What phenotypic ratio would you expect as a result of a test cross between a dihybrid organism and one that is homozygous recessive for alleles at two independent loci?
a. 3:1
b. 9:3:3:1
c. 1:1:1:1
d. 1:2:1
e. 9:4:2:1
Answer:
c. 1:1:1:1
Explanation:
When a heterozygous individual for two genes is test crossed with a double homozygous recessive individual, the progeny is obtained in 1:1:1:1 phenotypic ratio. This occurs as the heterozygous dominant individual forms four types of gametes in 1:1:1:1 ratio while the homozygous recessive individual would form only one type of gamete having one recessive allele for each gene.
For example, a test cross between TtRr (tall and red) and ttrr (short and white) would produce a progeny in following ratio=
1 tall, red: 1 tall, white: 1 short, red: 1 short, white
Here, T= tall, t= short, R= red, r= white
Answer:
Stem cell is the special type of cell that can differentiate to give any cells in the body. Cell therapy nowadays are using stem cell in order to replace damaged tissue.
Researchers are finding out ways to treat diseases like diabetes, Parkinson's, spinal cord injury and heart injury etc. These cells have the ability to repair damaged heart cells after a heart attack. They can also treat neurological problems.
Answer:
I believe the correct answer would be spem cells. Please mark brainliest.
Explanation:
The answer that fits the blank provided above is STEROIDS. Steroids are fat-soluble signal molecules. This is one of the derivative compounds of cholesterol along with Vitamin D and bile salts. All steroid hormones are considered as a derivative of cholesterol. The answer for this would be option D.
Answer:
Please find the explanation below
Explanation:
Deoxyribosenucleic acid, commonly called DNA is the stored form of genetic material in living cells. It contains the information needed by an organism to survive. A segment of the DNA that encodes the necessary information needed to produce a particular protein that determines a trait is called GENE.
The DNA consists of long polynucleotide chains, hence, due to Its length, it cannot git into the cell. The cell then devises a means by wrapping the long strands of DNA around certain proteins called HISTONES. This initially forms a NUCLEOSOME structure, then continuous wrapping around histones and condensation forms the visible CHROMOSOME structure.
Now, the CHROMOSOME contains the DNA molecule, which contains protein-coding segments called GENES. The information contained on the gene is used to produce a protein that is responsible for a particular TRAIT in the organism.
