Down Syndrome, a congenital genetic disorder in human beings, is cased by : (a) a defective recessive gene in homozygous condition (b) an extra x chromosome (c) trisomy of chromosome 18 (d) trisomy of chromosome 21

Down Syndrome, a congenital genetic disorder in human beings, is cased by : (a) a defective recessive gene in homozygous condition (b) an extra x chromosome (c) trisomy of chromosome 18 (d) trisomy of chromosome 21
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Nondisjunction of a chromosome results in which of the following diagnoses? a) Down Syndrome When a pair of chromosomes fails to separate completely and creates a sperm or oocyte that contains two copies of a particular chromosome (nondisjunction) Down syndrome results from three number 21 chromosomes. b) Huntingon Disease Huntington disease is one example of a germ-line mutation. c) Duchenne Muscular Dystrophy Duchenne muscular dystrophy, an inherited form of muscular dystrophy, is an example of a genetic caused by structural gene mutations. d) Marphan Syndrome Marphan Syndrome is a genetic condition that may occur in a single family member as a result of spontaneous mutation.

Description : Nondisjunction of a chromosome results in which of the following diagnoses? a) Down Syndrome When a pair of chromosomes fails to separate completely and creates a sperm or oocyte that contains two ... genetic condition that may occur in a single family member as a result of spontaneous mutation.

Last Answer : a) Down Syndrome When a pair of chromosomes fails to separate completely and creates a sperm or oocyte that contains two copies of a particular chromosome (nondisjunction) Down syndrome results from three number 21 chromosomes.

Down’s syndrome is caused by an extra copy of chromosome number 21. What percentage of offspring produced by an affected mother and a normal father would be affected by this disorder? (a) 100% (b) 75% (c) 50% (d) 25%

Description : Down’s syndrome is caused by an extra copy of chromosome number 21. What percentage of offspring produced by an affected mother and a normal father would be affected by this disorder? (a) 100% (b) 75% (c) 50% (d) 25%

Last Answer : (c) 50%

Pick out the correct statements. (1) Haemophilia is a sex-linked recessive disease. (2) Down’s syndrome is due to aneuploidy. (3) Phenylketonuria is an autosomal recessive gene disorder. (4) Sickle cell anaemia is an X-linked recessive gene disorder. (a) (1), (3) and (4) are correct. (b) (1), (2) and (3) are correct. (c) (1) and (4) are correct. (d) (2) and (4) are correct.

Description : Pick out the correct statements. (1) Haemophilia is a sex-linked recessive disease. (2) Down's syndrome is due to aneuploidy. (3) Phenylketonuria is an autosomal recessive gene disorder. (4) Sickle cell anaemia is an X- ... are correct. (c) (1) and (4) are correct. (d) (2) and (4) are correct.

Last Answer : (b) (1), (2) and (3) are correct.

Cri-du-chat syndrome in humans is caused by the (a) trisomy of 21st chromosome (b) fertilisation of an XX egg by a normal Y-bearing sperm (c) loss of half of the short arm of chromosome 5 (d) loss of half of the long arm of chromosome 5.

Description : Cri-du-chat syndrome in humans is caused by the (a) trisomy of 21st chromosome (b) fertilisation of an XX egg by a normal Y-bearing sperm (c) loss of half of the short arm of chromosome 5 (d) loss of half of the long arm of chromosome 5.

Last Answer : (c) loss of half of the short arm of chromosome 5

Which type of Mendelian inherited condition results in both genders being affected equally in a vertical pattern? a) Automosomal dominant inheritance An individual who has an autosomal dominant inherited condition carries a gene mutation for that condition on one chromosome of a pair. b) Automosomal recessive inheritance The pattern of inheritance in autosomal recessive inherited conditions is different from that of autosomal dominant inherited conditions in that it is more horizontal than vertical, with relatives of a single generation tending to have the condition. c) X-linked inheritance X-linked conditions may be inherited in families in recessive or dominant patterns.

Description : Which type of Mendelian inherited condition results in both genders being affected equally in a vertical pattern? a) Automosomal dominant inheritance An individual who has an autosomal dominant ... that combine during early embryonic development leading to incomplete closure of the neural tube.

