Transport in plants

Transport in plants

1 All of the following statements are true but which one is the most precise?

Water is conducted through plant stems in

   (a) the xylem, (b) vascular bundles, (c) vessels, (d) veins.

2 Which of the following statements is the most accurate?

   (a) Food can travel up the stem in the phloem.

   (b) Food can travel down the stem in the phloem.

   (c) Food can travel up or down the stem in the phloem.

   (d) Food can travel up or down the stem in the xylem.

3 Roots have no chlorophyll and grow in darkness. So how do roots obtain their food?

4 Which of the following conditions is least likely to increase the rate of transpiration in a

plant?

   (a) a rise in temperature           (c) increased air movement

   (b) an increase in humidity      (d) increased sunlight 

5 Which of the following statements are true of transpiration

   (a) it draws water up the stem

   (b) it draws dissolved salts up the stem

   (c) it draws food up the stem 

   (d) it has a cooling effect on the leaves

   (e) it speeds up photosynthesis?

6 Osmosis and transpiration both play a part in the movement of water through a plant.

Which of these two processes makes the greater contribution to the movement of water up

the trunk of a tree?

7 Which of the following statements are true?

A potometer is an apparatus which can be used to:

   (a) measure the rate of water uptake in a shoot

   (b) measure the rate of transpiration in a shoot

   (c) measure the rate of photosynthesis in a shoot

   (d) compare rates of transpiration in different conditions

8 Most of the water taken up by a plant passes through it and is evaporated to the atmosphere. What use is made of the tiny fraction of this water which is retained by the plant?

9 A student set up a potometer in the laboratory and measured the rate of movement of water in the capillary. An average of four readings gave a rate of 50mm per minute. The apparatus was then taken outside, where there was a light breeze. Four more readings were taken without delay. The average of these readings was 130 mm per minute.

The student concluded that exposure of the shoot to rapid air movement had increased the rate of transpiration.

Criticise the design of the experiment and the student's conclusions.

Self-assessment questions                                                                                                 7.02

 

Transport in plants - continued

10 The drawing on the right represents a design for

 a potometer.

Criticise the design and practicability of the apparatus.

11 A pot plant was watered and the pot

enclosed in a plastic bag tied securely

round the base of the stem. The plant was

weighed at 9 a.m. and 4 p.m. During this

time it lost 32g in weight.

   (a) From these results, what was the plant's

        rate of transpiration?

  (b) Why might this calculated rate be slightly

         inaccurate (i) in daylight, (ii) in darkness?

  (c) What was the point of (i) watering the

        plant, (ii) enclosing the pot in a plastic bag?

	20

 

Photosynthesis and nutrition in plants

Photosynthesis and nutrition in plants

1 Select the most appropriate words from the list below to complete the...following

paragraph:

A green plant can make all the substances it needs. It builds up carbohydrates by the process of …….. In this process, it combines …….. from the …….. with ……. from the ……. to form …….  The …… needed for this process comes from ……., which is absorbed by the  ……. in the .……. of leaf cells. The waste product of the process is………

   soil, energy, oxygen, glucose, chloroplasts, mineral salts, cells, photosynthesis, air,  

  respiration, sunlight, water, nitrogen, chlorophyll, carbon dioxide.

2 Complete the following equation which summaries the process of photosynthesis

       …..CO…  +  6 ………                         C………… +  6 ….

3 What gases will be taken in and given out by a green plant (a) in darkness, (b) in bright

sunlight?

4 Is it possible for a plant to be photosynthesize and respiring at the same time?

5 (a) What carbohydrates does a plant make from glucose?

   (b) Which of these carbohydrates is transported round the plant?

   (c) Which carbohydrate is the main storage substance?

6 (a) What additional substances does a plant need to make amino acids and proteins from

        glucose?

   (b) Where do these substances come from?

7 What ions must a plant obtain from the soil in order to make (a) ATP, (b) chlorophyll?

8 Name an artificial fertiliser or fertilisers which farmers can use to increase the supply of

nitrate, phosphate and potassium to their crops.

9 (a) How would you destarch the leaves of a potted plant?

   (b) How would you check that the destarching had been effective?

l0 In a school laboratory, what is usually regarded as evidence that photosynthesis has

occurred in a plant? 

11 In designing an experiment to find out whether light is needed for photosynthesis

   (a) what is the principle of the design

   (b) what control would you use?

12 A leaf is detached from a tree and tested with iodine. The leaf turns dark blue.

   (a) What does this result tell you?

   (b) Why is this result not sufficient evidence to confirm that photosynthesis had taken place in     

         the leaf?

