W5 Genetics Flashcards
True or False. Mendel’s “Laws of Heredity” include ALL of the following.
- Each characteristic corresponds to a single gene.
- Genes occur in pairs, one on each of a paired set of chromosomes.
- Each parent provides one member of each pair of its genes.
- Individual genes are inherited randomly.
- Some traits or characteristics are “dominant” while others are “recessive.”
True
An individual having two different alleles of a particular gene or genes, considered DOMINANT, giving rise to varying offspring is defined as:
A. Heterozygote
B. Homozygote
A. Heterozygote
A trait is RECESSIVE if it is expressed only when both members of a pair of chromosomes carries its gene, which is considered:
A. Heterozygote
B. Homozygote
B. Homozygote
True or False. Dominance and recessivity are properties of traits, not of genes themselves.
True
There are 6 basic patterns of Mendelian inheritance:
- Autosomal dominant inheritance
- Autosomal recessive inheritance
- X-linked recessive inheritance
- X-linked dominant inheritance
- Y-linked inheritance
- Mitochondrial inheritance
When at least one parent carries the gene for the expressed phenotype, which Mendelian pattern is this considered?
A. Autosomal dominant inheritance
B. Autosomal recessive inheritance
A. Autosomal dominant inheritance
**This form of inheritance affects both sexes equally and the gene may be transmitted by either the mother or the father. The probability that an offspring of an individual with the trait will express the trait is 50%
When both parents carry the gene for the expressed phenotype, this is considered which Mendelian pattern?
A. Autosomal recessive inheritance
B. Autosomal dominant inheritance
A. Autosomal recessive inheritance
**Unless a parent is homozygous for the trait, he or she will not express the phenotype (heterozygotes do not express the phenotype). The probability that an offspring of an individual with the trait will express the trait is 50%.
True or False. X-linked recessive inheritance affects females predominantly?
False.
X-linked recessive inheritance affects MALES predominantly. Parents usually are unaffected (the mother usually is an “asymptomatic” carrier of the affected gene). There is no male-to-male transmission. The probability that a female offspring will express the phenotype is 50% if the father is homozygous for the trait and the mother is heterozygous
True or False. X-linked dominant inheritance affects female offspring more than it affects male offspring because an affected male will always transmit the trait to his daughters but to none of his sons.
True.
The probability of an offspring of an affected female being affected is 50%, regardless of the sex of the child.
True or False. Y-linked inheritance affects only males.
True.
All sons of an affected father are affected
Mitochondrial inheritance comes from?
A. Mother
B. Father
A. Mother
A single nucleotide base substitution in a gene may result in significant phenotypic alteration. This is most concerning when it leads to disease states. This substitution is called?
Single Nucleotide Polymorphisms (SNPs)
____________ are proteins whose function is to bind substrates and catalyze their conversion to reaction products differing from the substrates in chemical structure and composition by reducing the reaction’s required Energy of Activation.
Enzymes
True or False. Enzyme catalysts DO NOT return to their original state when the reaction is completed.
False.
Enzymes are not consumed by the reactions they catalyze and DO return to their original state.
A _____________ is an organic compound required by an enzyme in order for the enzyme to be able to reduce the required Energy of Activation of a reaction.
coenzyme
True or False. A coenzyme participates in the reaction by either transferring to the reactants an electron, reduced proton, phosphate, hydroxyl or methyl group or by accepting such a substance from the reactants, and must be regenerated.
True.
A coenzyme is consumed by the reaction.
A _____________ is a nutrient that is required by an enzyme for full activation of the enzyme.
cofactor.
**Unlike a coenzyme, a cofactor functions as part of the enzyme and is not consumed by the reaction. Examples of common cofactors are zinc, magnesium and copper.
The most important food-borne infectious pathogenic bacteria are?
A. Enterotoxins
B. Botulism
C. Enteropathies
D. Hydrolytic enzymes, hemolytic and leucolytic exotoxins,
dermonecrotic exotoxins, exfoliative exotoxins
E. All of the above
E. All of the above
- *Aeromonas hydrophila, Bacillus cereus (enterotoxins)
- *Brucella species, Campylobacter jejuni, Clostridium botulinum (botulism)
- *Clostridium dificile, Clostridium perfringens, Entamoeba histolytica, Escherichia coli (enteropathies)
- *Listeria monocytogenes, Salmonella species, Shigella species, Staphylococcus aureus (hydrolytic enzymes, hemolytic and leucolytic exotoxins, dermonecrotic exotoxins, exfoliative exotoxins and enterotoxins)
“Holy Fire”, “Alimentary Toxic Aleukia”, and “Yellow Rice Disease” are all food borne illnesses cause by ___________?
Mycotoxins produce by fungi
Sources of contaminating microorganisms include:
A. feces, urine, nasal and throat discharges,
B. surface contamination of the hands or arms of food handlers
C. contaminated soils, mud, surface waters, dust, sea water, marine materials and marine life
D. All of the above
D. All of the above
True or False. To avoid food borne illnesses fruits should be served chilled and not stored at ambient temperatures after their skin is broken.
True
True or False. The Hazard Analysis and Critical Control Points (HACCP) approach differs from traditional approaches to food safety in manufacturing locations by changing the emphasis from LOW-LEVEL surveillance applied throughout the manufacturing process to focus on HIGH-LEVEL
monitoring of food contamination applied at specified points in the manufacturing process.
True.
The HACCP identifies manufacturing processes at which the risk of contamination is greatest. This approach increases the efficiency of resource allocation while maximizing the ability to detect problems
There are ____(#)____ operational principles of HACCP programs.
- conduct a hazard analysis
- identify the critical control points in the process
- establish critical limits for preventative measures at each critical point
- monitor critical control points
- take corrective actions when indicated by monitoring
- keep detailed records
- establish verification (validation) procedures
