Answer:
irregular ovulation ( D )
Explanation:
Irregular ovulation is not one of the common causes of infertility. , The quality of the eggs in women/ size of the eggs affect the fertility status in women and this quality is affected by declining hormone levels that occur with age. while in the case of irregular ovulation the woman will have to put in more effort to determine her most fertile time but it won't affect her ability to conceive in general.
Answer:
True
Explanation:
Pacemaker cells, unlike other neurons in the body, can depolarized themselves (and therefore can fire action potentials) without the need of an external innervation of the autonomic nervous system.
Each class of pacemaker cells has its own intrinsic rate.
For example, sinoatrial node rate is 60-100 bpm (the normal heart frequency).
The atrioventricular node is also part of the electrical conduction system of the heart. When the sinoatrial node fails, atrioventricular node takes the lead (40-60 bpm).
Answer:
Mainly people undergoing surgery.
Gradually, came sushi and karate from Japan, and delicatessens from Italy and Germany, and 18 speed bikes from several European countries. Chinese food cooked and served by Chinese Canadians, not all of it authentic Cantonese or Szechuan or whatever, got steadily more popular as I grew up. And pizza. And espresso coffee. And holopchi from Ukraine and pyrogies from Poland. French perfumes. Mexican leather goods. Smorgasbords. All of these were virtually unknown to me when I was in grade 1, but were common by the time I was in university. I could go on and on. Other countries are going through similar experiences, some more slowly that Canada has, some actually a bit faster.
Then there are the subtler things, the ways of thinking and living. Yoga, tai-chi, zen, existentialism, deconstructionism, post-modernism, Marxism, supply side economics and on and on.
This world is a globalized one now, and it has been getting gradually more and more so for a long time. There is no going back. We learn to live together on Starship Earth or we exterminate ourselves.
