The wall of the heart<span> consists of three </span>layers<span>: the epicardium (external </span>layer<span>), the myocardium (middle </span>layer<span>) and the endocardium (inner </span>layer<span>). The epicardium is the thin, transparent </span>outer layer<span> of the wall and is composed of delicate connective tissue.
</span>
Answer:
Regulatory sites e.g enhancers and silencers
Explanation:
Gene expression involves the synthesis of gene products usually proteins and RNA. However, a certain product might not be needed at all or in small quantity. Gene regulation mechanism is the process that makes this happen. Gene regulation is the mechanism that acts to induce or repress the expression of a gene.
Gene regulation involves controlling the rate and manner of gene expression which is achieved through a set of regulatory proteins called transcription factors. Transcription factors bind to specific regulatory nucleotide sequences and help to turn "on or off" specific genes in the DNA.
Transcription factors can either be ACTIVATORS or REPRESSORS depending on whether they boost or inhibit gene expression. The binding sites for these regulatory proteins called TRANSCRIPTION factors are the regulatory nucleotide sequences on the DNA called enhancers and silencers.
Answer:
The meaning of force? or gravity pulling the object towards the Earth.
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.
This sums up most of them
