an organism determine which traits the organism will exhibit. How are the instructions coded by DNA translated into an organism's physical traits? A DNA sequences both code genetic instructions within an organism and express an organism's physical traits B Instructions coded by DNA sequences are translated into nucleotides which express an organism's physical traits C DNA sequences that code for genetic instructions attach to phosphate groups that express an organism's physical traits. D Instructions coded by DNA sequences are translated into proteins which express an organism's physical traits

D

The pedigree below shows the inheritance of sickle-cell anemia, an autosomal recessive genetic disease, in a particular family. The shaded symbols represent individuals with sickle-cell anemia. Males are represented with squares and females are represented with circles. Based on this pedigree, what is the probability that the individual indicated by a question mark in the 4th generation would have sickle-cell anemia? A 100% B 75% C 0% D 50%

D

What is the main function of meiosis? A to produce more body cells within an organism B to produce more embryonic cells following fertilization C to produce a clone of an organism in asexual reproduction D to produce gametes for sexual reproduction

D

When a cell needs a particular protein synthesized, messenger RNA (mRNA) is produced from DNA through transcription. How is genetic information "read" from mRNA? A as ribose B as uracil C as codons D as amino acids

D

Which of the following are possible results of exposure to radiation or toxic chemicals? I.DNA mutations occur in body cells and cancer develops. II.DNA mutations occur in body cells and are passed on to offspring. III.The exposed organism becomes sterile. IV.DNA mutations occur in gametes and birth defects result. A II and III only B I and IV only C I, II, and III only D I, III, and IV only

D

Which of the following are involved in RNA translation? I.mRNA II.tRNA III.ribosomes IV.amino acid A I, III, and IV only B I, II, III, and IV C II, III, and IV only D III and IV only

b