Answer:
Crossing two chickens heterozygous for the trait feather color, when brown feathers are dominant over red feathers, will produce offspring with brown and red feathers in a brown:red phenotypic ratio of 3:1.
Explanation:
Knowing that in chickens brown feathers are the expression of the dominant allele (B) and the recessive allele is red (b), crossing two heterozygous individuals (Bb) will result in offspring that are likely to have brown or red feathers.
The cross can be represented by a Punnett Square:
<u>Bb X Bb cross
</u>
alleles B b
B BB Bb
b Bb bb
Where the result is:
<u>Genotypes</u>:
<u>Phenotypes</u>:
- Brown feathers, 75%
- Red feathers, 25%.
In this case, the probability of having brown or red feathers is 3:1.
Transcription is a key regulatory<span> point for many</span>genes<span>. Sets of transcription factor proteins bind to specific DNA sequences in or near a </span>gene<span> and promote or repress its transcription into an RNA. RNA processing.</span>
The answer to your question is "maggots"
Answer:
The correct answer is c) are plant cells.
Explanation:
The cells cannot be animal cells, because they have not wall (this kind of cells has only plasma membrane). In addition, eukaryotic cells have membrane-bound organelles (which are surrounded by a phospholipids membrane, such as endoplasmatic reticulum, Golgi apparatus, lysosomes, etc.), whereas prokaryotic cells lack them. Since plant cells are eukaryotic and bacterial cells are prokaryotic, the cells you are looking are plant cells.
Oxygen entered the Earth's atmosphere after the appearance of the Great Oxidation Event (Great Oxygenation Event). The Great Oxidation is the first mass extinction on Earth.
The Great Oxidation lasted 2.4 to 2.0 billion years ago.
Oxygen appeared on Earth thanks to cyanobacteria using photosynthesis.