TEST 12 Flashcards by Aamna Qandil

The biosynthesis of nucleic acids occurs in the:
a) Cytoplasm
b) Mitochondria
c) Nucleus
d) Golgi apparatus

Nucleus

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The building blocks of nucleic acids are called:
a) Amino acids
b) Monosaccharides
c) Nucleotides
d) Fatty acids

Nucleotides

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Which enzyme is responsible for the synthesis of RNA from a DNA template?
a) DNA polymerase
b) RNA polymerase
c) Ligase
d) Helicase

RNA polymerase

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The process of joining nucleotides to form a new DNA strand is known as:
a) Transcription
b) Translation
c) Replication
d) Translocation

Replication

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Which of the following nitrogenous bases is found in RNA but not in DNA?
a) Adenine
b) Thymine
c) Uracil
d) Guanine

Uracil

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The synthesis of RNA using a DNA template is called:
a) DNA replication
b) Transcription
c) Translation
d) Reverse transcription

Transcription

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The enzyme responsible for adding nucleotides during DNA replication is:
a) DNA polymerase
b) RNA polymerase
c) Ligase
d) Helicase

DNA polymerase

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The process by which the genetic information in mRNA is used to build a protein is called:
a) DNA replication
b) Transcription
c) Translation
d) Reverse transcription

Translation

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The synthesis of RNA from RNA is called:
a) DNA replication
b) Transcription
c) Translation
d) Reverse transcription

Transcription

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The nitrogenous base pairs in DNA are held together by:
a) Covalent bonds
b) Hydrogen bonds
c) Ionic bonds
d) Peptide bonds

Hydrogen bonds

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The enzyme responsible for unwinding the DNA double helix during replication is:
a) DNA polymerase
b) RNA polymerase
c) Ligase
d) Helicase

Helicase

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Which of the following is not a component of a nucleotide?
a) Phosphate group
b) Sugar
c) Amino group
d) Nitrogenous base

Amino group

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The enzyme responsible for joining Okazaki fragments during DNA replication is:
a) DNA polymerase
b) RNA polymerase
c) Ligase
d) Helicase

Ligase

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The direction of DNA replication is:
a) 5’ to 3’
b) 3’ to 5’
c) Random
d) Bidirectional

5’ to 3’

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Which nucleotide base pairs with adenine in RNA?
a) Thymine
b) Uracil
c) Cytosine
d) Guanine

Uracil

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The sugar component in DNA nucleotides is ___________.

deoxyribose

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De novo synthesis of purines occurs primarily in the:
a) Nucleus
b) Cytoplasm
c) Endoplasmic reticulum
d) Golgi apparatus

Cytoplasm

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The salvage pathway for purine synthesis involves:
a) Synthesizing purines from scratch
b) Recycling purine bases from nucleotide breakdown
c) Breaking down purines into their constituent bases
d) Importing purines from the extracellular environment

Recycling purine bases from nucleotide breakdown

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Gout is a form of arthritis caused by the accumulation of:
a) Uric acid
b) Adenosine
c) Guanine
d) Thymine

Uric acid

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The enzyme responsible for converting hypoxanthine to xanthine in purine catabolism is:
a) Xanthine oxidase
b) Adenosine deaminase
c) Guanosine kinase
d) Hypoxanthine phosphoribosyltransferase

Xanthine oxidase

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SCID (Severe Combined Immunodeficiency) caused by impaired purine salvage pathway is associated with a deficiency in the enzyme:
a) Adenosine deaminase
b) Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)
c) Xanthine oxidase
d) Guanosine kinase

Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)

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The accumulation of uric acid crystals in the joints is a characteristic feature of:
a) Gout
b) Leukemia
c) Diabetes mellitus
d) Sickle cell anemia

Gout

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The salvage pathway for purine synthesis helps conserve:
a) Energy
b) Nucleotide precursors
c) Enzymes
d) Ribosomes

Nucleotide precursors

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In the salvage pathway, the enzyme HGPRT is responsible for:
a) Converting guanine to xanthine
b) Converting adenine to hypoxanthine
c) Converting hypoxanthine to adenosine
d) Converting xanthine to uric acid

Converting adenine to hypoxanthine

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SCID caused by impaired purine salvage pathway is also known as ___________ deficiency.

Lesch-Nyhan

The key enzyme in the de novo synthesis of purines is ___________.

