The immune system is a system of many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue.he ability of the immune system to respond to pathogens is diminished in both the young and the elderly, with immune responses beginning to decline at around 50 years of age due to immunosenescence. In developed countries, obesity, alcoholism, and drug use are common causes of poor immune function.
Yes, a 32-bit architecture is limited to addressing a maximum of 4 gigabytes of memory. Depending on the operating system, this number can be cut down even further due to reserved address space. This limitation can be removed on certain 32-bit architectures via the use of PAE (Physical Address Extension), but it must be supported by the processor.
Here is my understanding: A 32 bit machine is called 32 bit because its access granularity is 32 bits, and not because it can address 2^32 individual bytes. For example, the Pentium Pro is a 32 bit machine, but can address 2^36 bytes (in the physical memory, and not the virtual memory). This limits the amount of physical RAM to 64gigs. As far as 64 bit machines go, their word size is 8 bytes. Typically, they use 48 line address bus, thus can access 2^48 bytes in physical memory. (This will be the total amount of RAM it can support). But they can address 2^64 bytes in virtual memory.