Một gen (1 đoạn của phân tử ADN) có số Nu loại A bằng 1000 nu và bằng 2/3 số Nu loại X. a. Tính số Nu loại T, G,X của gen
b. Tính tổng số Nu của gen
c. Tính chiều dài của gen
d. Tính khối lượng phân tử của gen ( biết mỗi Nu có khối lượng phân tử là 300 đvC.
e. Khi gen này nhân đôi một lần cần bao nhiêu Nu tự do?
Giải:

relative dating involves things like higher layers are most recent than rocks lower in the sequence. this can be extended to the known sequence of fossils. rocks containing rabbit fossils are later than those containing dinosaur fossils.  

absolute dating methods mainly use radioactive elements that have known rates of decay and produce recognizable products. for example potassium 40 decays to produce argon. once a rock has solidified the argon is trapped. by measuring the argon and potassium0 you can get an accurate number for the age.  

some other methods are good for archaeological ages. dendrochronology involves recognizing the sequence of tree rings. the orientation of magnetized particles in baked clay can be used to date a fire.

hope this .. .

mass and weight are closely related because mass affects the weight of an object experiencing the effects of gravity. weight is the measure of the force of gravity on an objects's mass, while mass is the measure of how much matter there is in an object.

answer;

medical directors

explanation;

medical directors grants and supervises the privilege or permission to use an aed on an ambulance.

other roles of a medical director includes;

-provide medical leadership, including coordination with local ems and 911 centers.

-provide guidance in equipment selection and deployment

-develop guidelines for responder actions

-oversee medical care that is rendered through the program, including review of all responses to medical emergencies

-ensure appropriate initial training and skill maintenance

-assume overall responsibility for the conduct and operation of all patient care related activities