PRPP amidotransferase

Translation is the process of synthesizing ___________ from ___________. a) RNA, DNA b) Proteins, RNA c) RNA, proteins d) DNA, proteins

RNA, proteins

The process of translation occurs in the: a) Nucleus b) Cytoplasm c) Endoplasmic reticulum d) Mitochondria

Cytoplasm

The initiation of translation requires the interaction between the ___________ and the ___________. a) mRNA, ribosome b) tRNA, ribosome c) mRNA, tRNA d) tRNA, mRNA

mRNA, ribosome

The start codon that initiates translation is: a) AUG b) UAG c) UGA d) UAA

AUG

The codon that signals the termination of translation is: a) AUG b) UAG c) UGA d) UAA

UAG

The enzyme responsible for bringing the correct amino acids to the ribosome during translation is called: a) RNA polymerase b) DNA polymerase c) tRNA synthetase d) DNA helicase

tRNA synthetase

The step of translation where the amino acids are linked together to form a polypeptide chain is called: a) Initiation b) Elongation c) Termination d) Transcription

Elongation

The process of translation is assisted by a complex called the ___________. a) Ribosome b) Nucleosome c) Lysosome d) Peroxisome

Ribosome

During translation, the ribosome moves along the mRNA in the ___________ direction. a) 5' to 3' b) 3' to 5' c) Random d) Bidirectional

5' to 3'

Which of the following is not involved in translation? a) mRNA b) rRNA c) tRNA d) DNA polymerase

DNA polymerase

The enzyme responsible for unwinding the DNA double helix during transcription is: a) DNA polymerase b) RNA polymerase c) DNA helicase d) RNA helicase

DNA helicase

The process of translation is divided into three main stages, which are: a) Initiation, transcription, termination b) Initiation, elongation, termination c) Transcription, elongation, termination d) Transcription, translation, termination

Initiation, elongation, termination

The ribosome has two subunits, namely: a) Large and small b) Big and small c) Heavy and light d) Long and short

Large and small

The enzyme responsible for adding amino acids to the growing polypeptide chain during translation is called: a) DNA polymerase b) RNA polymerase c) Ligase d) Peptidyl transferase

Peptidyl transferase

SCID caused by impaired purine salvage pathway is also known as ___________ deficiency.

Lesch-Nyhan

The termination codon in mRNA is recognized by a protein called a: a) Release factor b) Initiator factor c) Elongation factor d) Ribosomal subunit

Release factor

The process of translation begins with the binding of the small ribosomal subunit to the ___________ of mRNA.

start codon

During translation, each amino acid is specified by a three-nucleotide sequence called a ___________.

codon

The codon AUG codes for the amino acid ___________.

methionine

The binding site for the incoming aminoacyl-tRNA during translation is called the ___________ site.

A-site

The enzyme responsible for translocating the ribosome along the mRNA during translation is called ___________.

elongation factor

The process of translation occurs in the nucleus. True or False?

False

The initiation of translation requires the presence of a specific start codon. True or False?

True

The ribosome moves along the mRNA in the 3' to 5' direction during translation. True or False?

False

Antibiotics such as tetracycline and erythromycin can inhibit translation by binding to the ribosome and interfering with protein synthesis. True or False?

True

Protein breakdown is an essential process for recycling amino acids and maintaining cellular homeostasis. True or False?

True

The enzyme responsible for breaking down proteins into amino acids is called protease. True or False?

True

Translation occurs in the cytoplasm of both prokaryotic and eukaryotic cells. True or False?

True

The termination of translation occurs when a stop codon is encountered by the ribosome. True or False?

True

The ribosome is composed of rRNA and proteins. True or False?

True

During translation, the growing polypeptide chain is synthesized from the N-terminus to the C-terminus. True or False?

True

The release factor recognizes the termination codon and releases the completed polypeptide chain from the ribosome. True or False?

True

Translation is a highly regulated process that can be influenced by various cellular factors and signals. True or False?

True

Protein synthesis can be inhibited by antibiotics that target the ribosome, such as chloramphenicol and streptomycin. True or False?

True

Protein breakdown primarily occurs in the nucleus of cells. True or False?

False

The process of translation involves the decoding of the genetic information encoded in the mRNA into a specific sequence of amino acids. True or False?

