Suggest why it was not appropriate to estimate the number of Jaguars using the capture-recapture technique (2)
Esitmate will be inaccurate because it is a low number.
Most studies estimate the population density of Jaguars South American rainforestto be 5 individuals per 100km2.
9/271 = 0.03 Jaguars per km2 therefore 3 jaguars per 100 km2.
Other evidence used to estimate the jaguar population includes footprints and reports of sightings by local humans?
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Human sightings – seeing the same individual twice
Explain why the Madidi National Park is an example of conservation rather than preservation. (3)
Conservation because there are local people there and its for sustainable use and that area is used for logging.
Calculate the approximate area under the curve, between day 35 and day 98 for clone C. (3)
Area of triangle = 700
Calculate the area under the curve for clone C as a proportion of the area under the curve for clone B. (1)
76/100 = 0.76
The clones were planted in adjacent fields in order to control variables such as temperature, wind speed and rainfall.
Light intensity and soil pH.
State two other structural similarities between lactose and maltose. (2)
Two 6 membered ring.
Differences between lactose and maltose (3)
Lactose has beta 1-4 glycosidic bond but maltose has alpha 1-4 glycosidic bonds.
Explain how the structure of galactose allows it to be used as a respiratory substrate. (3)
Bonds contain energy which are broken by respiratory enzymes.
Suggest and explain why lactose is unable to cross membranes. (2)
Too big and unable to pass between phospholipids.
Lactose is a reducing sugar.
Set colorimeter to zero and use a red filter. Then use known concentration of lactose to produce serial dilutions. Also construct a calibration curve and to test unknown sample and read from graph to determine unknown concentration.
Calculate how much shorter than males female cheetahs are.
4.7 percent
State one way in which genetic diversity can be measured. (1)
To measure the proportion of heterozygotes.
Use the table below to identify two differences between the part labelled G and the structure of a molecule of ATP.
G contains guanine where a molecule of ATP contains adenine.
For each of the statements below, indicate whether it could be consistent with in situ conservation, ex situ conservation or preservation by instering the correct letter or letters in the table. (2)
B and C.
DNA can be obtained from a variety of plant and animal cells.
To break down the cell walls.
Suggest why a protease enzyme added in step 3 is needed to purify DNA. (1)
Because the protease breaks down the histones.
The students considered using pineapple juice as a source of protease enzyme. Suggest why this would not be an appropriate source of protease when attempting to produce a pure sample of leek DNA. (1)
Because the dna of the pineapple will mix the leek dna so its not a pure sample.
State one important step that the students had left out of their method. (1)
Forgot to mix sample with detergent which breaks down the cell membrane
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Name the process described in step 6. (1)
Precipitation.
Use fig 18 to estimate the percentage of land that is covered by woodland and forest.
15 percent.
Nitrogen cycling within ecosystems is controlled by various bacterial species. The table below lists four groups of bacterium that are involved in the nitrogen cycle.
Rhizobium = plant nodules (location).
What can you conclude from Fig. 4 about the molecules or ions that affect the functioning of the nitrogenase enzyme?
Iron and sulfur are prosthetic groups.
Put ticks in the boxes in the table to indicate whether the statements are true or false about the root cells of an onion. (2)
Contains chloroplasts = false.
Place a tick in the box next to the species most closely related to Pinus Glabra. (1)
Pinus resinosa
Explain why Pinus glabra and humans, Homo sapiens, are classified in the same domain but in different kingdoms.
Same domain because plants and humans are both eukaryotic and that they have membrane bound organelles but in different kingdoms because plants have a cell wall but animals do not.
Suggest how the scientist could achieve the following during their investigation.
Is to use a line transect e.g lay tape from edge of lake to end of field.
Calculate the total percentage decrease in the number of butterflies on farmland between 1992 and 2012.
28 percent (110-79 x 100)
Use the data given in Fig. 1 compare the changes in the number of butterflies on farmland and on woodland between 1992 and 2012. (2)
Number of farmlands stays higher than in woodlands and the number of butterflies on farmland has a smaller decrease than those in woodland.
State one variable that scientist should control when carrying out surveys such as this. (1)
Same time of year or same size of sample
State which habitat you would expect to have greater species richness and give two reasons for your answer (2)
Woodlands have a greater species richness because greater number of butterfly species are in decline than on farmland.
Female silver-washed fritillary butterflies, Argynnis paphia, are usually an orange-brown colour. However, a deep olive-green colour can be seen in some females, largely in the south of England.
Genetic biodiversity.
