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Thats what i thought.Buiboi said:ADH is responsible for increasing the permeablity of the collecting ducts of the nephron in absorbing water..so ADH increases for sure
aldosterone increases the reabsorption of salts, hwoever, salts as in the absoroption of sodium ions and getting rid of potassium, and sodium ions is responsible for water retention. so if he was to dehydrate, he would need to have an increase in aldosterone to retain the water he currently has and increase water concentrations with more adh, so they work hand in hand, also addisons disease is the disruption of the adrenal cortex, which means not enough aldosterone is produced and a consequence of the addisons disease is severe dehydration so.... yeah thast what i believe
when ur dehydrated its specifically talking about water. ok ill tackle this from another perspectivegaj said:the person just ran a marathon, im pretty sure their is no one that doesn't sweat after running a marathon. it is true that aldosterone acts on increaseing sodium reabsorbtion, but this is too maintain blood pressure. someone who is dehydrated will hjave low bp and the increased reabsorbtion of sodium causes an increase in water osmosi, thus increaseing bp
hoca pontis said:alright, here they are...you better appreciate it coz i typed it all up...lol
Q 1) the diagram shows one example of enzyme action as demonstrated by the 'Lock and Key' model.
Which part of the diagram represents the substrate?
(A) C
(B) ACB
(C) AB
(D) A B
(use your imagination to remember the picture)
Q 2) why do cells contain many different enzymes?
(A) Enzymes are timperature specific
(B) Enzymes are specific in their action
(C) Enzymes are sensitive to pH changes
(D) Enzymes are sensitive to substrate concentration
Q 3) This is a longitudinal section of a plant stem (x 200)
What is the name and function of the tissure labelled W?
(A) Xylem- Transports water and mineral ions
(B) Phloem- Transports water and mineral ions
(C) Xylem - Transports simple sugars
(D) Phloem - Transports simple sugars
Q4 ) The Wollemi Pine is easily killed by the fungus which lives in the soil. The last small population of Wollemi Pines grows in a remote part of a national park in NSW. Scientists studying this natural population use strategies to prevent the trees becoming infected.
Which procedure would be most effective in preventing the spread of this fungus to the Wollemi Pines?
(A) Inspecting soil smaples in the area
(B) Commercially producing and distributing the Wollemi Pine
(C) Washing soil from the scientists' shoes before they walk in the area
(D) Preventing the importation of infected Wollemi Pines into Australia
Q 5) Students performed an investigation to compare the effectiveness of two water treatments for purifying pond water.
Three samples of pond water, A, B and C, were collected and each used to inoculate the agar plates. The plates were incubated at 25 degrees and examined 3 days later. The number of visible bacterial colonies on each plate was counted an dthe result tabulated.
What is the dependent variablein this investigation?
(A) the use of a control sample
(B) the number of visible bacterial colonies
(C) the use of sterile agar plates for each sample
(D) treating the water by boiling or adding pool chlorine.
Q 6) Which biological term is best described by 'engulfing and destruction of bacteria or other foreign bodies'?
(A) vaccination
(B) phagocytosis
(C) antibody production
(D) an inflammation response
Q 7) Which leaf structures are adaptations to assist in the conservation of water?
(A) central vein, irregular leaf shape
(B) large air spaces, pointed leaf tip
(C) spongy mesophyll, vascular bundle
(D) sunken stomates, thick waxy cuticle
Q8) Which observation can be used to demonstrate Koch's contribution to understanding the cause of disease?
(A) polio vaccinations trigger an immune response
(B) some mosquitoes carry a pathogen that is often fatal to people
(C) a lack of vitamin C is found in all people suffering the nutritional disease scurvy
(D) the bacteria, Heliobacter pylori, is present in the stomach of all diagnosed with stomach ulcers.
Q 9) Current reproductive techniques can be used to alter the genetic composition of a population. Some of these methods were also used in the nineteenth century by Gregor Mendel.
How did Mendel use reproductive techniques in his experiments?
