Which of the following substances typically moves either k7 -z :z2hu:q*vc( nxchken(ain or out of a leaf's inne(72 a(kzqnhe x h*cuz-n: k:cvr air space via stomata?
I. Water
II. Oxygen
III. Mineral ions

  The diagram below shows a potomq(8qd 2s7 +*brjrknkieter which is used to measure water uptake in plantski rsk+b qr 8(2*jndq7.


A plant cutting was placed in the potometer as shown above. What changes would be observed after a few hours?

  How do different muscles contribute to thd;e9 d r+n.vg+xzre6ti;: ddr e decrease in air pressure inside the lungs+r+g ve.6ire9d ; xr z;:dtndd, causing inhalation?

  Which of the following takes pi n7xki 9*n;vufsbh3 b49q*teli )fv .lace during exhalation?
I. The diaphragm forms a dome shape
II. Internal intercostal muscles contract
III. Pressure increases inside the thorax

  Air is carried to the lungs by entering through the no 3 m*d kkg1j7s b3efdyak(y)ij1x)5,kwzep o)strils into the nasal cavity, and then as shown in th73d1mk1) 5ky(g)p)if y ee j3d,zoa*k wsjkbxe pathway below.



Which of the following statements are correct descriptions of structures P and Q?

  The diagram shows an apparatus used to investigate the rate of tran7b *.mk-sxic ziu 4gs:spiration in plants. 4:*gi ixc-7umsz.skb


1.Name this piece of apparatus.
This piece of equipment is a   .
2.Describe the relationship between rate of transpiration and the movement of the bubble.

This table shows data collected by a student when they used the piece of apparatus in (a) to investigate the effect of temperature on the rate of photosynthesis.


1.Describe, using the data provided, the relationship between temperature and the rate of water uptake.

2.Explain the change in water uptake from 20 $^{circ}$C to 35 $^{circ}$C.

3.Suggest a reason for the lower rate of transpiration at 40 $^{circ}$C.
At 40 $^{circ}$C    are closed to conserve water.

The micrograph shows a transverse section through a dr 8ymm8fa u j/ec+7h0wicot stem.


1.Label xylem tissue with an ‘X’ in the micrograph above.

2.Identify the feature that you used to identify the xylem vessel that you labelled in (a).

3.Explain adaptations of xylem for its function.

  Ventilation is important in maintaining the concentration gradients of oxygeuf7 n .,l//odljp2k(ly4jpw7 yc4qkhn and carbon dioxide between the air in the hllky24c/4o/w p.,jlqn fup7 y(jdk 7 alveoli and blood flowing in adjacent capillaries.

Which of the following shows the correct concentration gradients when the diffusion of gases is taking place?

1.Describe one characteristic of thp:ejuc,;x 2 (i9.jyfevo ,r lze bronchioles.

2.Distinguish between the external intercostal muscles and the internal intercostal muscles.

3.Outline how the concentration gradients of oxygen and carbon dioxide are maintained in the lungs.

  What is the main factor that causes the pressure inside xylem vez1f .cqi:-z yossels to be lower than atmospher.zcq1 yo:fiz- ic pressure?

Ventilation and lung structure play important roles in gas exchang t8 3f+jz-uife i, 9h;iil2ppse which is needed for cfzt2i8;i,ef 9s3 + p-iilj hupellular respiration.
1.State one possible cause of emphysema and outline the symptoms of the disease.

2.Describe the lungs of an emphysema patient.

3.Explain how muscles bring about pressure changes in the thorax during ventilation.

  Strawberries are a popular fruit sold around the5n g(g0,ajwux n ihd/qdf0u,p 1i q(s1 world. However, despite their popularity, their retail value, like many other fruits, is based on their quality, which can be negatively impacted by factors which affect them before and aftea gq js iud0in5/(,q1d(hpu nf0w1gx,r harvest.
A study was conducted which looked at the factors behind two common conditions in strawberries, water soaking and shrivelling, both of which can have severe impacts on the quality of fruits.
The graphs below show the result of an experiment which investigated the rate of water uptake by strawberries before harvest and the rate of transpiration after harvest in relation to the surface area of the fruit.


1.1.Compare and contrast the rates of water uptake and transpiration in strawberries.

1.2.Suggest a reason for the discrepancy between the rate of water uptake and the rate of transpiration.

2.Calculate the surface area (cm$^2$) which would result in the uptake of 500 mg of water in two hours.
Surface area=  cm$^2$
3.State the tissue through which water is transported in plants.
In plants, water is transported in the   .
In an attempt to reduce the volume of water uptake in strawberries, scientists tested the effect of incubating them in different isotonic solutions, which contained solutes of varying molecular weights. The results of the experiment are shown below.



4.State the term used to describe the movement of water molecules into and out of plant cells.

5.1.Identify the incubation solution which resulted in the lowest uptake of water in strawberries.

5.2.Describe the relationship between water uptake and the molecular mass of solutes in the incubation solution.

5.3.Predict the uptake for strawberries incubated in a solution containing PEG6000 if they were incubated for 2 hours.
The uptake at two hours would be around   mg.

Despite the influence of environmental factors on the quality of strawberries before and after harvest, genetic factors were also attributed to important retail characteristics, such as the colour of strawberries.
In the experiment below, 40 Redlands Joy strawberry plants were pollinated in the following four ways:
Autogamy (natural pollination with pollen from the same flower)
Self (hand pollinated with pollen from the same plant)
Sugarbaby (hand pollinated with pollen from the sugarbaby variety)
Rubygem (hand pollinated with pollen from the Rubygem variety)
The brightness, redness and yellowness of the fruits produced from each plant was recorded.


