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Ecosystems, Energy, DNA, And The Human Body

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In science class, we learned about the following units: evolution, ecosystems, climate change, cells, energy, DNA, and the human body. Many of these subjects influence each other or are related. Examples are ecosystems being impacted by climate change, information of the cell being coded in the DNA, and energy powering the human body. All of the covered subjects relate to evolution in some way. Evolution is the process of things changing and adapting over long periods of time and is based on survival of the fittest, which is also called natural selection. A variation in traits gives advantages in competition with other animals or within the species, which is influenced by selective pressure, for example food sources, habitat/shelter, weather/temperature. …show more content…

There are six different types of energy: Kinetic, thermal, electromagnetic, chemical potential, spring potential and gravitational potential. Kinetic energy is the energy of movement. Thermal energy is kinetic, only on a molecular level. As molecules speed up, they become warmer. Electromagnetic energy is energy in waves, for example light or microwaves. Chemical potential energy is energy stored in chemical bonds, which break when it is released. Spring potential energy is energy stored in any type of spring. Lastly, gravitational potential energy is energy gathered in an object as it moves further away from the force of gravity. None of these forms of energy are ever created or destroyed, they only change forms. One example of gathering this energy is photosynthesis. Plants gather energy from the sun using photosynthesis. During cellular respiration energy is released in a form usable for actions the cell requires. Energy relates to evolution because the ways of transformation of energy have changed. For example the chloroplasts are specialized cells to collect energy from the sun, they evolved from the simple prokaryotic …show more content…

Many of these have elements that maximise or increase the surface area. The human body is a specialized organism that has many body systems working together to provide the necessities to survive. The five main systems are circulatory, respiratory, digestive, excretory, nervous and hormonal. The circulatory system is responsible for transporting blood through the body. It is pumped by the heart through the arteries and capillaries to the individual cells, where O2 and nutrients are exchanged for CO2 and other waste products. In the veins, transported back to the heart, CO2 gets eliminated after reaching the lungs/respiratory system. The respiratory system provides the body with oxygen, and eliminates CO2, its main organ is the lungs. The digestive system takes in food and fluids to supply the body with nutrients, which are made usable and then absorbed. The non absorbable leftovers and the waste get eliminated from the body. Important organs of the digestive system are the stomach, intestines, pancreas, and liver with the gallbladder. The excretory system eliminates ammonia/nitrogen waste. Main organs are the kidneys, ureter, bladder, and urethra, which concentrate, channel and store the urine. The nervous system controls the body, as well as the senses. The main organ is the brain and spinal cord, the essential nerve cell is called a neuron. The human body connects to evolution

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