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- a) The left ventricle releases a high amount of pressure approximately 15kPa in just under half a second whereas the right ventricle only releases a low amount of pressure approximately 5kPa in just under half a second. The left ventricle was at the same pressure of the aorta. The right ventricle is much slower at releasing pressure unlike the left ventricle. It took both ventricles left and right was both stationary after half a second and the pressure picked up again.
c) When blood is pushed into the ventricles by the contraction of the atrium, and then the atrium relaxes. Next the ventricles contract this contraction is forceful, the high pressure forces the blood into the aorta this causes a pulse in the arteries all over the body.
As the climbers went higher in altitude the mean concentration of haemoglobin increased. For example at 1000 altitude the concentration of haemoglobin was 12.5 [JO2]whereas at 4600 altitude the concentration
oghaemoglobin was 18.2[JO3].
a) Because lamb and pork already have a higher fat content than beef and chicken. For example fatty lamb and pork have 72g and 71g of fat whereas fatty beef and chicken have 67g and 5g.
b) Because foods such as fish, fish oils, eggs and dairy products have a higher content of vitamin D than lean meat.
c) Lean pork originally has less fat content and but not less than chicken
- Basal metabolic rate is the amount of energy required to maintain brain function and the rest of the body’s basic metabolism.
- a) (i) minimum body mass: 61kg
Maximum body mass: 74kg
(ii) It shows the boundaries between being underweight, normal and overweight.
b) (i) women with the body mass between 39kg and 65 kg are fat than men[JO4]. Men that have a body mass of 33kg to 55kg have more skeletal muscle than women. Fewer women have lean muscle than men. Men have more a skeleton body mass than women.
(ii) Everyone is different
b) Measurement of temperature
9. a) nicotine and carbon monoxide in the tobacco smoke damage the cardiovascular system .
b) By having a balanced diet and exercising regularly
b) Because when both smokers and non-smokers cholesterol level increased over the years both groups had heart attacks. Basically the non-smokers didn’t have to smoke to increase their blood cholesterol level there many other causes of heart attacks.
c) For smokers the main cause for high cholesterol is smoking whereas for non-smokers there are many other reasons such as an unhealthy diet.
d) When the carbon atoms are combined together by single bonds.
11. H2O, hydrogen, source, specific heat capacity,
12. a) a hydrogen bond
b) Because they are not polar
c) It is important because the water stays at a constant temperature for all the organisms.
13. Polymers, helix, hydrogen
14. a) A= head B= tail
b) Fatty acid
c) Condensation reaction
15. Blue to red, water, biuret
16. There are various risk factors for CHD one being age, the risk of CHD increases with age, over 80% of people who lost their lives to CHD are over 65 years old for example the development of atherosclerosis. Atherosclerosis is when the arterial walls thicken and lose elasticity.
Another risk is genetics which include ethnicity and hereditary factors for example if the parents have CHD then the children are most likely to develop it themselves in later life.
Smoking is another risk it damages the cardiovascular system by reducing the ability of red blood cells to transport oxygen. Nicotine stimulates adrenaline production which increases heart rate and causes the arteries to contract and raises blood pressure.
Alcohol in excess leads to high blood pressure levels and damage to heart and vessels.
High cholesterol levels lead to CHD. The cholesterol in the blood block receptors in cell membranes that metabolise lipids this leads to plaque on artery walls.
17. Quantitative research means the measurement of everything in an experiment and qualitative research means the understanding of the experiments on how everything works.
AS UNIT 1: TOPIC 2 Assignment B (TMA)
- There are many factors affecting enzyme activity one of them being temperature, enzymes have a specific temperature at which the work the quickest. For example for human enzymes its 37oC.
The pH scale is another factor, enzymes work more quickly and efficiently at a specific pH, for example for most enzymes this is pH 7-8.
Also there is enzyme concentration, when the concentration increases the rate of the reaction increases. Normally enzymes in cells are present in low concentrations.
Another factor is inhibitors this reduces the rate of reaction there are two types of inhibitors, a competitive inhibitor and a non-competitive inhibitor.
Substrate concentration also affects enzyme activity because when substrate concentration increases the rate of reaction increase as well.
protein, active site, temperature, increase
a) Osmosis is a special case of diffusion. It’s where water molecules can diffuse without difficulty through a cell membrane, whereas for other molecules it difficult for liquids to pass through it.
b) Facilitated diffusion is the transport of substances across a membrane by a trans-membrane protein molecule.
- a)(i) I don’t know
b) i) I don’t know
ii) To diffuse into the ribosome and attach to mRNA
- a) The difference between the term gene and allele is that gene is a section of DNA whereas an allele is a version of a gene.
b) i) person 1
Person 4: heterozygous
Person 5: heterozygous
Person 6: homozygous
- The surface is thin; the walls of the alveoli are made of a single layer of flattened epithelial cells so the gases just need to diffuse through 2 thin cells and the alveoli is constantly moist because water diffuses from the alveoli cells into the alveoli. Basically there is 2 ways that maintain the concentration gradient there is blood flow on one side and air flow on the other.
- a) Meiosis has occurred reason being because when meiosis occurs the cell divides in to four separate cells.
b) Because when each cell is formed they each have half the chromosome number.
c) In the sperm
- The cell membrane surrounds all living cells, one of its functions are it controls how substances move in and out of the cell. Cell membrane is made of phospholipids, proteins and carbohydrates arranged in a mosaic structure. The phospholipids are arranged in a bi-layer meaning their heads facing outwards and the tails facing each other in the middle of the bi-layer. The heads are polar hydrophobic meaning they are water loving and the tails are hydrophobic fatty acids meaning their water hating. The phospholipids strengthen the membrane.
The proteins usually go from one side to the other of the phospholipids bi-layer and can also sit on the surface. The function of the proteins in the membranes are usually involved in transporting substances across the membrane, also the proteins on the outside surface act as receptors having specific binding site where hormones and other chemicals can bind.
The carbohydrates found on the outer surface and are attached to the membrane proteins. The carbohydrates are made of a variety of monosaccharide and form glycocalyx outside the membrane. The glycocalyx is involved in cell protection and cell recognition and antigens.
The cell membrane holds all of the cells content together.
- DNA is double-stranded it has two polynucleotide strands alongside each other. The strands are anti-parallel so they run in the opposite direction. The two strands are wound around each other to form a double-helix, joined together by hydrogen bonds between the bases. The bases are in pairs Adenine is with Thymine and Cytosine is with Guanine. DNA replication means that DNA with all its genes must be copied every time a cell divides. When the DNA is being copied the double helix unzips and two new strands are built up by the base pairing onto the tow old strands, DNA replication can take a few hours.
- a) Because only two people from the third generation have the condition it is recessive if it was dominant the condition would’ve been inherited through all three generations.
b) i) 0.043032
ii) That both parents have the condition and it mostly likely their offspring will have the condition.
c) They take a genetic screening where they are tested if they carry any specific conditions and diseases.
11. a) stage 1: transcription
Stage 2: translation
b) In the DNA
c) tRNA molecule collects amino acids
[JO1]Is this really acceptable scientific explanation and terminology?
[JO3]Units please – 18.2 what?!
[JO4]Re-read answers please.