Explain how the students would use the calibration curve to estimate the glucose concentration of fruit juices. (2)
Find the absorbable of the juice and from the graph find the concentration that corresponds to this absorbance.
Describe how you would carry out a controlled experiment to test this hypothesis without using a colorimeter (4)
Taste the fruit juices to see how sweet.
Suggest one reason why the results for this experiment might not support the student’s hypothesis. (1)
Tasting is subjective
State two ways in which the molecular structure of cholesterol is similar to the molecular structure of glucose.
Both contain carbon atoms and oxygen atoms.
State the physical property of glucose that allows it to be easily transported in the blood stream. (1)
It’s soluble in water.
Calculate the rate of decrease in deaths from AIDS between 1995 and 1998. (2)
50-28 = 22/3 = 9.3 thousands deaths year-1
Explain the function of epithelial cells in the airways of mammals in the defence against pathogens and suggest the importance of cytoskeleton in carrying out this function. (4)
Goblet cells to secrete mucus as of a result the mucus traps the pathogens.
A student produced a summary of the stages of phagocytosis, which is shown in fig 1.1.
In stage 2 it should say foreign.
Name a piece of equipment that you could use for the random sampling of the plants shown in Table 1 (1)
Quadrat
The group of students attempted to extract and purify DNA from a plant in Upper End Meadow.
Yes
What can you conclude about the species evenness shown in the soil sample?
Low because there is a higher population of meadow ants and not many of the other species.
Suggest a barrier that makes it difficult for potyviruses to enter the sweet potato cell. (1)
Cell wall
An enzyme is involved in this process.
Phopshidester bond
Outline the action of agglutinins. (2)
Causes pathogens to aggregate together which makes it easier for phagocytes to engulf the pathogen.
Suggest how the role of the cellular component labelled B is relevant to the function of the goblet cell (2).
Contains many ribosomes for protein synthesis so more production of mucus proteins and its relevant as the function of the goblet cell helps secrete mucus.
Explain why progesterone can move across membranes. (2)
Hydrophobic and therefore not repealed by the phospholipid bilayer
Name one other molecule that can cross plasma membranes. (1)
Water
State how the structure of the cell surface membrane allows potassium ions to enter or leave a cell (1)
It has channels.
The critical value for t at the significance level of 5% with 18 degrees of freedom, is 2.10.
Answer is greater than 2.10 therefore rejected so the difference is significant.
Describe and explain the pattern of data shown on the graph as temperature increases. (3)
An increase in pigment means an increase of absorbance.
Calculate the proportion of genetic polymorphic gene loci of species B. (2)
13/32 = 0.41 (2dp)
Identify the processes occurring at A and F (2)
A = combustion.
Suggest why the concentration of CO2 in the atmosphere increases during the winter months and decreases during the summer months. (1)
Because in winter it is colder as temperature drops therefore more fossil fuels are burnt to keep ourselves warm,
Complete the table below to show the main difference in structure between glucose and starch. (3)
Glucose is soluble in water whereas starch is insoluble in water.
Describe the similarities between the nitrogen and the carbon cycle. (6)
Both the nitrogen and carbon cycle both contain decomposers.
Using the information given above, draw a conclusion about which kingdom is the most appropriate in which to classify algae.
It can’t be plantae or animalia as it said that many algae species are unicellular.
Suggest one piece of evidence not given above that could be used to provide strong support for the classification of algae in a particular kingdom. (1)
If the algae is free living
State the role of cytokines and opsonins in phagocytosis. (2)
Opsonins bind and tag to pathogens.
Use a tick to indicate below which type of immunity is functioning in a leukaemia patient when given chickenpox antibodies and explain your answer (3)
It’s artificial passive because it came from another person and that the person giving the chickenpox antibodies doesn’t create their own antibodies or T memory cells.
Which letter or letters indicate cells or structures involved in preventing the entry of pathogens into the body? (1)
C – goblet cells.
Which letter or letters indicate cells or structures that act as a physical barrier to the entry of pathogens? (1)
J – skin
Which letter or lettered indicate cells or structures that are involved in phagocytosis? (1)
H – phagosomes
Which letter or letters indicate a tissue? (1)
F – mucous membrane because they are group of cells performing a function. I.e secreting mucus. I
Describe how the ecologists should choose the number and locations of their samples to ensure that the sampling is representative.
Use stratified random sampling to have each area in its own sub category.
A student suggested that this was an example of preservation
Doesn’t contain any human interference however it wasn’t all left untouched e.g ditches were blocked to raise the water levels.
