Search over 10,000 free study notes

DNA replication is a multi stage process which is carried out in the nucleus of the cell. We know that DNA is in a double helix structure and for replication to occur it must be unwound into two single st...

Biology A-level is examined by year. Year 1 is examined in paper 1 and year 2 is examined in paper 2. Paper 3 consists of content from both years 1 and 2. When revising content for the papers it is impera...

Atherosclerosis occurs when the endothelium of a blood vessel becomes damaged. This may due to various reasons such as high blood pressure or toxins from cigarette smoke. This causes an inflammatory respo...

Vaccines provide a dead/inactive form of bacterial meningitis. Phagocytes such as macrophages recognise the antigens of bacterial meningitis as foreign so engulf the pathogen forming a phagosome. The lyso...

In skeletal muscle there exists a thick filament, myosin, and a thin filament, actin. For contraction both of these filaments need to interact causing a power stroke and muscle contraction. At rest, the m...