What is global warming?

What is global warming?

Extra carbon dioxide in the atmosphere enhances a natural process known as the greenhouse effect. Greenhouse gases, such as carbon dioxide, absorb heat and release it slowly. Without this process, Earth would be too cold for life to survive. Over the past 200 years mankind has increased the proportion of sphere, primarily by burning fossil fuels. The higher levels of greenhouse gases causing our planet to warm-global warming. Also gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, chlorofluorocarbons, and other pollutants.

The heart circulatory system

Heart circulatory system

We are going to speak about the heart how it work in our body but before we  start we have single circulation system and double circulation system. The deferens between single circulation and double circulation .Single circulation system : the blood is pumped from the heart to the gas exchange and directly to the rest of the body .But the double circulation system: the blood is pumped from the heart to the  gas exchange organ back to the heart and then to the rest of the body. Know we are going to speak about double circulation system how it works in human body.

The heart consists of four parts Right, left atrium it is in the top of the heart and right, left ventricle this is down of the heart as we can see from the photo. Also we have two circulations pulmonary and systemic. There are also two valves that allow the blood to move in the heart. The pulmonary is the small circulation it works like this: it take the blood from the right ventricle with carbon dioxide and filtrate it in the lungs to oxygen after this it goes to the left atrium. The systemic is the biggest circulation it work like this: it take the filtrate blood from left ventricle  with oxygen and pass it to the all of the body, in the capillaries oxygen change to carbon dioxide after this go to right atrium with carbon dioxide and start to repeat the circulation again and again. This the first way that the heart can work. Secondly is medulla it is in the brain that can make the heat work if there is a problem in the heart.

Is global warming really caused by humans?

Global warming caused by humans?

Since 1958 scientists observing in Hawaii have taken continuous measurements of atmospheric carbon dioxide. The levels go up and down  by changing the seasons, but overall they show a relentless rise. Bubbles of gas from ice cores and the chemical composition of fossil shells provide us with a record of atmospheric carbon dioxide going back millions of years. There have been warm periods in the past where carbon dioxide was at levels similar to those seen today. However, the rate of change that we see today is exceptional: carbon dioxide levels have never risen so fast. By 2000 they were 17% higher than in 1959. Accompanying this rapid increase in carbon dioxide we see a rise in average global temperatures. Warming in the past 100 years has caused about a 0.8 C increase in global average temperature. Eleven of the 12 years in the period 1995 - 2006 rank among the top 12 warmest years since 1850. There is little doubt that humanity is responsible for the rapid rise in carbon dioxide levels. The rise in temperature that has accompanied our fossil fuel addiction seems too much of a coincidence to just chance. Most people now agree that our actions are having an effect on Earth's climate.