1968-06-08 — Page 23

12.

青 製劑

A

8 JUN 1968

茛兰第六第

日三十月五年申戊震夏

WAH KIU YAT FOITE HALLE

英中會考生物科答案

(M)

•

廖百鑒·

Suggested answere

Hibisens

BIOLOGY

H.. Certificate of Education Examination 1968

Ans. (a) The sketches below are experimental

Fresh potato

apparatus to demonstrate osmosis in living aells.

•Sugar solution

Boaked potato

I water

A vertical Section f flower

The structures possessed by this flower in the adaptation of insect-pollination are:- (i) petals are brightly red coloured and

scented.

(11

The flower possesses nectary gland. (iii) The pollen grains are not very numerous

and are rele tively large. sticky and rough-coated.

(iv) The stigmas are smooth and with sticky

surface.

A

六鹅臺

日八月六年八六九一麼公牢七十五国茂生

Conjugation

tube

B3 The formation of

the gametes in

two adjacent cell,

At the beginning of the experiment

At the end

solution overflows

J

the

No change

experiment

Two skin-peeled potatoes A and B were taken in 4, concentrated sugar solution was introduced up to about half way of the scooped cavity. Potato was first cooked to kill the living tissues, then an equal amount of sugar solution wae added to cavity. These two potatoes were placed in a brough of water for a time,

the

By observation we noticed that the eugar solution in the potato A had over- flown after a time. This indicated that the tissues of the potato had been acting as a semi-permeable membrane which allowed water to diffuse into the sugar solution as a result of osmosis. No change was shown in potato B because the living cells of B were killed by pre-cooking and the tissues were no longer semi-permeable, thus the Пrocess of osmosie failed to take place

(b) The process of metabolism in every living"

cell of the body results 10 the pruduction of waste products euch as carbon dioxide, excess water, excess salts of calcium, bile-pigments, ures and ammonia, Therefore excretion in a living organies is the elimination of metabolic waste producte from the body. The excretion is necessary for the living organisms because most of the metabolic waste producte poisonous, if they accumulate in the body to a certain level, they will become toxi substances witch harm and even kill the organisms. On the other hand the accumule tion of the wastee will apset the metabolle process.

are very

Uuring the procese Of excretion- liver function81-

v The flower shape le specially adapted

for the visits of insecta which possess a long proboscis. e.z. the butterflies.

(b) Spirogyra reproduces by :-

(1) fragmentation: Under the favourable conditions, the plant may carry out vegetative propagation by means of the fragmentation. This is simply the breaking of the filament into short pienes containing one or more cells.

Each piece than grows in length by cell division and finally it obtains the normal length of the filament. (11) conjugation: In conjugation, the new

individual filament is developed from the zygospore formed by the fusion of two similar gametes. This process usually takes place in adverse conditiona

Scalarlorn conjuktion:

I

the scalariform Conjugation he sella two different Individ filamenta are converted.

A

short projection

gamete

Sugat Tube

I

C. The contents of one call flow into Hee adjacent call through the conjugation, tube

зудове

D. After the fusion of the contents of two formed. The New filament is also developed from the zygote.

cells, the zygote

is

14. The life-history of have bee (complete

metamorphosis):-

Egg Stagei

The egge are produced by the queen bee, and are laid one by one in the cells where they have been cared very carefully. As in hatching, those laid in worker cells develop into workeri in queen cells they develop into queens, while the unfertilized eggs laid in arone cells become the drones. All eggs are hatched within about three days.

RARIES

(1) to convert the excess amino-acids urea by means of deamination.

into

(ii) to excrete the break-down products of

haemoglobin in the form of bile pigments. (iii) to convert the toxic substances

harmless materiale.

lung functions-

in to

(i) to remove amount of exoess water in the

form of water vapour.

(ii) to expire carbon dioxide by the procAKO

of expiration.

kidney ruNO TJ DNB I-

(1) to excrete

tne Bi trogénone was Te

ае

ID

the form of urine.

(ii) to eliminate excess water.

(iii) to filter the soluble substances in

. blood hence retains the useful

substances.

13. Ans.

(a) e.g. Hibiscus

Stigmas

Anther

corolla -style

·Staminal Column

Ovary

Calyx

•Ovules

New

filament

projection appear on the side

opposite cells.

A short

wall

of

and

the

two

projections get

in contact

and walls of the projection

dissolue and a

one cell move

e tube

is formed between two cells the Contents f the tube to the opposite cell.

other filament

across

of

the

C. The zygote is formed from the contents

оз

two cells

J

the two filaments.

D. Under favourable condition, the

into a zygote grows

new filament

cell division

Lateral conjugation

LWO

In this case the conjugation concerns odjacent gella of one individual filament.

1 gametes

1. A living filament. I

Larval Stage:

The larva of different type of bee is usually legless. The larva in its own cell to fed by the worker with the appropriate food.

larval, ataga normally lasts for one week, Ping which the larva moults six timse and then bates.

stage

After about six times of moulting the larva is ready to pupate. Its cell is then capped with wax by the workers. The pupal stage ban lasts for 4 to 5 days, then the capping is broken down and the imago.emerges.

Egg

Mature young larva larva

Adult Stage 1-

+

-capped"

call

Дрира

three types, the worker

The adult bees are classified to namely the queen (fertile female), (sterile female), and the drone (eterile male). They are all winged, and capable of flight. but different in size,

The hive bees live in organized communites and inhabit in a hive. The colony duties must be performed by the different individuale such as the queen. the worker and the drone.

eeri

It le developed from the fertilized egg in the queen cell. When the egg is hatched forming female larva which is fed by royal juice. In the colony of the hive-bee, the queen La mother of the other bees, if the queen dies without a new queen to take over her position. the colony soon dies. The main work of the queen is for producing ezas.

Urone 1-

It is formed from the unfertilized egg. When hatching its larva is fed by pollen grain or nectar. During the mating time, it mates with the queen, after this it lives for a few weeks -and-19-killed by the worker. The drone may also

help the workers in the storing of pollen and nectar in the 'combe.

worker:

The worker 18 developed from the fertilized egg. It is a builder of honey-comb. In addition it received nectar and pollen grain brought to the hive or carries debris and dead been out of the hive, taking them off some distance and dropping them. A certain number of wax-secreting beee guard the entrance of the nest. inspecting All incomers to be eure that they are bees of their colony.

......