E=hv is an equation important when dealing with light. E refers to the energy of a photon; h is Planck's constant and v is the wavelength. According to this equation, light particles called photons travels in packets of energy. This is important in pv cells because this is the technology used to harness solar energy which is converted to electricity. The amount of energy should be estimated to know the appropriate material of construction of the pv cell to achieve optimum conditions. In this way, the pv cell could maximize the sun's energy.
Answer:
Dogs are wonderful human companions. They are the first species that humans domesticated and they have a long history of close relationships with people.
If you spend any time with dogs (I have two wonderful adopted dogs who shower me with affection and fur), then you see first-hand the many ways that dogs can respond to their owners. A dog may treat a stranger with suspicion, but dances with joy when its owner returns. Indeed, when one of our grown children returns after a long absence, the dogs respond with excitement.
Answer: alternating dark and light bandsof protein filaments
Skeletal muscle fibers contain striations that can be described as alternating dark and light bands of protein filaments. Actin, tropomyosin, and troponin are among the protein filaments. The dark bands are the so-called A bands. Alternating light bands are referred to as I bands.
Given the answers;
a) Reptiles
b) Cactus plants
c) Small birds
d) Crabs and crayfish
The answer is C. Small birds.
On his visit to the Galapagos Islands, Charles Darwin discovered several species of finches that varied from island to Island, which helped him to develop his theory of natural selection.
The brain, heart and the skeleton are the integral parts of the nervous system, circulatory system and the skeletal system respectively. The nervous system is made of the brain and the spinal cord with neurons as the structural and functional units of it. The circulatory system is made up of the heart and its blood vessels. The skeletal system is made up of the bones and cartilages making the skeleton of the body.
The brain regulates the heart beat and the blood pressure. The heart nourishes the brain with oxygen and nutrients by pumping blood. The bone cells are nourished by the blood pumped by the heart. The bone marrow of the skeleton produces the new red blood cells which enter the blood circulatory system. Also the the ribs and the breast bone of the skeleton protects the heart, the cranium of the skeleton prtects the brain. The bones also provide calcium which is necessory for the functioning of the nervous system. The brain controls the skeletal movements of the body. The cerebellum of the brain controls the voluntary skeletal movements and the medulla controls the involuntary skeletal movements of the body. The blood brain barrier formed by the endothelial cells of the capillary walls located in the brain seperates the circulating blood from the brain and the extraclellular fluid in the central nervous system and acts as a selective semipermeable border.