Cell division and chromosomes

Cell division and chromosomes

1 A cell in the basal layer of the skin contains 46 chromosomes and divides by mitosis to produce new skin cells. After ten successive divisions, how many chromosomes will the

basal cell have? 

2 The drawings below depict stages in the mitotic division of a cell

 

	A		B		C		D		E

 

   (a) Write the letters in the order in which these stages occur.

   (b) How many pairs of chromosomes are there in the cell?

   (c) What is the diploid number of chromosomes in these cells?

3 Choose the most appropriate word to complete the sentence.

   When chromosomes replicate, they produce ……...

        tissues, nuclei, chromatids, somatic cells

4 In which three of the following cells is mitosis unlikely to occur?

    a sperm cell, an epithelial cell of a villus, a hair cell, a cell in the red bone marrow, a red blood   

   cell, a lymphocyte, a cell in the basal layer of the skin

5 An animal has 36 chromosomes in each of its body cells. How many of these chromosomes came from its male parent?

B

A

6 Which pairs of chromosomes in the cell shown here

C

 are homologous?

	D

 

E

7 Fill in the missing words.

   The ….. A …..  of a cell contains a fixed number of

F

   chromosomes. Before mitosis, each chromosome

   ….. B ….. to produce two ….. C …...

8 The following drawings-show the sequence of events early in cell division.

   (a) Is the division meiotic or mitotic?

   (b) How do you know?

(iii)

(ii)

(i)

 

9 Give two examples in each case of organs or tissues in which you would expect

   (a) meiosis, (b) mitosis to be taking place.

Self-assessment questions                                                                                               21.02

Cell division and chromosomes (continued)

10 A fruit fly has four pairs of chromosomes in its cells. At meiosis, how many different

combinations of maternal and paternal chromosomes are possible in the gametes?

11 From the list below, choose the most suitable words to complete the sentence.

Mutations are changes which occur in a ….. A …..or a ….. B …... If a mutation

occurs in a cell which is going to form a ….. C ….., the mutation may affect the whole

….. D ….. which develops.

   Down's syndrome results from a ….. E ….. mutation In the ….. F…..

   Sickle cell anaemia results from a ….. G ….. mutation which affects ….. H ….. of the

blood system.

   cells, gene, gamete, chromosome, nucleus, ovum, organism

12 Exposure to ….. A ….., …..  B ….. or ….. C ….. may increase the rate of mutation

Suggest words or phrases for A - C

13 What kinds of mutation in disease-causing bacteria might make them more dangerous?

Plant structure and function

 

A

1 Name the parts of the plant shown in the drawing. 

2 Match the structures stem, leaf, root,

terminal bud, lateral bud to the following

B

functions:

   (a) produces carbohydrates

C

   (b) carries water to leaves

   (c) absorbs sunlight

   (d) continues growth in height

   (e) absorbs mineral salts

D

   (f) makes branches

   (g) anchors plant in soil

E

   (h) conducts food to roots

   (i) evaporates water 

   (j) produces new leaves

F

   (k) spaces out leaves

   (l) produces flowers

   (m) absorbs carbon dioxide

   (n) absorbs water.

3 The drawing represents a vertical section through a leaf x 200

   (a) Name the parts indicated by the letters

A

        A - E.

   (b) What differences can you see between

B

       the palisade cells and the spongy mesophyll cells

palisade cell

   (c) What is the function of C?

   (d) (i) Name the features represented in the

         diagram, which are thought to adapt the

spongy mesophyll cell

         leaf to its function in photosynthesis.

       (ii) Say how these features help to

        promote this process.

   (e) State three other structural features, not

C

         shown in the drawing, which are thought

D

         to be adaptations to the process of photo-

         synthesis in most leaves.

E

         Explain briefly how these features

         contribute to the efficiency of photosynthesis. 

4 Which of the following are most likely to be true? When the stomata are open, the leaf is

   (a) absorbing oxygen                        (d) giving off carbon dioxide

   (b) giving off water vapour               (e) giving off oxygen

   (c) absorbing carbon dioxide

5 (a) How many stomata are shown in this

        drawing of leaf epidermis?

0.1 mm

   (b) How many of the stomata are open?

   (c) How many are likely to be open at

        night?

   (d) What is the magnification of the

        drawing?

Self-assessment questions                                                                                                       6.02

Plant structure and function (continued)

6 (a) What process is responsible for the movement of carbon dioxide into a leaf?

   (b) In what conditions might the same process cause oxygen to enter a leaf?

7 The diagrams represent transverse sections through a root and a stem.

   (a) Say which one represents the stem and which one represents the root, giving your

         reasons.

   (b) Name the parts of these organs represented by the letters A-J.

	A

 

 

B

 

 

 

			Figure 1		Figure 2