Fossils are found of giraffes with short necks.
Lamarck believed the giraffes stretched their necks and passed it to their offspring
necks grew longer due to stretching.
giraffes need long necks for food and evolution provided it to them
Answer:
Is it true that all cells have the same genes, but different genes are active in different cells.
No, all cells are made up of a gene which is inherited from the parents cell. The gene is located in the DNA which is found in the nucleus of every living cell
Explanation:
Answer:
False
Explanation:
The papillary muscles of both right and left ventricles began to contract shortly before the other ventricular muscles (systole) so that they can take up the slack on the chordae tendineae as the full force of ventricular contractions sends blood against the atrioventricular (AV) valve flaps.
They prevent the backward flow of blood to atria from ventricles. So if they contract after the ventricle systole they would not be able to perform their job.
The pedigree above shows the family history of the recessive blood disorder sickle-cell anemia. What are the chances of the child having the desise or carrying the gene for the disease?
A. Child I has no change of having the disease and no change of caring it
B. Child i has a 50 present chance of having the disease and a 50 precent chance of carrying the disease
C. Child I has no chance of having the disease and a 50 present chance of carrying the disease
D. Child I has a 100 present chance of having the disease and a 100 present chance of carrying the disease.
Answer:
C. Child I has no chance of having the disease and a 50 present chance of carrying the disease
Hope that helps and good luck
~May
Answer:
Carbon is the chemical backbone of life on Earth. Carbon compounds regulate the Earth’s temperature, make up the food that sustains us, and provide energy that fuels our global economy. Carbon moves from one storage reservoir to another through a variety of mechanisms. For example, in the food chain, plants move carbon from the atmosphere into the biosphere through photosynthesis. They use energy from the sun to chemically combine carbon dioxide with hydrogen and oxygen from water to create sugar molecules. Animals that eat plants digest the sugar molecules to get energy for their bodies. Respiration, excretion, and decomposition release the carbon back into the atmosphere or soil, continuing the cycle. The ocean plays a critical role in carbon storage, as it holds about 50 times more carbon than the atmosphere. Two-way carbon exchange can occur quickly between the ocean’s surface waters and the atmosphere, but carbon may be stored for centuries at the deepest ocean depths. Rocks like limestone and fossil fuels like coal and oil are storage reservoirs that contain carbon from plants and animals that lived millions of years ago. When these organisms died, slow geologic processes trapped their carbon and transformed it into these natural resources. Processes such as erosion release this carbon back into the atmosphere very slowly, while volcanic activity can release it very quickly. Burning fossil fuels in cars or power plants is another way this carbon can be released into the atmospheric reservoir quickly.Human activities have a tremendous impact on the carbon cycle. Burning fossil fuels, changing land use, and using limestone to make concrete all transfer significant quantities of carbon into the atmosphere. As a result, the amount of carbon dioxide in the atmosphere is rapidly rising; it is already considerably greater than at any time in the last 800,000 years. The ocean absorbs much of the carbon dioxide that is released from burning fossil fuels. This extra carbon dioxide is lowering the ocean’s pH, through a process called ocean acidification. Ocean acidification interferes with the ability of marine organisms (including corals, Dungeness crabs, and snails) to build their shells and skeletons.