Cells of Escherichia coli transport lactose via lac permease,glucose via the phosphotransferase system, and maltose viaan ABC-type transporter. For each of these sugars describe:(1) the components of the transport system and (2) the sourceof energy that drives the transport event.

Is the H+/sucrose cotransport system involved in passive or active transport? How do you know?

Which of the following is CORRECT concerning the ABC transporter proteins? O They do not undergo conformational changes. They are passive transporters. They hydrolyze ATP to produce AMP and diphosphate. They transfer a phosphate to a conserved Asn residue. None of these are correct.

Is the movement of sodium through SGlut-1 during co-transport simple diffusion, facilitated diffusion, active transport, or secondary active transport? And is the movement of glucose through SGlut-1 during co-transport simple diffusion, facilitated diffusion, primary active transport, or secondary active transport?

While endocytosis and exocytosis refer to the direction in which a vesicle moves into and out of a cell respectively, it is important to think about what is being moved with and within the vesicles. To demonstrate how this process is utilized in human cells we will focus on the human body's insulin response. The purpose of the insulin response is to create a pathway for glucose entry into cells by releasing glucose transporters into the membrane. Cell Type #1- insulin producers: In humans, pancreatic B-cells create steroid insulin that can be packaged into vesicles starting at the ER. These vesicles are prepared for exocytosis so that the insulin can be released from the pancreatic B - cells and get into the bloodstream when signaled to do so. When glucose is present in the blood stream these cells will release the pre-packed insulin into the blood stream. Cell Type #2- insulin responders: Other cells do not produce insulin but instead respond when they have received the insulin signal…

The uptake of l-ascorbate (vitamin C) and its oxidized form, dehydro-l-ascorbic acid (DHAA), was evaluated in brush border membrane vesicles isolated from adult human small intestine. Ascorbate uptake was Na+-dependent and potential-sensitive (Km, 200 umol/L), whereas DHAA transport occurred through Na+-independent facilitated diffusion (Km, 800 µmol/L). If the Vmax of vitamin C import through channels is 401µmol/min/cm2, what import rate would you expect if the lumen contained 133 µmol/L of the version of vitamin C that moves through them?

Is endocytosis a type of active transport or passive transport, or neither type of transport? Explain.

In eukaryotic cells, metabolic pathways occur in specific locations, such as the mitochondrion or the cytosol.What sort of transport processes are required as a result?

Cargo proteins are transported through the Golgi apparatus to the trans-Golgi network, where they are sorted into various vesicles that are targeted to different destinations. What is the role of vesicles in -cargo protein transport through the Golgi apparatus?

Facilitated diffusion and active transport are two different mechanisms that the cells use to transport molecules into and out of the cell. Compare and contrast these two types of cellular transport.