Red-green color blindness is inherited as an x-linked recessive (xc). if a color-blind man marries a woman who is heterozygous for normal vision, what would be the expected phenotypes of their children with reference to this character? in your answer, specify in your phenotype descriptions the gender of the children. (for example, don’t just say 75% of the children would be colorblind – you would instead say 100 % of the daughters would be colorblind and 50% of the sons would be colorblind. note that this is not a correct answer; it is just to give you an idea of how to explain the correct phenotypes of the cross.)

25% colorblind daughter: 25% colorblind son: 25% carrier daughters with normal vision: 25% normal son.

Explanation:

The genotype of a color-blind man is X^cY and the genotype of the heterozygous carrier female is X^cX. A cross between X^cY and X^cX would produce a progeny in following ratio=  

25% colorblind daughter: 25% colorblind son: 25% carrier daughters with normal vision: 25% normal son.

Therefore, the couple is likely to have 50% normal son and 50% affected son. Likewise, the couple is likely to have 50% normal daughters and 50% colorblind daughters.  

question#1

ans:

cell is the basic unit of organization of all living things. cells are often called the building block of life and it is the smallest unit of life. the study of cell is called cell biology. cell consists of cytoplasm enclosed within membrane, which contain bio-molecules such as proteins and nucleic acid.

two third of cell is water, which means that two-third of your whole body is water. the rest is the mixture of molecules, mainly proteins, lipids and carbohydrates.

question#2

ans:

organ:

an organ is a group of tissues specialized to form a functional unit. an example is the heart in animals.

organ system:

an organ system is a group of several organs whose functions are synchronized to release an effective action in a living organism. an example is digestive system.

question#3

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#4

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system—working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#5

our body works because of the interactions that happen between organs and organ systems.  

for example:  

the heart to regulate blood flow throughout the body. the blood carries oxygen and nutrients to the cells and carries carbon dioxide and waste away from the cells. body systems work together in maintaining a constant internal environment. when this balance is disrupted, the body systems may not function properly, and human health can suffer.   you start to feel bad.