True

Which type of RNA carries the genetic information from DNA to the ribosome for protein synthesis? a) mRNA b) tRNA c) rRNA d) snRNA

mRNA

The typical structure of tRNA includes a region called the ___________ that binds to the corresponding codon on the mRNA during translation. a) Anticodon b) Promoter c) Terminator d) Exon

Anticodon

rRNA (ribosomal RNA) is a component of: a) mRNA b) tRNA c) Ribosomes d) Nucleosomes

Ribosomes

Exons are the coding regions of genes that: a) Are spliced out during RNA processing b) Are involved in the initiation of transcription c) Carry genetic information to the ribosomes d) Encode amino acid sequences in proteins

Encode amino acid sequences in proteins

Introns are the non-coding regions of genes that: a) Are spliced out during RNA processing b) Are involved in the initiation of transcription c) Carry genetic information to the ribosomes d) Encode amino acid sequences in proteins

Are spliced out during RNA processing

Transcription is the process of synthesizing ___________ from a DNA template. a) DNA b) mRNA c) tRNA d) rRNA

mRNA

The enzyme responsible for synthesizing RNA from a DNA template during transcription is called: a) DNA polymerase b) RNA polymerase c) Ligase d) Helicase

RNA polymerase

The first step of transcription is called: a) Initiation b) Elongation c) Termination d) Translation

Initiation

During initiation of transcription, RNA polymerase binds to a specific DNA sequence called the ___________. a) Promoter b) Terminator c) Codon d) Anticodon

Promoter

The process of transcription continues until the RNA polymerase reaches a specific DNA sequence called the ___________. a) Promoter b) Terminator c) Codon d) Anticodon

Terminator

The process of transcription occurs in the ___________ of eukaryotic cells. a) Nucleus b) Cytoplasm c) Mitochondria d) Endoplasmic reticulum

Nucleus

Amanitin is a toxic substance found in certain mushrooms that inhibits ___________ during transcription. a) DNA polymerase b) RNA polymerase c) Ligase d) Helicase

RNA polymerase

tRNA carries amino acids to the ribosome during translation. True or False?

True

rRNA forms the structural components of ribosomes. True or False?

True

Exons are removed from the pre-mRNA during RNA processing. True or False?

False

Introns are retained in the mature mRNA and contribute to protein coding. True or False?

False

Transcription occurs in the 3' to 5' direction on the DNA template strand. True or False?

False

The promoter region of a gene is involved in the initiation of transcription. True or False?

True

Transcription is the process of synthesizing DNA from an RNA template. True or False?

False

The termination of transcription is signaled by the presence of a terminator sequence on the DNA template strand. True or False?

True

tRNA carries amino acids to the ribosome based on the ___________ sequence on the mRNA.

codon

mRNA is synthesized during the process of ___________.

transcription

In eukaryotic cells, transcription occurs in the ___________.

nucleus

During initiation of transcription, RNA polymerase binds to the DNA at the ___________ region.

promoter

The process of removing introns and joining exons in pre-mRNA is called ___________.

splicing

Amanitin poisoning can lead to liver failure and death. True or False?

True

Amanitin inhibits RNA polymerase, preventing transcription. True or False?

True

mRNA undergoes processing, including capping, splicing, and polyadenylation, to produce mature mRNA. True or False?

True

Intron sequences are important for regulating gene expression. True or False?

False

DNA stands for: a) Deoxyribonucleic acid b) Ribonucleic acid c) Deoxyribose nucleic acid d) Ribose nucleic acid

Deoxyribonucleic acid

The structure of DNA is a: a) Double-stranded helix b) Single-stranded helix c) Triple-stranded helix d) Quadruple-stranded helix

Double-stranded helix

The two strands of DNA are held together by: a) Hydrogen bonds b) Covalent bonds c) Ionic bonds d) Peptide bonds

Hydrogen bonds

Telomeres are located at the: a) Start of a DNA strand b) End of a DNA strand c) Middle of a DNA strand d) Both ends and middle of a DNA strand

End of a DNA strand

DNA replication starts at specific sites called: a) Promoters b) Termination sites c) Telomeres d) Origins of replication

Origins of replication

Deamination is a type of DNA damage that involves the: a) Addition of a chemical group to a nucleotide b) Loss of a chemical group from a nucleotide c) Conversion of a cytosine to uracil d) Formation of covalent bonds between adjacent nucleotides

Conversion of a cytosine to uracil

Depurination is a type of DNA damage that involves the: a) Addition of a chemical group to a nucleotide b) Loss of a chemical group from a nucleotide c) Conversion of a cytosine to uracil d) Loss of a purine base from a nucleotide

