Genes And Heredity (Exam Mode) By Rnpedia

Down syndrome is a genetic disorder that is caused by an extra copy of chromosome 21, also known as trisomy 21. This extra genetic material disrupts the normal development and causes the characteristic physical and intellectual disabilities associated with Down syndrome. Therefore, the correct answer is XXI, as it represents the extra copy of chromosome 21 that is present in individuals with Down syndrome.

The process of transforming pyruvate into glucose is known as gluconeogenesis. Gluconeogenesis requires 6 ATP molecules to convert each pyruvate molecule into glucose. This process occurs mainly in the liver and kidneys when glucose levels are low, and it helps maintain a constant supply of glucose in the body.

Pompe's disease is a type II glycogen storage disease. This disease is caused by a deficiency of the enzyme acid alpha-glucosidase, which leads to the accumulation of glycogen in various tissues, particularly in muscles. This accumulation can cause muscle weakness, respiratory problems, and other symptoms associated with Pompe's disease.

The correct answer is AUG. The start codon in most cases is AUG, which codes for the amino acid methionine. It marks the beginning of the protein-coding sequence on the mRNA molecule and is recognized by the ribosome during translation. UAA and UGA are stop codons, indicating the end of the protein-coding sequence, while AGU is a codon for the amino acid serine.

Krabbe's disease is a rare genetic disorder characterized by the destruction of the protective covering of nerve cells in the brain and nervous system. It is inherited in an autosomal recessive manner, meaning that both parents must carry the faulty gene for a child to be affected. Symptoms of Krabbe's disease typically include spasticity (muscle stiffness and tightness) and optic nerve deficits (vision problems). Nausea, however, is not a characteristic symptom of Krabbe's disease.

Creatine is not a derivative of the amino acid Tryptophan. Melatonin, serotonin, and niacin are all derived from Tryptophan through various metabolic pathways. Creatine, on the other hand, is synthesized from the amino acids glycine and arginine in the liver and kidneys, and is not directly derived from Tryptophan.

Cystic fibrosis is a genetic disorder that affects the respiratory and digestive systems. The prevalence ratio represents the number of people with the condition in relation to the general population. In this case, the approximate prevalence ratio for cystic fibrosis is 1:2,000, which means that for every 2,000 people in the general population, one person is affected by cystic fibrosis.

The Southern blot technique is a method used to detect specific DNA sequences in a sample. It involves DNA hybridization, which is the process of forming a stable double-stranded DNA molecule by combining single-stranded DNA with complementary sequences. The technique also utilizes a filter and film combination to capture and visualize the DNA fragments. However, the Southern blot is not activated by antigen/antibody reactions, as this is a characteristic of other techniques such as the Western blot, which is used to detect specific proteins.

A Western blot is a laboratory technique used to detect specific proteins in a sample. It involves the separation of proteins by size using gel electrophoresis, followed by their transfer onto a membrane. The membrane is then incubated with antibodies that specifically bind to the target protein. Antibody/protein hybridization refers to the binding of the antibody to the protein of interest, making it the correct answer. DNA/RNA combination, RNA transcription, and polymerase chain reaction are not characteristics of a Western blot.

The Hardy-Weinberg law states that the frequencies of alleles and genotypes in a population will remain constant from generation to generation in the absence of other influences such as mutation, migration, and natural selection. This means that genotype selection does not occur at the locus, as the law assumes that all genotypes have an equal chance of survival and reproduction.

Hurler's syndrome is a genetic disorder that is inherited in an autosomal recessive manner. It is characterized by delayed mental development, corneal deficits, and other physical abnormalities. However, spasticity is not typically associated with Hurler's syndrome. Spasticity refers to muscle stiffness and tightness, which is not a common feature of this condition.

Fabry's disease is an X-linked disease characterized by low levels of alpha-galactosidase A enzyme, which leads to the accumulation of ceramide trihexoside in various tissues. This accumulation can cause symptoms such as skin rashes, kidney problems, heart complications, and pain in the extremities. However, profound muscular weakness is not a characteristic of Fabry's disease.

S-adenosyl-methionine (SAM) is a molecule that aids in the transfer of methyl groups. It is formed from the combination of methionine and ATP. SAM is not considered a rate limiting enzyme of glycolysis, as rate limiting enzymes are the enzymes that regulate the overall rate of a metabolic pathway. SAM's main function is to donate methyl groups for various biochemical reactions in the body.

tRNA, or transfer RNA, is the smallest type of RNA. It is responsible for carrying amino acids to the ribosome during protein synthesis. tRNA molecules are typically around 70-90 nucleotides long, making them smaller than mRNA (which can be hundreds to thousands of nucleotides long) and rRNA (which can be thousands to tens of thousands of nucleotides long).

The correct answer is C-G. In DNA, the nucleotide cytosine always pairs with the nucleotide guanine. This pairing is based on the complementary base pairing rule, where cytosine forms three hydrogen bonds with guanine. Therefore, C-G is the correct pairing.

Autosomal dominant inheritance means that if one parent has the gene mutation, there is a 50% chance of passing it on to each child. However, sickle cell anemia is not inherited in this manner. It is an autosomal recessive disorder, meaning that both parents must carry the gene mutation for a child to inherit the condition. Therefore, autosomal dominant is not a characteristic of sickle cell anemia.

The TCA cycle, also known as the citric acid cycle or Krebs cycle, is a series of chemical reactions that occur in the mitochondria of cells. During this cycle, one molecule of glucose is broken down to produce energy in the form of ATP. One of the byproducts of the TCA cycle is NADH, which is an energy-rich molecule that carries electrons to the electron transport chain for further ATP production. In the TCA cycle, three molecules of NADH are produced, making the correct answer 3.

Pyrimidines are one of the two types of nitrogenous bases found in DNA and RNA. They include cytosine (C), thymine (T), and uracil (U). Guanine (G) is not a pyrimidine; it is a purine. Purines, which also include adenine (A), have a double-ring structure, while pyrimidines have a single-ring structure. Therefore, G is not considered a pyrimidine.

GMP (guanosine monophosphate) is not an activated carrier. ATP (adenosine triphosphate) is a universal activated carrier molecule that provides energy for cellular processes. SAM (S-adenosylmethionine) is an activated carrier of methyl groups, which are important for various biological reactions. TPP (thiamine pyrophosphate) is an activated carrier of a two-carbon fragment in biochemical reactions. However, GMP is not involved in carrying energy or functional groups, making it the correct answer.

G1 phase is the division of cell growth that precedes Mitosis in the cell cycle. During this phase, the cell grows in size, synthesizes proteins and organelles, and carries out its normal functions. The G1 phase is followed by the S phase, where DNA replication occurs, and then by the G2 phase, where the cell prepares for Mitosis. Therefore, G1 is the correct answer.