-期星 日三十月一十年二七九一届公年一十六國民華中
有敢倍 頁第張六第日八初月十年子壬腊罗 WAH KIU YAT PO
郭日情
育僑榮
REFERENCE LIBRARY
/13 NOV.1972
CITY HALL
1978
中文中學會考試題預習專欄]
生物科 (三)
梁景植
1913英文中學會考試題預習專欄
經濟及公共事務科
Econonia & Public Affa exeroice.No.3
Questi on:(1) Whas as meant. dy elastic demand? Deoribe. the (Taotors that affect changes
demand .
¡ANSWERI
-ly does. The reverse is true when he earns less. For instance, aconsumer will buy more butter; when he earms more, and more marTM garine when he earms Less.
Changes in taxation. can also influence changes. in demand. For example, a higher tax on cigaret- tes may cause a drop in the demang for cigarettes, for it may deter people. from smoking or compel 3mokers to cut down their consumpi
Any drop in the use or some commodities, and any increase in others is certain to produce
changes in demand. The introduct-) ion of new commodities can also affect demand, Areated drinks for. instance have displaced beverages to a large extent especially in summer, After the war women have been known to spend more on cosmetics than on, other things.w
本期温晋内容
生活於水塘中的一些微小生物之形麵 生理及繁殖,本期首先温習要形虫,单 痘品其餘水絆,水螅下期绩 練習題:
下圖為变形蟲之形熊图
小安云图中各部
名称:
模式之動物与植物细胞比車 動物细胞 植物细胞 ,不具纖维素之细胞壁1.除生殖细胞外,均具 只有素之细胞膜| 有纖維素之细胞壁 乙除低等動物外細之除分生细胞外細胞 胞均不真液胞均具有明顯大液胞 3.細胞核侄在细胞3、细胞核常受液胞
台荷压而偏於一
14. 除眼蟲等低等動94细胞常具有黄绿素
4. 细胞均不含任 上細胞形態變化較5.因具空厚细胞壁之 故细胞形熊板固定。
DEMANDED
that Demand is elastre)
When a change in price, how ever small, it is, produces a great.. changes in the demand of the com modity; we say that the demand for that commodity is elastic"
Referring to the above dia- Bram, Hou will notice that DD is the demand curve, while the hori zontal axis (OY) represents the amount of the commodity that is demanded, and the vertical axis (OX) represents the price. You: will see that when the price drops from P. to F the quantity demand-
ed is increased from 0 to Q, but when the price drops from P2 to P
(which da an equal change in price the quantity that is demanded is increased from Q2 to Q3. which clearly shows a greater change in quantity: then when the price changes from P to F2. Thus, that) part of the demand curve (E E-) which shows a greater response to 1 similar change in price is known Is elastic demand,
Changes in omniu can tak place under different circumstances and caused by different factors.
Old commodities, fur instance, may.experience a drop in demand when they are replaced by new com- modities which are, on the other hand, demanded on a greater scale. For example, last summer the de- mand for mini-skirts in Hong Kong Buddenly rose, while that for maxi:: -skirts dropped.
unanges in demand can also be Jaused by a change in population. It is evident that an increase in the number of people in the countr wi11 eventually cause a greater.de -mand for goods and services, and vice versa when there is a drop in the population, Hong Kong, for in- stance, between 1931 and 1961, experienced an increase of 2.2 hillion people, and this eloquenti ly explains the steady increase in the demand of consumer goods. after the Firat World Warr
'Any change it. a persona in- come is also bound to effect the demand for goods and services. When a person earns more,: he tenda: to spend more on superior goods than on inferior goods, or he may purchase more goods than the normal
The above factors can influ ence changes in demand irrespect- ive of any changes in price. How ever, a a change in price itself, can also produce changes in de- mand. For instance, if the price of one commodity is raised, con- sumers may buy another commodity instead, " unless the former does not have a close substitute. If tea for instance, becomes more. expensive most people would pro- pably turn to coffee.
Question (2)- What-do you underw Btand by interrelated demand? Inta how many kinds can interrei– cated
demand fall? Give examples.
Answer:
When the demand for two dis- similar commodities is linked to- get:fur, so tiut an increase in thomand for one will cause a similar increase or drop in the other commodity, it is known as interrelated demand.
interrelated & sanil can fal into four different kindo: compaf- itive; demand; derived demandyjoint Lemand and composite demand.
