I believe it's called the urethra
<span>The hydrogen-oxygen ratio is different.
Carbohydrates and lipids are macromolecules. These macromolecules or biomolecules help organisms to conduct and execute certain cellular activites making them alive and thrive in their certain environment. It is only that carbohydrates are more efficient at producing energy than lipids.</span>
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.
Active transport is the moving of molecules across the membrane of the cell against the concentration gradient with the use of ATP.
Low to high concentration. Concentration gradient is the diffusion (movement of molecules from regions of low concentration) from high to low with the gradient. Active transport is from low to high, against the gradient.
Initiator proteins break hydrogen bonds separating short length of DNA, AT base pairs are held together by fewer hydrogen bonds than GC pair. Thus AT pairs are easier to pull apart, At rich regions are typically found in the replication origins. Replication origins are site at which DNA is first opened.