Last Answer : a) Automosomal dominant inheritance An individual who has an autosomal dominant inherited condition carries a gene mutation for that condition on one chromosome of a pair.

.In Drosophila, the XXY condition leads to femaleness whereas in human beings the same condition leads to Klinefelter’s syndrome in male. It proves (a) in human beings Y chromosome is active in sex determination (b) Y chromosome is active in sex determination in both human beings and Drosophila (c) in Drosophila Y chromosome decides femaleness (d) Y chromosome of man have genes for syndrome.

Description : .In Drosophila, the XXY condition leads to femaleness whereas in human beings the same condition leads to Klinefelter's syndrome in male. It proves (a) in human beings Y chromosome is active in ... (c) in Drosophila Y chromosome decides femaleness (d) Y chromosome of man have genes for syndrome.

Last Answer : (a) in human beings Y chromosome is active in sex determination

Trials for gene therapy in human beings were first carried out, with considerable success, in a genetic disease called (A) Cystic fibrosis (B) Thalassemia (C) Adenosine deaminase deficiency (D) Lesch-Nyhan syndrome

Description : Trials for gene therapy in human beings were first carried out, with considerable success, in a genetic disease called (A) Cystic fibrosis (B) Thalassemia (C) Adenosine deaminase deficiency (D) Lesch-Nyhan syndrome

Last Answer : Answer : C

How many chromosomes per cell does a Down's Syndrome (trisomy 21) victim have?

Description : How many chromosomes per cell does a Down's Syndrome (trisomy 21) victim have?

Last Answer : ANSWER: 47

A true breeding plant is (a) one that is able to breed on its own (b) produced due to cross-pollination among unrelated plants (c) near homozygous and produces offspring of its own kind (d) always homozygous recessive in its genetic constitution.

Description : A true breeding plant is (a) one that is able to breed on its own (b) produced due to cross-pollination among unrelated plants (c) near homozygous and produces offspring of its own kind (d) always homozygous recessive in its genetic constitution.

Last Answer : c) near homozygous and produces offspring of its own kind

An abnormal human male phenotype involving an extra X-chromosome (XXY) is a case of (a) Edward’s syndrome (b) Klinefelter’s syndrome (c) intersex (d) Down’s syndrome.

Description : An abnormal human male phenotype involving an extra X-chromosome (XXY) is a case of (a) Edward’s syndrome (b) Klinefelter’s syndrome (c) intersex (d) Down’s syndrome.

Last Answer : (b) Klinefelter’s syndrome

Which of the following most appropriately describes haemophilia? (a) Chromosomal disorder (b) Dominant gene disorder (c) Recessive gene disorder (d) X-linked recessive gene disorder

Description : Which of the following most appropriately describes haemophilia? (a) Chromosomal disorder (b) Dominant gene disorder (c) Recessive gene disorder (d) X-linked recessive gene disorder

Last Answer : (d) X-linked recessive gene disorder

A gene showing co-dominance has (a) alleles that are recessive to each other (b) both alleles independently expressed in the heterozygote (c) one allele dominant on the other (d) alleles tightly linked on the same chromosome.

Description : A gene showing co-dominance has (a) alleles that are recessive to each other (b) both alleles independently expressed in the heterozygote (c) one allele dominant on the other (d) alleles tightly linked on the same chromosome.

Last Answer : (b) both alleles independently expressed in the heterozygote

Mongolian Idiocy due to trisomy in 21st chromsome is called (a) Down’s syndrome (b) Turner’s syndrome (c) Klinefelter’s syndrome (d) Triple X syndrome

Description : Mongolian Idiocy due to trisomy in 21st chromsome is called (a) Down’s syndrome (b) Turner’s syndrome (c) Klinefelter’s syndrome (d) Triple X syndrome

Last Answer : (a) Down’s syndrome

Which one of the following conditions correctly describes the manner of determining the sex? (a) Homozygous sex chromosomes (ZZ) determine female sex in birds. (b) XO type of sex chromosomes determine male sex in grasshopper. (c) XO condition in humans as found in Turner’s syndrome, determines female sex. (d) Homozygous sex chromosomes (XX) produce male in Drosophila.