Loss of a purine base from a nucleotide

UV light can cause DNA damage by: a) Inducing cross-links between adjacent nucleotides b) Breaking the phosphodiester backbone of DNA c) Forming thymine dimers d) Altering the sugar-phosphate backbone of DNA

Forming thymine dimers

Double-strand breakage of DNA can occur due to: a) Deamination b) Depurination c) UV light exposure d) Ionizing radiation

Ionizing radiation

Oxidative stress can lead to DNA damage by: a) Causing thymine dimers b) Inducing single-strand breaks in DNA c) Forming cross-links between DNA strands d) Alkylating DNA bases

Inducing single-strand breaks in DNA

The process of DNA repair that involves the removal of damaged bases by specific enzymes is called: a) Base excision repair b) Nucleotide excision repair c) Mismatch repair d) Homologous recombination

Base excision repair

Mismatch repair is a DNA repair mechanism that corrects errors in DNA replication by: a) Replacing damaged bases with new ones b) Removing and replacing mismatched nucleotides c) Repairing double-strand breaks d) Rejoining broken DNA strands

Removing and replacing mismatched nucleotides

The "Angelina effect" refers to: a) The effect of UV light exposure on DNA damage b) The impact of mutations in the BRCA genes on breast and ovarian cancer risk c) The role of p53 mutation in DNA repair d) The relationship between Xeroderma pigmentosum and skin cancer

The impact of mutations in the BRCA genes on breast and ovarian cancer risk

Mutations in the BRCA genes are associated with an increased risk of: a) Lung cancer b) Colon cancer c) Breast and ovarian cancer d) Leukemia

Breast and ovarian cancer

Mutations in the p53 gene are associated with an increased risk of: a) Lung cancer b) Colon cancer c) Breast and ovarian cancer d) Various types of cancer

Various types of cancer

Xeroderma pigmentosum is a genetic disorder characterized by: a) Increased sensitivity to UV light and a high risk of skin cancer b) Defective mismatch repair and a high risk of colon cancer c) Impaired DNA replication and a high risk of breast cancer d) Deficiency in telomerase activity and premature aging

Increased sensitivity to UV light and a high risk of skin cancer

DNA consists of four different nucleotide bases: adenine, cytosine, guanine, and uracil. True or False?

False

Each DNA strand has a complementary sequence that is determined by the base-pairing rules (adenine with thymine and cytosine with guanine). True or False?

True

Telomeres play a crucial role in maintaining the stability and integrity of the DNA molecule. True or False?

True

DNA replication is a semiconservative process, meaning that each new DNA molecule contains one original strand and one newly synthesized strand. True or False?

True

Deamination can lead to changes in the DNA sequence and potentially cause mutations. True or False?

True

UV light-induced thymine dimers can disrupt the normal structure of DNA and interfere with DNA replication and transcription. True or False?

True

Double-strand breakage of DNA can be repaired by the process of homologous recombination. True or False?

True

Oxidative stress refers to the imbalance between the production of reactive oxygen species and the ability of the body to detoxify them, leading to DNA damage. True or False?

True

Base excision repair is a DNA repair mechanism that specifically targets and corrects mismatched nucleotides in the DNA sequence. True or False?

False

During transcription, the enzyme ___________ synthesizes RNA from a DNA template.

RNA polymerase

The first step of DNA replication is the unwinding of the double helix by an enzyme called ___________.

helicase

Depurination is the loss of a ___________ base from a DNA nucleotide.

purine

UV light-induced damage in DNA can lead to the formation of ___________ dimers.

thymine

The DNA repair mechanism called ___________ excision repair is involved in removing bulky DNA lesions caused by chemicals and UV light.

nucleotide

The enzyme telomerase can add repetitive DNA sequences to the ends of chromosomes to prevent their shortening during replication. True or False?

True

Deamination is a process that converts adenine to cytosine in DNA. True or False?

False

Double-strand breaks in DNA can be repaired through non-homologous end joining, which often results in the loss of a few nucleotides. True or False?

True

The BRCA1 and BRCA2 genes are involved in the repair of double-strand breaks in DNA. True or False?

True

Xeroderma pigmentosum is an autosomal recessive disorder caused by mutations in genes involved in nucleotide excision repair. True or False?

True

The main function of telomeres is to: a) Encode genetic information b) Protect the ends of chromosomes from degradation and fusion c) Regulate gene expression d) Initiate DNA replication

Protect the ends of chromosomes from degradation and fusion

The enzyme responsible for repairing single-strand breaks in DNA is called: a) DNA polymerase b) DNA ligase c) DNA helicase d) DNA glycosylase

DNA ligase

Deamination is a spontaneous DNA damage process that can occur without the influence of external factors. True or False?

