Summary The sequence of one heart beat ending to the beginning of another is known as the cardiac cycle The heart consists of two pumps that work together where both sides of the heart relax and contract with one another Systole is the repetition in contractions of the heart chambers Diastole is the relaxation of …
Summary Atherosclerosis is a progressive disorder and primarily an inflammatory disease It is caused by atheroma’s and marked by the narrowing of arteries by the hardening done by plaques Atheroma is the flaky material made up of lipids (cholesterol and lipid), macrophages, calcified lesions and fibrous tissue that are present nearest the lumen of an …
Summary of Light Reactions of Photosynthesis Light energy behaves both as electromagnetic waves and discrete particles, measured in photons. Pigments absorb visible light – important pigments in photosynthesis ar chlorophyll a, chlorophyll b and carotenoid The light-dependent reactions of photosynthesis make ATP and NADPH Photosystems I and II are complexes that work together to absorb …
Overview of Photosynthesis Summary Green plants and other organisms convert light energy into chemical energy through photosynthesis Photosynthesis is essential for almost all light on earth – either directly or indirectly Chloroplasts in the leaves of plant cells are the organelles in which photosynthesis takes place Chloroplasts contain chlorophyll which absorbs the light energy Thylakoids …
Summary box The Calvin cycle uses carbon dioxide to synthesise sugar Carbon dioxide enters the plants through the stomata of the leaves Carbon dioxide is incorporated into a 5 carbon sugar, RuBP, which immediately forms two molecules of 3-PGA. This is catalysed by rubisco. 3-PGA is converted to G3P, with 1,3-biphosphoglycerate as an intermediate, requiring …
Summary box for Types of Mutations Mutations occur through various mechanisms that can impact genes, chromosomes, and outcomes differently. Mutations can occur on a single nucleotide scale (at the level of point mutations), or on a much larger scale (where segments of whole chromosomes are affected. Substitution of nucleotides can be synonymous (silent) or non-synonymous …
Summary box Mutations describe changes to a DNA sequence and are associated with both disease and evolution Mutations can occur spontaneously in all cell types, but will only become part of the future generation’s genome sequence when they occur in the parental germ line Mutations can occur due to exposure to chemicals, environmental factors, or …
Definitions: Immunity – can be defined as the capacity to recognise the intrusion of material foreign to the body and to mobilise cells and cell products to remove that sort of foreign material with great speed and effectiveness. Pathogen – a disease-causing micro-organism. Reservoir – The place where the pathogen is usually found. Endemic – …
Genetics is the study of DNA and hereditary changes in living organisms. The idea that species of organisms can change over time was first thought about and later published by the famous English naturalist, Charles Darwin in 1859. He wrote a book called “On the Origin of Species”, which continued to highlight views such as …
Homeostasis is the control of internal conditions, be it temperature, specific blood conditions or other variables within living organisms. The term ‘Homeostasis’ was first defined by the French physiologist, Claude Bernard, in 1865. The purpose of homeostasis is to provide a consistent internal environment for set processes to occur. Each process, or reaction, has a …