(A) he artificially inseminated the pea kplants to achieve wrinkled seeds
(B) he cloned the pea plants with round seeds to increase their food supply
(C) he created a transgenic species by mixing tall pea plants and short pea plants
(D) he artificialy pollinated the pea plants to test for different genotypes in the offspring
Q10) Which statement best describes the relationship between proteins and polypeptides?
(A) proteins are composed of polypeptides
(B) polypeptides are composed of proteins
(C) proteins, unlike polypeptides, are composed of amino acids
(D) polypeptides, unlike proteins, are composed of amino acids
Q11) The family tree shows the inheritance of a genetic characteristic.
What is the probability that a daugter of parents A and B would be affected?
(A) 0%
(B) 25%
(C) 50%
(D) 100%
(use your memory to picture the diagram..)
Q12) Which flowchart correctly shows an interaction betwen B and T lymphocytes during an immune response?
(A) infection --> T cells recognise antigen as foreign --> B cells stimulated and antibodes produced
(B) infection --> B cells recognise antigen as foreign --> T cells stimulated and antibodies produced
(C) infection --> T cells stimulated and antibodies produced & B cells recognise antigen as foreign
(D) infection --->B cells stimulated and antibodes produced & T cells recognise antigen as foreign
Q13) The effectiveness of new insecticide was tested on a large population of mosquitoes over a number of breeding cycles. At first the population of mosquitoes was reduced dramatically by the use of the insecticide. after a number of breeding cycles the population then began to increase until the insecticide appeared to have little effect.
How would the Darwin/ Wallace theory of evolution by natural selection explain these observations?
(A) some of the original population were isolated from the insecticide as a control group
(B) some of the original population had already reproduced before the insecticide was used
(C) some of the original population were resistant to the insecticide and passed this on to their offspring
(D) some of the original population adapted to the insecticide and survived to produce offspring
Q14) At the end of a marathon race a runner's body is dehydrated.
How does the body control the two hormoes, ADH and aldosterone, to help to re-establish normal water balance?
(A) ADH is released and aldosterone is inhibited
(B) ADH is inhibited and aldosterone is released
(C) both ADH and aldosterone are released
(D) both ADH and aldosterone are inhibited
Q15) How have Walter Sutton and Theodor Boveri contributed to the understanding of inheritance?
(A) by determining the structure of DNA
(B) by improving knowledge of sex linkage
(C) by demonstrating teh effect of environment on phenotype
(D) by identifying the importance of chromosomes in inheritance
Nope, question 1 is definitely not (A); its (D). An enzyme is defined as a catalyst which aids in speeding the process BUT it doesn't take part in the reaction. Molecule C is the enzyme because it brings subtrates "A and B" together, to form a product AB. Then, molecule C leaves the productAB to catalayse other reactions. Molecule C didn't take part in the reaction, thus it can't be the substrate. A and B are the substrateselliegow said:I am almost certain Question 1 was (A).
I dont know the exact question...
But I think it asked which was the substrate
All the other pictures were either the enzyme or the enzyme and the subtrate together, (A) was the only one with just a substrate.
Or I could be completely wrong!
Did anyone else find the test ridiculously easy? ...stoked! XD
lol, you just contradicted yourself. In this key source, it said products are the substances that the substrates become; meaning, that the substrates 'can be joined' to become the product. Therefore, AB are the products which the substrates become, thus (C) is wrong since (C) shows the products; therefore A and B have to be the substrates; thus (D) is the correct answer.Stipe Pletikosa said:Question 1 is officialy C
As extracted from a key source:
'The Products are the substances that the Substrate(s) become. One substrate can be split, or two substrates can be joined'
In this case it was 2 substrates joining. You cant just ignore the arrows in the diagram! They showed the flow of the reaction.
What are you talking about.sslions said:lol, you just contradicted yourself. In this key source, it said products are the substances that the substrates become; meaning, that the substrates 'can be joined' to become the product. Therefore, AB are the products which the substrates become, thus (C) is wrong since (C) shows the products; therefore A and B have to be the substrates; thus (D) is the correct answer.
holy cow i think youre rightmithril1337 said:
there for A is the correct answer since the statement is true.
Lols please disprove me this is what a friend said.....