Description : Which one of the following conditions correctly describes the manner of determining the sex? (a) Homozygous sex chromosomes (ZZ) determine female sex in birds. (b) XO type of sex chromosomes ... s syndrome, determines female sex. (d) Homozygous sex chromosomes (XX) produce male in Drosophila.

Last Answer : (b) XO type of sex chromosomes determine male sex in grasshopper.

A gene is said to be dominant if (a) it expresses its effect only in homozygous state (b) it expresses its effect only in heterozygous condition (c) it expresses its effect both in homozygous and heterozygous condition (d) it never expresses its effect in any condition.

Description : A gene is said to be dominant if (a) it expresses its effect only in homozygous state (b) it expresses its effect only in heterozygous condition (c) it expresses its effect both in homozygous and heterozygous condition (d) it never expresses its effect in any condition.

Last Answer : (c) it expresses its effect both in homozygous and

Lesch-Nyhan syndrome, the sex linked recessive disorder is due to the lack of the enzyme: (A) Hypoxanthine-guanine phosphoribosyl transferse (B) Xanthine oxidase (C) Adenine phosphoribosyl transferase (D) Adenosine deaminase

Description : Lesch-Nyhan syndrome, the sex linked recessive disorder is due to the lack of the enzyme: (A) Hypoxanthine-guanine phosphoribosyl transferse (B) Xanthine oxidase (C) Adenine phosphoribosyl transferase (D) Adenosine deaminase

Last Answer : Answer : A

Production of a human protein in bacteria by genetic engineering is possible because (a) the human chromosome can replicate in bacterial cell (b) the mechanism of gene regulation is identical in humans and bacteria (c) bacterial cell can carry out the RNA splicing reactions (d) the genetic code is universal.

Description : Production of a human protein in bacteria by genetic engineering is possible because (a) the human chromosome can replicate in bacterial cell (b) the mechanism of gene regulation is identical in ... ) bacterial cell can carry out the RNA splicing reactions (d) the genetic code is universal.

Last Answer : (d) the genetic code is universal.

What is a recessive lethal genetic disorder?

Description : What is a recessive lethal genetic disorder?

Last Answer : Feel Free to Answer

.In which of the following diseases, the man has an extra X-chromosome? (a) Turner’s syndrome (b) Klinefelter’s syndrome (c) Down’s syndrome (d) Haemophilia

Description : .In which of the following diseases, the man has an extra X-chromosome? (a) Turner’s syndrome (b) Klinefelter’s syndrome (c) Down’s syndrome (d) Haemophilia

Last Answer : (b) Klinefelter’s syndrome

F1 x homozygous recessive parent

Description : F1 x homozygous recessive parent

Last Answer : Ans. Test Cross

All are true about lesch-nyhan syndrome except (A) Produces self-mutilation (B) Genetic deficiency of the enzyme (C) Elevated levels of uric acid in blood (D) Inheritance is autosomal recessive

Description : All are true about lesch-nyhan syndrome except (A) Produces self-mutilation (B) Genetic deficiency of the enzyme (C) Elevated levels of uric acid in blood (D) Inheritance is autosomal recessive

Last Answer : Answer : B

.Down’s syndrome in humans is due to (a) three ‘X’ chromosomes (b) three copies of chromosome 21 (c) monosomy (d) two ‘Y’ chromosomes.

Description : .Down’s syndrome in humans is due to (a) three ‘X’ chromosomes (b) three copies of chromosome 21 (c) monosomy (d) two ‘Y’ chromosomes.

Last Answer : b) three copies of chromosome 21

What is defective development or congenital absence of an organ or tissue called?

Description : What is defective development or congenital absence of an organ or tissue called?

Last Answer : Need answer

What protein deos trisomy 21 code for?

Description : What protein deos trisomy 21 code for?

