Bishop Year 13 Biology

- Recap of types of genetic mutation - Definition of "operon" as "a cluster of genes under the control of a single promoter" - Definition of promoter as "a region of DNA near the start of a coding sequence where RNA polymerase can bind to begin transcription" - Introduction of the need for the lac operon in E.coli (usually respires using glucose so it would be wasteful to express necessary genes all the time, genetic switch required to facilitate detection of lactose followed by expression of necessary genes - Discussion of the role of lactose permease (transport protein) and beta-galactosidase (hydrolyses the disaccharide) HOMEWORK - get completed PLCs emailed in AND revise this topic for mini test Thursday

- Discussion of the broad categories of mutations (chromosome and gene) - Division of gene mutations into point and indel mutations - Division of point mutations into silent, missense and nonsense mutations (with examples) - Comparisons of the varying effects of the different types of mutations, with indel and nonsense often being the most detrimental - indel mutations cause a FRAME SHIFT in most circumstances meaning that every subsequent triplet is affected by the mutation - Discussion of the need for differential gene expression - this allows cells to become SPECIALISED - they need to express different genes at different times - Discussion of the different types of gene expression control/regulation: 1. Transcriptional 2. Post-transcriptional 3. Post-translational HOMEWORK - revise for mutations quiz, complete the mutations questions sheet and complete the year 12 PLC and bring on a USB

- The Biology mock exam is on Monday 12th - The duration of this paper is 1 hour 35 minutes - It will contain a combination of multiple choice, short answer, calculation, extended answer and practical based questions - The main topic content with be year 1, photosynthesis, respiration and PAGS

- Recap of the structure and function of adrenal glands including location (above the kidneys), different regions and the functions of different regions - LEARN! - Recap of the role of hormones in negative feedback - every hormone is released from a specific gland and travels in the blood around the entire body. The hormone is detected by certain TARGET CELLS and an EFFECT is produced - Control of blood glucose is regulated by the hormones GLUCAGON and INSULIN - They are released from the ISLETS OF LANGERHANS in the pancreas - Glucagon is released when blood glucose levels fall. It effects the liver and results in an INCREASE in the concentration of blood glucose - Insulin is released when blood glucose levels rise. It effects the liver and results in a DECREASE in the concentration of blood glucose New associated key words:  GLUCONEOGENESIS: Production of new glucose in the liver and muscle cells from lipid molecules. Stimulated by GLUCAGON GLYCOGEN...

- Summary of ecothermy and endothermy including adaptations to these lifestyles FOR EXAMPLE: Many reptiles with bask in the sun to increase their body temperature in the morning which enables them to become more active - Introduction of key words relating to the topic including: endocrine gland, exocrine gland, target organ, hormone, protein hormone, lipid hormone - Explanation of the different modes of action of protein hormones vs. lipid hormones - PROTEIN HORMONES - protein hormones bind to cell surface receptors and initiate G proteins which activates adenyl cyclase producing the second messenger cAMP - STEROID HORMONES - diffuse directly across the membrane and bind with receptor molecules in the cytoplasm forming hormone-receptor complexes. These then cross into the nucleus and act as transcription factors HOMEWORK - 1. revise for the mock exam! 2. Write an essay explaining how the release of insulin is controlled and how this helps to regulat...