Answer:
Explanation:
We are asked to find how much of a 40 gram sample remains after 12 years.
Iron-55 has a half-life of 3 years. Therefore, after 12 years, 4 half-lives have been completed.
- 12 years/3 years = 4 half-lives
Every time a half-life is completed, half of the sample's mass decays. Remember we start with a 40 gram sample.
- 1 half- life: 40 g / 2 = 20 g
- 2 half-lives: 20 g / 2= 10 g
- 3 half-lives: 10 g / 2 = 5 g
- 4 half-lives: 5 g / 2 = 2.5 g
There is also a formula that can be used to solve this problem.
Where A₀ is the initial amount, t is the time, and hl is the half-life.
We know 40 grams is the inital amount, 12 years is the time, and 3 years is the halflife.
After 12 years, <u>2.5 grams </u> of Iron-55 will remain.
Nucleus. it’s the main part that sorts and tells cells what to do and where to go.
Answer:
a paper plane also known as and paper aeroplane in American English or paper aeroplane in British English is it toy aircraft usually a glider made out the single folded sheet of paper or paper boat a simple noise heavy paper plane truth like a dot is also known as paper
1. Regulation of glucose blood levels is an example of negative feedback mechanism.
Negative feedback mechanism is a control mechanism involved in homeostasis maintain, in this case maintenance of glucose blood levels in normal range.
Negative feedback mechanism contains sensory system that detects the changes, control system that responds to change and activates mechanisms of effector system that reverse the changes in order to restore conditions to their normal levels.
• Pancreatic cells-sensors
• Insulin-control system
• Body cells- effector cells
2. Blood glucose levels change throughout the day because of the food consumption, but in healthy individuals levels of glucose are successfully regulated via the mechanism of hormones such as insulin and glucagon in a process called glucose blood regulation.
This tight regulation of pancreatic hormones is referred to as glucose homeostasis. Insulin lowers blood sugar and glucagon raises it.
3. If the beta cells are destroyed by an autoimmune disease (immune system attacks its own cells), there would be no insulin release, and consequently, the glucose blood levels would be increased.
Diabetes type I is a metabolic disorder caused by the destruction of insulin-producing pancreatic beta cells.
The answer would be that the e<span>xcretion and the </span>liver<span>. Excretion in mammals. Excretion is the removal of potentially harmful or toxic substances from the </span>body<span>. These substances are usually waste materials </span>produced by<span> complex chemical reactions taking place in living </span>cells<span>. Enzymes catalyse the reactions.</span>