True

The p53 gene is often referred to as the "guardian of the genome" due to its role in regulating cell cycle progression and initiating DNA repair. True or False?

True

Xeroderma pigmentosum is characterized by an increased risk of developing skin cancer upon exposure to UV light. True or False?

True

The central dogma of molecular biology states that information flows from: a) DNA to RNA to protein b) RNA to DNA to protein c) Protein to RNA to DNA d) Protein to DNA to RNA

DNA to RNA to protein

The discovery of the double helix structure of DNA was made by: a) James Watson and Francis Crick b) Rosalind Franklin and Maurice Wilkins c) Linus Pauling d) Oswald Avery, Colin MacLeod, and Maclyn McCarty

James Watson and Francis Crick

The Watson and Crick model of DNA structure proposed that the two strands of DNA are: a) Parallel to each other b) Antiparallel to each other c) Complementary to each other d) Identical to each other

Antiparallel to each other

Mitochondrial DNA is inherited from: a) Both parents b) The mother only c) The father only d) Randomly from either parent

The mother only

Okazaki fragments are short segments of DNA synthesized during: a) DNA replication on the leading strand b) DNA replication on the lagging strand c) Transcription d) Translation

DNA replication on the lagging strand

Circadian clock genes are involved in regulating: a) DNA replication b) DNA repair c) Cellular metabolism d) Biological rhythms and sleep-wake cycles

Biological rhythms and sleep-wake cycles

The discovery of the double helix structure of DNA was based on X-ray crystallography data obtained by Rosalind Franklin. True or False?

True

The Watson and Crick model of DNA structure explained how DNA replicates and transcribes into RNA. True or False?

True

Mitochondrial DNA contains a different set of genes compared to nuclear DNA. True or False?

True

Okazaki fragments are joined together by the enzyme DNA ligase during DNA replication. True or False?

True

Circadian clock genes play a role in regulating various physiological processes, including metabolism, hormone production, and cell cycle progression. True or False?

True

The discovery of the structure of DNA by Watson and Crick was published in the journal ___________ in 1953.

Nature

Mitochondrial DNA is circular and encodes genes necessary for ___________ synthesis.

energy (ATP)

Okazaki fragments are synthesized by the enzyme ___________.

DNA polymerase

Circadian clock genes, such as ___________ and ___________, regulate the timing of biological processes.

Clock, Per

The central dogma of molecular biology states that information flows from RNA to DNA to protein. True or False?

False

Rosalind Franklin's X-ray crystallography images played a crucial role in determining the structure of DNA. True or False?

True

The Watson and Crick model of DNA structure proposed that the two DNA strands run in the same direction. True or False?

False

Mitochondrial DNA is primarily involved in protein synthesis. True or False?

False

Okazaki fragments are only synthesized on the lagging strand during DNA replication. True or False?

True

The enzyme responsible for adding nucleotides during DNA replication is called ___________.

DNA polymerase

Mitochondrial DNA is more susceptible to ___________ damage compared to nuclear DNA.

oxidative

The Okazaki fragments are eventually joined together by the enzyme ___________.

DNA ligase

The ___________ genes regulate the circadian clock and are found in many organisms.

Clock, Period

The central dogma of molecular biology describes the flow of genetic information from DNA to RNA to protein. True or False?

True

The discovery of the double helix structure of DNA was made by Rosalind Franklin. True or False?

False

The Watson and Crick model of DNA structure explained the mechanism of DNA replication. True or False?

True

Mitochondrial DNA is inherited from both parents in a Mendelian manner. True or False?

False

Okazaki fragments are short RNA fragments synthesized during transcription. True or False?

False

The discovery of the structure of DNA was based on X-ray diffraction images of DNA fibers taken by ___________.

Rosalind Franklin

Mitochondrial DNA is maternally inherited due to the presence of ___________ in the sperm.

Ubiquitin

The joining of Okazaki fragments is facilitated by the enzyme ___________.

DNA ligase

Circadian clock genes, such as ___________ and ___________, regulate the body's internal clock and daily rhythms.

