I) Locus- the chromosomal site where a specific gene is located. A locus is a fixed position on a chromosome, like the position of a gene or a marker. Each chromosome carries ,many genes; human's estimated haploid (n) protein coding genes are about 20,000, on the 23 different chromosomes.
ii) Interference; the observed double crossover frequency differs from the expected double crossover frequency. Cross over interference is used to refer to the non-random placement of crossovers with respect to each other during meiosis. It results in widely spaced crossovers along chromosomes. Interference may exert its effect across whole chromosomes. As chromosomes in many eukaryotes are large, interference must be able to act over megabase lengths of DNA.
iii) Linkage- the tendency for genes located in close proximity on the same chromosome to be inherited together. Normally when two genes are close together on the same chromosome, they do not assort independently and are said to be linked. Whereas genes located on different chromosomes assort independently and have a recombination frequency of 50%, linked genes have a recombination frequency that is less than 50%.
iv) Recombination- the process by which a new pattern of alleles on a chromosome is generated. Genetic recombination is the production of offspring with combinations f traits that differ from those found in either parent. During meiosis in eukaryotes, genetic recombination involves the pairing of homologous chromosomes. This may be followed by information transfer between the chromosomes.
T- tall allele
t- dwarf allele
This cross needs to be between 2 plants with the same genotype, like Tt xTt
In this cross it would result in:
1/4 of the plants being tall homozygote- TT
2/4 of the plants being tall heterozygote- Tt
1/4 of the plants being dwarfs homozygote- tt
Answer:
By stopping the translation process, leading to a non-functional protein.
Explanation:
The genes of organisms are the protein-coding regions of the genetic material (DNA). They are expressed in a two step process to produce functional products e.g proteins that bring about certain phenotypes in the organisms. The two stages involved in gene expression are viz: transcription and translation.
During transcription, the gene (DNA) is transcribed into RNA molecule which is read in a group of three nucleotides called CODON during translation. Translation synthesizes an amino acid from each codon. A STOP CODON i.e. UUC, UUG and UUA signals the end of the translation process and brings it to an halt.
Hence, if a mutation i.e. a change in the nucleotide sequence, causes a stop codon to be produced during the expression of Lucy's ADA gene, the stop codon will signal the end of the translation process. Because the ADA protein was truncated, it will be non-functional i.e. not work in Lucy's body.
Answer:
CGTATC - DNA complementary strand- GCATG
CTTTCAAG- DNA complementary strand-GAAAGTTG
GAGACTTAC-DNA complementary strand-CTCTGAATG
Explanation:
Remember that the complementary sequence will be based on base pairing for DNA, so the A will pair with T, C with G
