Answer:
4. a
5. a
6. a
7. a
8. a
9. a
10. True
Explanation:
4. Units of inheritance in living organisms are known as genes. These genes exist in pairs in all organisms and a copy of each gene is passed down to the offspring during reproduction.
Correct option: a
5. Assuming the dominance of allele A over allele a:
AA x aa
Aa Aa Aa Aa
All the offspring will appear tall since the effects of allele a is masked by allele A.
Correct option: a
6. From the cross in (5) above, the genotypic ratio of the offspring is 100% Aa.
Correct option: a
7. Alternate forms of genes in living organisms are known as alleles. A copy of the alleles is usually passed down to the offspring during the process of reproduction.
Correct option: a
8. Phenotypes are the physical appearance of organisms. They are physical interpretation of genes.
Correct option: a
9. The law of segregation was postulated by Gregor Mendel. It states that gene pairs segregate during the process of meiosis and then randomly unite during the process of fertilization.
Correct option: a
10 Heterozygous organisms have two different alleles for the same genes. For genes that obey Mendelian laws, heterozygous condition is characterized by one dominant and one recessive alleles.
Electron sharing occurs so that atoms attain the configurations of noble gases
Answer:
Three examples of fossil fuels are:
1). Petroleum
2). Coal
3). Natural gas
Answer:
A transcription factor that binds to a gene first and facilitates binding of other transcription factors is called an activator transcription factor.
Explanation:
Transcription factors are proteins that regulate the transcription of genes.Transcription is the process where a gene's DNA sequence is transcribed into an RNA molecule. Transcription is a key step in using information from a gene to make a protein.
The enzyme RNA polymerase, which makes a new RNA molecule from a DNA template, must attach to the DNA of the gene. It attaches at a spot called the promoter.In eukaryotes, RNA polymerase can attach to the promoter only with the help of basal (general) transcription factors. They are part of the cell's core transcription toolkit, needed for the transcription of any gene.
A typical transcription factor binds to DNA at a certain target sequence. Once it's bound, the transcription factor makes it either harder or easier for RNA polymerase to bind to the promoter of the gene.
Some transcription factors activate transcription, other transcription factors repress transcription.