Clock, Period

Positive regulation of gene expression refers to: a) Activation of gene expression by transcription factors b) Inhibition of gene expression by transcription factors c) Methylation of DNA to suppress gene expression d) Degradation of mRNA to reduce gene expression

Activation of gene expression by transcription factors

Negative regulation of gene expression refers to: a) Activation of gene expression by transcription factors b) Inhibition of gene expression by transcription factors c) Methylation of DNA to suppress gene expression d) Degradation of mRNA to reduce gene expression

Inhibition of gene expression by transcription factors

The process of gene expression involves: a) DNA replication b) RNA translation c) Protein synthesis d) Transcription and translation

Transcription and translation

Promoters are regions of DNA that: a) Enhance gene expression b) Initiate transcription c) Bind transcription factors d) Control mRNA degradation

Initiate transcription

Enhancers are DNA sequences that: a) Enhance gene expression b) Initiate transcription c) Bind transcription factors d) Control mRNA degradation

Enhance gene expression

Response elements are DNA sequences that: a) Enhance gene expression b) Initiate transcription c) Bind transcription factors d) Control mRNA degradation

Bind transcription factors

Transcription factors are proteins that: a) Enhance gene expression b) Initiate transcription c) Bind DNA sequences d) Control mRNA degradation

Bind DNA sequences

Iron uptake in cells is primarily regulated by a protein called: a) Ferritin b) Transferrin c) Heme d) Iron regulatory protein

Transferrin

Hemochromatosis is a genetic disorder characterized by: a) Iron deficiency b) Excessive iron absorption and deposition in tissues c) Impaired heme synthesis d) Altered iron metabolism

Excessive iron absorption and deposition in tissues

Histone modification refers to: a) Changes in the DNA sequence that affect gene expression b) Chemical modifications to histone proteins that influence chromatin structure and gene expression c) Changes in mRNA stability that regulate gene expression d) Alterations in RNA splicing that affect gene expression

Chemical modifications to histone proteins that influence chromatin structure and gene expression

Positive regulation of gene expression leads to increased transcription and higher levels of gene expression. True or False?

True

Negative regulation of gene expression leads to decreased transcription and lower levels of gene expression. True or False?

True

Promoters are located upstream of the transcription start site and are involved in the initiation of transcription. True or False?

True

Enhancers are DNA sequences that can be located far away from the gene they regulate and can influence gene expression by interacting with promoters. True or False?

True

Response elements are specific DNA sequences that bind to transcription factors and regulate gene expression. True or False?

True

The process of converting DNA into RNA is called ___________.

Transcription

Iron uptake in cells is primarily mediated by the ___________ receptor.

Transferrin

Hemochromatosis is most commonly caused by mutations in the ___________ gene.

HFE

Histone modification can include ___________ of histone proteins, such as acetylation and methylation.

Methylation

RNA interference is a mechanism used by scientists to ___________ specific genes.

Silence or turn off

Positive regulation of gene expression can occur through the binding of activator proteins to enhancer elements. True or False?

True

Negative regulation of gene expression can occur through the binding of repressor proteins to response elements. True or False?

True

Promoters are specific DNA sequences located downstream of the transcription start site. True or False?

False

Enhancers are DNA sequences that can be located far away from the gene they regulate. True or False?

True

Transcription factors are proteins that bind to enhancer elements to activate gene expression. True or False?

True

Transcription factors recognize and bind to specific DNA sequences called ___________.

Response elements

Iron uptake in cells is regulated by the protein ___________, which controls the expression of genes involved in iron transport and storage.

Iron regulatory protein

Hemochromatosis is a genetic disorder characterized by excessive ___________ absorption and deposition in various tissues.

Iron

Histone modification involves the addition or removal of chemical groups, such as ___________ and ___________, which can affect gene expression.

Acetyl, Methylation

RNA interference (RNAi) is a technique used by scientists to ___________ the expression of specific genes.

Silence or suppress

Positive regulation of gene expression leads to increased transcription and higher levels of protein synthesis. True or False?

True

Negative regulation of gene expression leads to decreased transcription and lower levels of protein synthesis. True or False?

True

Promoters are specific DNA sequences that bind transcription factors and initiate the transcription process. True or False?

True

Enhancers are DNA sequences that can influence gene expression even if they are located far away from the gene they regulate. True or False?

True

Transcription factors are proteins that bind to response elements in the DNA and can either enhance or inhibit gene expression. True or False?

True

RNA interference (RNAi) is a mechanism that uses small RNA molecules called ___________ to silence or degrade specific RNA molecules.

Small interfering RNA (siRNA)