Last Answer : Feel Free to Answer

The human insulin gene located on the short arm of chromosome: (A) 11 (B) 17 (C) 18 (D) 20

Description : The human insulin gene located on the short arm of chromosome: (A) 11 (B) 17 (C) 18 (D) 20

Last Answer : Answer : A

Why is a homozygous recessive used in a testcross? -Biology

Description : Why is a homozygous recessive used in a testcross? -Biology

Last Answer : answer:

When crossing a homozygous recessive with a heterozygote? -Biology

Description : When crossing a homozygous recessive with a heterozygote? -Biology

Last Answer : answer:

If a homozygous dominant parent and a heterozygous parent are crossed what percentage of the offspring are expected to be homozygous recessive?

Description : If a homozygous dominant parent and a heterozygous parent are crossed what percentage of the offspring are expected to be homozygous recessive?

Last Answer : Rr

A cross between homozygous recessive and heterozygous plant is - (1) Back cross (2) Test cross (3) Monohybrid cross (4) Dihybrid cross

Description : A cross between homozygous recessive and heterozygous plant is - (1) Back cross (2) Test cross (3) Monohybrid cross (4) Dihybrid cross

Last Answer : (2) Test cross Explanation: A cross between homozygous recessive and heterozygous plant is called Test Cross

4. Crossing a Dominant character with (Homozygous & Hetrozygous) with a recessive trait to know the genome is called;- a) Back cross b) Monohybrid Cross C) Test Cross d)Dihybrid Cross

Description : 4. Crossing a Dominant character with (Homozygous & Hetrozygous) with a recessive trait to know the genome is called;- a) Back cross b) Monohybrid Cross C) Test Cross d)Dihybrid Cross

Last Answer : C) Test Cross

5 Consider a cross in which a trait is inherited by incomplete dominance. What percentage of the F2 from the matng of homozygous dominant and homozygous recessive individuals will possess the dominant phenotype?

Description : 5 Consider a cross in which a trait is inherited by incomplete dominance. What percentage of the F2 from the matng of homozygous dominant and homozygous recessive individuals will possess the dominant phenotype? a) 0 per cent b) 25 per cent c) 50 per cent d) 75 per cent

Last Answer : ANS: b 25 per cent

A cross between homozygous recessive and heterozygous plant is (1) Back cross (2) Test cross (3) Monohybrid cross (4) Dihybrid cross

Description : A cross between homozygous recessive and heterozygous plant is (1) Back cross (2) Test cross (3) Monohybrid cross (4) Dihybrid cross

Last Answer : Test cross

.Identify the correct order of organisation of genetic material from largest to smallest. (a) Genome, chromosome, gene, nucleotide (b) Chromosome, genome, nucleotide, gene (c) Chromosome, gene, genome, nucleotide (d) Genome, chromosome, nucleotide, gene (

Description : .Identify the correct order of organisation of genetic material from largest to smallest. (a) Genome, chromosome, gene, nucleotide (b) Chromosome, genome, nucleotide, gene (c) Chromosome, gene, genome, nucleotide (d) Genome, chromosome, nucleotide, gene (

Last Answer : (a) Genome, chromosome, gene, nucleotide

This female American geneticist achieved recognition as one of the world's foremost investigators in cytogenetics, the study of heredity by cellular and genetic methods. In 1951 she discovered that gene fragments in corn could move from chromosome to chromosome, and even from cell to cell. Thirty-two years after this extraordinary work, she was awarded the Nobel Prize in medicine in 1983. Who is this notable woman scientist?

Description : This female American geneticist achieved recognition as one of the world's foremost investigators in cytogenetics, the study of heredity by cellular and genetic methods. In 1951 she discovered that gene ... was awarded the Nobel Prize in medicine in 1983. Who is this notable woman scientist?

Last Answer : ANSWER: (BARBARW) McCLINTOCK

A woman with 47 chromosomes due to three copies of chromosome 21 is characterised by (a) superfemaleness (b) triploidy (c) Turner’s syndrome (d) Down’s syndrome.

Description : A woman with 47 chromosomes due to three copies of chromosome 21 is characterised by (a) superfemaleness (b) triploidy (c) Turner’s syndrome (d) Down’s syndrome.