6.Calculate as a percentage, to the nearest whole number, how much brighter the brightest strawberries were, compared to the dullest strawberries. the percentage=  %

7.Describe the effect of different pollination treatments on the colour of strawberries.

8.Discuss whether the data provided supports the hypothesis that cross-pollinated strawberry flowers produce strawberries with a higher retail value than self-pollinated strawberry flowers.

  The image below compares the morr65nrf 4-kcr ftality rate for smokers and non-smokers over the k4 r rcf-n56frage of 40.

  How can tobacco smoke cause breathing dia,.cyf/twft1 pi) **qt at or)fficulties in smokers?

The image shows oxygen dissociation curves for an adult with sickle cell anabk2 g9n5 /wkp(czld)wemia and an adult without sickle cell anaemia. Sickle cell anaemia is a genetic disease caused by a point mutation in the gene coding for haemoglobinpd9/kgn5)k( l2w bwzc, resulting in the substitution of a single amino acid in the haemoglobin molecule.


1.1.Identify which oxygen dissociation curve represents a person who has sickle cell anaemia.

1.2.Explain a reason for your answer to part (i).

2.Explain how the structure of normal haemoglobin enables cooperative binding.

3.1.Draw a curve on the graph that represents the oxygen saturation of foetal haemoglobin at different partial pressures of oxygen.

3.2.Some people with sickle cell anaemia continue to express foetal haemoglobin into adulthood, a phenomenon known as foetal haemoglobin persistence. Suggest why people with sickle cell anaemia, who express foetal haemoglobin into adulthood, have less severe symptoms of sickle cell anaemia than those who switch to adult haemoglobin.

4.Explain how intense exercise causes changes to the affinity of haemoglobin for oxygen.

  The photograph below shows a zba--nbm zcyg r 27kv7, 5aiv,xerophyte which can live in extreme environments.



1.State the process which accounts for the majority of water loss in plants.
The process is   .

2.Distinguish between the environments where halophytes and xerophytes live.

3.Outline the adaptations of xerophytes which enable them to survive in extreme environmental conditions.

Lung volumes and ventilation rates can be measured using a spiromelvan 8s( bt24lter. During a school lab a student was asked to breathe normally at rest, then they were asked to take the deepest breath in that they could, followed by the largest breath out, before returning to breathing normally at rest. Below is the trace for this studen4a8v2 n (tlblst.


1.Calculate the total volume of air inhaled and exhaled during one minute by this student when breathing normally at rest.

Below is a diagram of the spirometer used by the students. The subject puts on a nose clip, to prevent air from escaping through the nose, and breathes in and out through the mouthpiece. The chamber is closed so the volume of air with each inhalation and exhalation can be recorded on the drum trace. The chamber is opened between trials to allow the air to refresh and the trace to be recalibrated.


2.Explain why the trace decreased in height during the 100 seconds.

3.Suggest a possible investigation that could be conducted using the spirometer.

4.State two variables that must be controlled in the investigation you suggested in part (c).
Another student, who played the flute regularly, was then asked to record their results to compare them to student 1, who did not play a wind instrument. The trace for this second student is shown below.

5.Discuss whether the data in the two graphs support the hypothesis that playing a wind instrument increases lung volume.

  A spirometer is an apparatus that measures skx/j cnff6, n8i.jd siun-,,the volume of air (dm$^3$ ) inhaled and exhaled over a period of time. The graph below shows the spirometer reading of an individual after exercise.

What would the spirometer reading look like for an individual at rest who has not recently exercised?

  During ventilation, arep a)op6l 5x9ir from the atmosphere enters the lungs. Lungs consist of alveoli which lack muscular p9 o 6)peaxlr5tissue. The lungs are attached to the ribcage through the pleural membranes which are filled with a fluid with a constant volume.

What would be the most likely consequence if there was a puncture in the ribcage exposing the lungs?

Gas exchange is very important for both plants fe(z;mos n)* ,h+uy eaand animals.
1.Outline the properties of gas-exchange surfaces.

2.Describe how muscles bring about pressure changes during inspiration in humans.

3.Transpiration is a result of gas exchange in plants. Explain how different environmental factors affect the rate of transpiration.

Plants transport water from the roots to the leaves to replace w-*:v2tne8ie8g ) b:qyuorh wv ater lost by evaporv eynqiwhob8) : e:8ur* -vgt2ation.
1.Outline the structural changes in the xylem vessels as they mature from primary to secondary xylem.

2.Describe the movement of water in plants beginning with water in the soil and ending with water vapour in the atmosphere.

3.Explain how different environmental factors affect the rate of transpiration.

  The photograph below shows lungs that have undergonedz2 +lqm lwvj35yl 9;p excessive breakdown of alveoli by protein-digesting enzymes (part on the left) compared to normdllv 2zj93m;wly+5qp al lung tissue (on the right).

Which of the following are not symptoms of the lung condition pictured above?

  The diagram below shows a simple apparatd 9(za+nuvf 1 8-n;f e,r7k3bgctfkfpus which uses a porous pot to model water transport in plants.rc31-e k f( u9,g7d;zvfnkpfb n+t8fa

Why is a porous pot used to model water transport in the xylem?