AQA Additional Biology part 2 use this in conjunction with your revision guide Enzymes
Substances in plants and animals that speed biochemical reactions are called enzymes. Enzymes can build up or break down other molecules. The molecules they act on are called substrates. Enzymes are catalystschemicals that hasten a chemical reaction without undergoing any change themselves.
Enzymes Enzymes and temperature
Enzymes and pH Bakers yeast use enzymes Digestive system
Digestive enzymes and bile enzymes in industry
Fermentation Fermentation Fermentation is when a cell uses sugar for energy without using oxygen at the
same time. Yeast is an organism that ferments. When yeast ferments sugar, the yeast eats sugar and makes alcohol. Other cells make vinegar or lactic acid when they ferment sugar. When yeast ferments, it breaks down the glucose (C6H12O6) into ethanol
(CH3CH2OH) and carbon dioxide (CO2). Ethanol fermentation always produces ethanol and carbon dioxide. It is important in bread-making, brewing, and wine-making. Lactic acid fermentation produces lactic acid. It happens in muscles of animals when they need lots of energy fast.
Homeostasis Homeostasis (homeo meaning "same" and stasis meaning "condition") is when an organism keeps its bodily conditions (pH, temperature, amount of oxygen or carbon dioxide in the blood, for example) in a stable condition. It does so by regulating its inner equilibrium. In
living things, the study of how they keep in a stable condition if called physiology. Examples of homeostasis: The regulation of water and minerals in the body. The regulation of body temperature. This is done by sweating to cool off and shivering to warm up.
In mammals, the main organs involved with homeostasis are: The hypothalamus and pituitary gland the lungs the skin the muscles
the kidneys the liver and pancreas Homeostasis
Temperature Homeostasis water balance Diabetes
Insulin Glucose - homeostasis
Mini test Put these in order Chromosomes Add their meaning
Unit of information Genome Collection of information
units Gene All of the information units
for an organism DNA The code for the information
Method of Inheritance Alphabet (a,b,c,d,e,..) DNA (building blocks)
Sentence (You will be able to roll your tongue.) Gene
(unit of information) Chapter of a book (full of sentences)
Chromosome (a stack of genes) Book (all the sentences all the chapters)
Genome (all the genes all the chromosomes) Gene
DNA DNA
Chromosomes Asexual reproduction Mitosis
Google Mitosis animation mitosis on the run Mitosis chromosomes replicate then cell divides
DNA Replication Mitosis 2 Daughter cells
B A C
E G
Put them in the right order D F
Inheritance mitosis Stem Cells
Harvesting a stem cell Undifferentiated cells Human regeneration
Humans can only regenerate If existing cells are still there We are not able to Regenerate whole
limbs But what if we could? MEIOSIS
Gametes sex cells (egg cell/sperm) Meiosis
Pick two parents list for each skin colour, hair colour, straight/curly hair, eye colour, face shape. Make (list/draw) an offspring Variation
Inheritance of sex Key Words
Genotype Homozygous Homologous Alleles Dominant
Phenotype Hertrozygous Recessive
(co-dominance) Alleles
Dominant alleles hetrozygous or homozygous Recessive alleles homozygous alleles
examples
Dominant Freckles F Dark hair H
Tongue rollers T Free ear lobe E Recessive no freckles f
light hair h non-tongue rollers t ear lobe joined e Do punnett square crosses
give ratio of possible genotype and phenotype of offspring Father is hetrozygous for freckles, mother homozygous for no freckles Father homozygous for dark hair mother
homozygous for light hair Father hetrozygous for tongue rolling, mother hertozygous for tongue rolling Genetic Disorders
Huntingtons disease is a disorder of the nervous system caused by a dominant allele of a gene and can therefore be passed on by only one parent who has the disorder Cystic fibrosis must be inherited from both parents. The parents may be carriers of the disorder without having
the disorder themselves. It is caused by a recessive allele of a gene and can therefore be passed on by parents that do not have the disorder Embryos can be screened for alleles of these and other disorders
Genetic family trees Consult your partner and assess the probability of these genetic
disorders being passed on to the children In Books Work out the probability of genetic disorders being passed on
Produce a report for the family of William has huntingtons disease what is the probability of Kristi getting huntingtons Show David and Jessica how you came to that conclusion Both Mary and Peter are carriers of the CF gene advise
them of the probability of their children getting cystic fibrosis Explain to them how you calculated the probability Anne has CF and is thinking about getting married and starting a family what advice would you give her?