Last Answer : (d) Down’s syndrome.

Which of the statements listed below about bleeding disorders is/are correct? A. Acquired bleeding disorders are more common than congenital defects. B. Deficiencies of vitamin K decrease production of factors II, VII, IX, and X, protein C, and protein S. C. Hypothermia below 32؛C rarely causes a bleeding disorder. D. Von Willebrand's disease is a very uncommon congenital bleeding disorder.

Description : Which of the statements listed below about bleeding disorders is/are correct? A. Acquired bleeding disorders are more common than congenital defects. B. Deficiencies of vitamin K decrease production ... disorder. D. Von Willebrand's disease is a very uncommon congenital bleeding disorder.

Last Answer : Answer: AB DISCUSSION: Acquired bleeding disorders are significantly more common than congenital bleeding defects. Vitamin K deficiency may be related to malnutrition or competitive inhibition ... a relatively common disorder of bleeding and is generally undetectable by routine screening methods

Anaphase Promoting Complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cell. If APC is defective in a human cell, which of the following is expected to occur? (a) Chromosomes will be fragmented. (b) Chromosomes will not segregate. (c) Recombination of chromosome arms will occur. (d) Chromosomes will not condense

Description : Anaphase Promoting Complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cell. If APC is defective in a human cell, which of the following is expected to ... will not segregate. (c) Recombination of chromosome arms will occur. (d) Chromosomes will not condense

Last Answer : (b) Chromosomes will not segregate.

Anaphase Promoting Complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cells. If APC is defective in a human cell, which of the following is expected to occur ? (1) Chromosomes will be fragmented (2) Chromosomes will not segregate (3) Recombination of chromosome arms will occur (4) Chromosomes will not condense

Description : Anaphase Promoting Complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cells. If APC is defective in a human cell, which of the following is expected to occur ... will not segregate (3) Recombination of chromosome arms will occur (4) Chromosomes will not condense

Last Answer : (2) Chromosomes will not segregate

What is the genetic disorder in which an individual has an overall masculine development, gynaecomastia and is sterile? (a) Down’s syndrome (b) Turner’s syndrome (c) Klinefelter’s syndrome (d) Edward syndrome

Description : What is the genetic disorder in which an individual has an overall masculine development, gynaecomastia and is sterile? (a) Down’s syndrome (b) Turner’s syndrome (c) Klinefelter’s syndrome (d) Edward syndrome

Last Answer : Klinefelter’s syndrome

Which of the following genetic disorders in man are caused by a dominant gene? 1. Edwards Syndrome 2. Huntington's disease 3. Marfan Syndrome 4. Thalassemia Select the correct answer using codes given below: (a) 1 and 3 (b) 1 and 4 (c) 2 and 3 (d) 2 and 4

Description : Which of the following genetic disorders in man are caused by a dominant gene? 1. Edwards Syndrome 2. Huntington's disease 3. Marfan Syndrome 4. Thalassemia Select the correct answer using codes given below: (a) 1 and 3 (b) 1 and 4 (c) 2 and 3 (d) 2 and 4

Last Answer : Ans:(c)

Haemophilia is more common in males because it is a (a) recessive character carried by Y-chromosome (b) dominant character carried by Y-chromosome (c) dominant trait carried by X-chromosome (d) recessive trait carried by X-chromosome.

Description : Haemophilia is more common in males because it is a (a) recessive character carried by Y-chromosome (b) dominant character carried by Y-chromosome (c) dominant trait carried by X-chromosome (d) recessive trait carried by X-chromosome.

Last Answer : (d) recessive trait carried by X-chromosome

The recessive genes located on X-chromosome humans are always (a) lethal (b) sub-lethal (c) expressed in males (d) expressed in females.

Description : The recessive genes located on X-chromosome humans are always (a) lethal (b) sub-lethal (c) expressed in males (d) expressed in females.

