Sttrcuture And Function Id Dna Flashcards

Question

Mitopchondriome

Answer 1

Genome of mitochondria

Answer 2

Description of all chemical modifications of dna ans histone proteins that regulate gene expression within the genome

Answer 3

Combination of alleles for a particular gene or locus

Answer 4

-small changes in dna sequence -rearrangemnts of genes and chromosomes -deletions and insertions of dna sequences -increasing or decreasing Chromosomal sets

Answer 5

Neutral Beneficial Harmful

Answer 6

are random, inheritable (usually small) alterations in the sequences of a genome. Mutations can change the phenotype. Some of them (which are neutral) do not change the phenotype

Answer 7

are physical or chemical factors that increase the rate of mutations (in this case they are called induced mutations). Mutagens can modify DNA in different ways, but those changes are considered as mutations when they are inherited.

Answer 8

Point mutations could be of two general categories: - base–pair substitutions (one nucleotide is substituted with another); - base–pair insertions or deletions (the nucleotides are inserted [added] or deleted Effect : Base–pair substitutions may lead to silent, missense, or nonsense mutations. Insertions and deletions are mutations that have much more dramatic, disastrous effects on resulted proteins than substitutions do. This is because mRNA is read as triplets of nucleotides (one triplet for one amino acid) during translation (protein synthesis); and the insertion or deletion of nucleotides alter the reading frame of grouped triplets, leading to a shift in genetic message (a frameshift mutation).

Answer 9

ubstitution is called a silent mutation if it has no effect on the encoded protein (because of the redundancy of the genetic code: a few different triplets could encode the same amino acid). A substitution is a missense mutation if the altered codon causes encoding for a different amino acid (makes not right sense). A substitution is a nonsense mutation if a codon for an amino acid is converted into a stop codon (it terminates translation, and a protein could be truncated

Answer 10

a point missense mutation. The allele causing sickle–cell disease differs from the wild–type (normal) allele by a single DNA base pair (A instead T leads to the synthesis of the aminoacid valine instead glutamine in the molecule of haemoglobin)

Answer 11

Mutation which causes abnormality in cartilage formation that delays bone growth,active mutant receptor leads to shortened bones 50% chance of passing the gene to children

Answer 12

Hutchinson-Gilford progeria syndrome: autosomal dominant syndrome GGC mutates to GGT

Answer 13

CML patients possess an abnormally short chromosome 22 (called Philadelphia chromosome), and an abnormally long chromosome 9 that are resulted from the reciprocal translocation. They have leukaemia, due to unregulated growth of predominantly leukocytes in the bone marrow (disorder of stem cell differentiation).

Answer 14

most common type of viable human aneuploid Characteristic facial features for a child with Down syndrome. The other signs are short stature, heart defects, susceptibility to respiratory infection, and mental retardation. The patients are prone to leukemia and Alzheimer′s disease. . They have a shorter life span (some live to middle age). Most are sterile and sexually underdeveloped.

Answer 15

In general: Functions in heredity (based on exact copying of DNA during replication). Functions in variations (based on recombination of DNA and different types of genome alterations – mainly as errors in replication of DNA and segregation of chromosomes). DNA variations are implicated in evolution of species. In many cases, however, they lead to serious diseases Coding functions Non coding functions