Main chemical Change explained by Lavoisier
Answer:
The mechanisms of transport across the cell membrane are as follow: 1- simple diffusion, 2- facilitated diffusion, 3- primary active transport and 4-secondary active transport
Explanation:
The cell membrane is a selectively permeable structure capable of transporting substances by different mechanisms. Simple diffusion is a type of passive transport (i.e. does not require energy) where non-polar molecules (e.g. O2, CO2) pass across the membrane by a process that does not require energy from the cell. Facilitated diffusion is another type of passive transport where larger polar molecules (e.g., glucose and amino acids) pass across the membrane by using specific transmembrane integral proteins. On the other hand, primary active transport is a type of active transport that uses chemical energy (e.g., ATP) to move substances such as metal ions (Na+, K+, Ca2+) across the cell membrane against their concentration gradient. Finally, secondary active transport is another type of active transport where transporter proteins are used to couple the movement of ions (e.g., H+ protons) down their electrochemical gradient to the transport of another ions/solutes against their concentration/ electrochemical gradient.
Answer:
D. We know more about the Cenozoic era because this the most recent time period in the history of the Earth, and we have more information available to study.
Explanation:
The Cenozoic era is the era that is by far the best studied and known by the scientists. The main reason for this is that this era is the most recent one, and it is actually the era we live in. Because it is the most recent era, the Cenozoic is abundant with lot of evidence of what has happened in it. The fossil records are very rich as the fossils didn't had that much time to totally decompose. The rock layers are much younger, so they contain much more detailed evidence of the plant life, climate, changes in the environment. The oceanic crust is also in abundance, which is not the case with the other eras as the oceanic crust is constantly suducted.
Overexploitation, Habitat loss, invasive species, climate change
Chromosomes are made of condensed coils of DNA. Genes are segments on a chromosome that carry the code for a specific trait. Alleles are contrasting forms of a gene. Dominant means that a particular trait will be visible. Recessive means that a trait will be hidden (unless it is paired with another recessive gene). A trait is how the gene is seen. For example, eye color is a trait.