Last Answer : (c) expressed in males

Select the correct match. (a) Haemophilia – Y linked (b) Phenylketonuria – Autosomal dominant trait(c) Sickle cell anaemia – Autosomal recessive trait,chromosome -11 (d) Thalassemia – X linked

Description : Select the correct match. (a) Haemophilia – Y linked (b) Phenylketonuria – Autosomal dominant trait (c) Sickle cell anaemia – Autosomal recessive trait,chromosome -11 (d) Thalassemia – X linked

Last Answer : (c) Sickle cell anaemia – Autosomal recessive trait,chromosome -11

Von Willebrand’s disease is a common, congenital bleeding disorder. Which of the following statement(s) is/are true concerning Von Willebrand’s disease? a. As in hemophilia, it is much more common in men b. A history of spontaneous bleeding is common c. Screening laboratory tests will include a prolonged aPTT with a normal prothrombin time d. Pre-treatment for elective surgery require administration of cryoprecipitate to achieve levels of 23–50% of normal

Description : Von Willebrand's disease is a common, congenital bleeding disorder. Which of the following statement(s) is/are true concerning Von Willebrand's disease? a. As in hemophilia, it is ... -treatment for elective surgery require administration of cryoprecipitate to achieve levels of 23-50% of normal

Last Answer : Answer: c, d Von Willebrand's factor is an adhesive protein that mediates platelet adhesion to collagen. In addition, it protects and prevents the rapid removal of factor VIII ... platelet aggregation responses to ristocetin. The most reliable source of Von Willebrand's factor is cryoprecipitate

Berry aneurysm: a. is a congenital disorder. b. is found most commonly in the posterior portion of the circle of Willis. c. is symptomatic in majority of patients. d. has absent intima elastica

Description : Berry aneurysm: a. is a congenital disorder. b. is found most commonly in the posterior portion of the circle of Willis. c. is symptomatic in majority of patients. d. has absent intima elastica

Last Answer : is a congenital disorder

Albinism is a congenital disorder resulting from the lack of which enzyme? (a) Tyrosinase (b) Xanthine oxidase (c) Catalase (d) Fructokinase

Description : Albinism is a congenital disorder resulting from the lack of which enzyme? (a) Tyrosinase (b) Xanthine oxidase (c) Catalase (d) Fructokinase

Last Answer : (a) Tyrosinase

Congenital nephrotic syndrome?

Description : Congenital nephrotic syndrome?

Last Answer : DefinitionCongenital nephrotic syndrome is disorder passed down through families in which a baby develops protein in the urine and swelling of the body. Congenital means it is present from ... birth weightPoor appetiteSwelling (total body)Signs and testsAn ultrasound done on the pregnant mothe

Which of the following may be responsible for a hypokalaemic hypertension 1) Non-classical congenital adrenal hyperplasia 2) Barter's syndrome 3) Diabetic nephropathy 4) Liddle's syndrome 5) Type IV renal tubular acidosis

Description : Which of the following may be responsible for a hypokalaemic hypertension 1) Non-classical congenital adrenal hyperplasia 2) Barter's syndrome 3) Diabetic nephropathy 4) Liddle's syndrome 5) Type IV renal tubular acidosis

Last Answer : Answers-4 Liddle's syndrome is typically asscoiated with hypokalaemic hypertension and low renin and aldosterone concentrations - the so called pseudo-hyperaldosteronism. Barter's syndrome is associated ... , which may also be produced with diabetic nephropathy. Hence hyperkalaemia is more typical.

.A human female with Turner’s syndrome (a) has 45 chromosomes with XO (b) has one additional X chromosome (c) exhibits male characters (d) is able to produce children with normal husband.

Description : .A human female with Turner’s syndrome (a) has 45 chromosomes with XO (b) has one additional X chromosome (c) exhibits male characters (d) is able to produce children with normal husband.

Last Answer : (a) has 45 chromosomes with XO

Homozygous refers to: a) similar types of chromosomes b) having similar functions on an evolutionary basis c) particles in solution that are inseparable d) having identical alleles for a given gene

Description : Homozygous refers to: a) similar types of chromosomes b) having similar functions on an evolutionary basis c) particles in solution that are inseparable d) having identical alleles for a given gene

Last Answer : ANSWER: D -- HAVING IDENTICAL ALLELES FOR A GIVEN GENE