题序 一 二 三 四1 四2 四3 四4 四（56） 总 分
Part 1: Explain terms (Select 8 terms from followings5 marks for each and total
1. Root pressure
Root pressure is a power which pushes water to mount along vessel, depending on
physiological activity of root.
2. Critical period of nutrition
A period during which plant is most sensitive to nutrition deficiency and is most easily
injured by this, but the nutrition requirement is not always largest at that period.
3. Cpathway 3
It is referred as a photosynthetic pathway in which the initial product of photosynthesis in
CO fixation is Ccompound. 23
4. Cyclic electron transport
A kind of photosynthetic electron transport around PSI in which the excited electron
starts to transport from PSI to several electron carriers such as Fd, PQ, Cytbf and PC and
return to PSI. The transport only generate a supplementary of ATP.
5. Cytochrome oxidase
Cytochrome oxidase is one of a superfamily of proteins which act as the terminal enzymes of
respiratory chains. The enzymes are vectorially arranged so as to transfer charge across the
membrane as electrons are passed to O. The electrogenic process is contributed by vectorial 2+electron transfer, and the uptake of H on reduction of O. 26. Transfer cell
Transfer cells are specialized companion cells that have an increased surface area, due to
infolding of the plasma membrane. They extensively exist in source or sink organs and
facilitate the transport of assimilate from apoplast (cell space) into phloem or inversely.
7. Growth inhibitors
The synthetic compounds resistant to GAs in function and inhibit the growth of the
subapical meristem. The inhibitory effect can be reversed by GA, but not by IAA.
One kind of micropigments in plant which can receive the signal of light such as the
direction and intensity of light, magnifying the signal, as a result, and the plant will make
corresponding reaction. They are photochrome, cryptochrome or blue/UV-A receptor and
9. Short-day plant
The plant can only flower under daylength shorter than its critical day length of 24 h cycle.
Such as morning glory, cocklebur, chrysanthemums, tobacco, late soybean, late rice and late
10. Physiological drought
One kind of drought happens in plant body. It is referred to all phenomena that make plant
body water imbalance because water absorption is less than water loss in plant body. Air or
soil drought, salty and chilling or heat injury etc often cause physiological drought of plant.
Part 2: QestionsTotal 60 marks. 1234 are necessary to answer and chose one
of 5 and 6.
1Why does low temperature make plant decease in water absorption 7 Marks
At low temperature, water can not easily diffuse into cell as water and plasma viscosity increase
and water conductance decreases；The active absorption depending on ATP decreases because respiration lowers; Less area for water absorption is due to slower root growth and poor root hair
2Describe steps of nutrient movement from bulk soil to root surface and across membrane.
The nutrient movement from bulk soil to root surface involves interception and ion exchange,
diffusion, mass flow and the nutrient uptake cross membrane carries out through passive transport
(simple diffusion, facilitated diffusion (carrier and ion channel) and active transport by ion’s carrier or/and pumps.
3Introduction to relationship between plant hormones and plant flower formation10
Most of plant hormones can influence plant flower formation. GA and Eth are well known
plant hormones which regulate flowering. GA can promoting bolting and flowering instead of
low temperature and long daytime and enhance male flower initiation of cucumber but female
flower initiation in a lot of tree. Eth can promote male flower initiation of many kinds of plants,
especially for cucumber, pumpkin etc. IAA also enhances male flower initiation and flowering due
to induction of Eth.
4How to keep the fresh fruits, vegetables and store the dry seeds longer in basis on
principle of respiration?15 Marks
High respiratory rates of fresh fruits, vegetables and the dry seeds will consume more stored
organic nutrition of them. Therefore it is most important for them to reduce the respiratory rate
during the storage periods. The respiratory rate can be greatly impaired by microorganism,
environmental conditions and inner ethylene concentration. If you want to store them longer,
following things should be done.
When keep the fresh fruits, vegetables longer, you choose no wounded ones at first; then you
keep it at lower temperature, but a bit of higher than cold injury temperature; third, you control the
gas components, higher CO
and lower O, still but higher than exhausting point; Fourth, you 22remove Eth by suitable ventilation or you use gene modification (transgenic plant)-------anti ACC
synthase to protect fruit repine like tomato
When keep the seed and food longer, you fully dry the seeds and control the seed water
content below safety water content, in which seed can be stored one cycle year or do
seed-ultradried storage ; you can lower food temperature to -4 ~4 ?, even super-low temperature storage（-193?）; And you regulate gas components by filling with N, COor autonomously 22 decrease in O by respiration as well as you use the chemicals to kill the microbe or insects. 2
5What does greenhouse effect impact to plant growth and development21 Marks The greenhouse effect is due to increased emissions of COand CH, which made the short-wave 2 4of solar radiation conducted through the atmosphere while the infrared radiation come back to the
Earth's surface by reflection, so atmospheric temperature increased. CO and temperature is the 2greatest impact on the flower and plant photosynthesis.
According photosynthetic pathway different plants can be divided into C, C and CAM. 34Generally believed that increased CO concentration will increase the net photosynthetic rate on 2
C plants, but in high temperature areas，high temperature will increase light respiration and dark 3
respiration, resulting in net photosynthetic rate reduction. However, in most areas, increased
accumulation will accelerate growth.C plants need vernalization to blossoming; a rise in 3
temperature in this part will affect plant propagation.
Recently, many studies show that long-term increased CO concentration in plant will lead to 2
photosynthesis down, so the problem is more complex. On C plants, the concentration of 4atmospheric CO has reached the saturation point, a rise in CO concentrations cannot lead to 22increased photosynthesis and accelerated growth, but the high temperature will increase
respiration, it gives rise to negative growth. This tends to a disadvantageous position while
compete with C plants, having the potential to reduce the population. On the CAM plants, an 3
increase in CO concentration will increase its absorption of CO at night, improving the 22photosynthesis during the day.
Because of the greenhouse effect may also cause drought, so the impact of different plants’
photosynthesis means no conclusion has been drawn. Under present knowledge, there is not
enough time to study some of the conclusions and conjecture, it need further study.
6What should we provide the plant for growth better in facility culture21 Marks
The plant is affected by lots of environmental conditions such as light intensity,
temperature, soil moisture, nutrition concentration and abiotic stresses etc.
In facility culture we should provide the plants sufficient light intensity and light quality
by covering with transparent material which can even pass through a part of UV in order to
photosynthesize and prevent the plant overgrowth. We should control the temperature to
about growth suboptimum and the larger difference in temperature between day and night
(about 10 ? higher in daytime than at night ) and ventilate in order to provide enough CO 2in the facility. We should keep the soil or substrate moisture neither too wet nor too dry and
provide enough all essential elements to plant. If the plants are cultured with hydroponics, it
is necessary to use flow culture or airing. If the plants are cultured in the soil directly, it is
necessary to prevent soil from salty. We should shower the soil for other several seasons to
avoid salt stress.
In facility culture pests and diseases often break out and make harmful to plants, we
should carefully deal with them by using pesticides which can kill the pests or pathogens but
safe to human beings. Sometime we should breed special insects to help plant pollination
and use plant hormone for promotion of setting.