What Are Shells Made of? Shells are primarily made of calcium carbonate. Cells in the mantle secrete proteins and minerals that form the shell. The proteins act as scaffolding for the calcium carbonate to bind. Calcium carbonate can form two types of crystals-calcite and aragonite. Calcite is ...
Via antigenic driftAntigenic drift is due to spontaneous mutations (e.g. point mutation) of the viralgene encoding haemagglutinin glycoprotein (antigen)Such mutations result in the production of new hemagglutinin proteins that areof a different conformation.Antibodies made against the original influenza ...
Enzymes are made fromamino acids, and they are proteins. When an enzyme is formed, it is made by stringing together between 100 and 1,000 amino acids in a very specific and unique order. The chain of amino acids then folds into a unique shape. That shape allows the enzyme to carry out...
The functional units of muscle fibers are calledsarcomeres. When viewed under the microscope skeletal muscle has a striped pattern. This is because of the molecular structure of the sarcomere. Muscles are made of thousands of sarcomeres stacked on top of each other. ...
Proteins are polymers of amino acids. Draw a general diagram of an amino acid. Describe three types of biological functions of proteins. Proteins are cleaved (cut) by proteases. How do these enzymes work? (a) Proteases cleave any carbon...
These are the FliFC–FliGD1 rotation, the change in domain swapping of FliGD2 and the ~25° rotation of FliMmid (Fig. 3g,h,k). Biologically, bound signalling proteins influence both the direction and rate of rotation. One of our CW data sets showed density within an ~40 Å cleft...
Enzymes are proteins made from amino acids. HowStuffWorks.com Earlier, we talked about the enzyme PDE. To better understand its function, consider that anenzymeis a specially folded protein that can speed up a chemical reaction. (For example, the articleHow Cells Workdescribes the maltase enzyme...
During the stationary phase, cells switch to a survival mode of metabolism. As growth slows, so too does the synthesis of peptidoglycans, proteins, and nucleic-acids; thus, stationary cultures are less susceptible to antibiotics that disrupt these processes. In bacteria capable of producing endospor...
It releases a mix of enzymes into the small intestine to break down carbohydrates, proteins, and fats. It's like having various kitchen gadgets for different cooking tasks, ensuring your food is properly prepared for absorption. Large intestine The large intestine is like the last stop on the ...
The nucleus and the other organelles are surrounded by the nuclear envelope; it is similar to the cell membrane. The nucleus contains something called chromatin which is made of RNA, DNA and nuclear proteins. DNA contains genetic material and also instructions to how to make our body work ...