Demand is said. to be compet- itive df the demand for one com- modity drops in response to a rise in the demand for another commodity Competitive demand occurs when apt -icles are close substitutes far each other, Take butter, and mars garine for instance, Arise in the Hemand for one will cause a drop
m the demand for another.:
veraved cemand occurs when a hange in the demand for one com- modity produces a change in the Jemand for another. Record-players and:gramophone .records are examples: or articles that have derived de- hand because, if the price of re- cora-players rises, there will be
drop in the demand for gramophone recoris,
By Jum ueriand 18 meant that change in the demand for one com modity will also produce a simil- un change in the demand for another. commodity. The demand for motor- bars would mean move petrol, and feman motoruna the Tess petrof)
men a commodity can be used for more than one purpose, the ic" äemand for it is said. to be comw posite, since if there is a rise in the demand for it fer one purs nosey the supply of the commodity: for other purposes:ill fall, For instance, timber can be used for.. making paper or producing furnit- ure. If more timber is used for :making paper there will be a drop in the supply of timber for pro- ducing furniture, so that the price of furniture will rise limoer is therefore said to have a composite demand.
ercise lio.4
(1) Describe briefly. the develop- nent of our monetary system, and point out the pros and cons of our
resent form of money.
2) How important is the Governor o Hong Kong)
·下列部分有何功能.
f
3.差沒着SS線將变形蟲功闸,分别堆 养於理想環境中经一週後,结果如何
試依上述结果作-结淪
4.試述变形向的赞弄法
試比較流運動与变形運動。
(二)下图為草履蟲的形態图.
(害云图中各部名称,
y2.持下列部分填入图中
適当位置 在伸縮胞以輻射管 j食物胞龙刺絲胞
3.你能在甚麼地方找尋到這西種微生物
4這些微生物如变形虫草履蟲等均缺少! 呼吸器及排泄器則這些微生物怎樣 行呼吸与排泄。
只何謂嘗試成功,試以單履在的行動
以说明之?!
6試害击上图
的功能
(三)試附图主说明草履蟲的楼合生
殖過程?
上期答案!!
Ja細胞壁,♭液胞,细胞核
d質體細胞質 f細胞間質 細胞有主宰细胞-切生理機如支 配细胞之代謝,特化,生長,分裂感皮革 由於细胞生長太迷,細胞不及補-
,於是吸 入水份以模先,但為着要维持细胞質修 透濃度稳定,故特价吸入之水份集中而形 而此液胞,因此液胞有维持细胞質之 湊屋5膨張作用
4.將細胞置於濃糖液中,由於外液之渗 透濃度大於细胞内细胞液之濃度,於 是水液便渗云细胞,结果和胞質萎缩 質膜便与细胞壁分離,故可在顯微 镜下观察到此薄膜。
(三)細胞学说是於1838年,由德周植物學家
Schleiden - ED 45 1 & Schwann my sle 由於近年科學之進步,陸續有所費現故修正 如下三奌要義:
山一均動物,植物及微生物都是由细胞
●及细胞之產物所構成,故细胞為一切生 物體構造上的最小單位。
(2)一切细胞的化学组成和生理代谢活動 基本上相同,生物整停之活動為獨立细胞 单位的活動和相互作用之綜合表現,故 细胞為生物生理活動上之最小單位、
(3)新生的细胞必由前存的细胞分裂而產生 故细胞亦為生物生殖與遺傳上之最下單位 四咇a中心體星絲c纺娃絲d染色體 分裂問期——A图;前期—BCD图 中期一E图;後期→下图;末期-G.H园 3.前期核中之变化:染色質聚集形成染色 絲 漸漸增粗成婆紐核仁及抟膜澌 漸消失,染色紐終於变成定数之染色俸, 中期核中三变化:染色倬排列於赤道和 因上而且於複制完成後縱裂為二。
上图為動物细胞之有絲分裂,因為從 お園可到下列西項現象
a在分裂遇程中有中心体及星际云现 6末期時胞膜心中收縊,分裂為二
ż》绒数分裂為有絲分裂中的一種特殊形式片 見於生殖细胞成熟時的分裂,故又称為成熟 分裂,其過程工一般有然分裂大致相同,亦分 為前期中期後期品末期,只是在中期時並未完 咸複制縱裂,而同源染色倬两两相配联會 其後分為西组各向-極移動,因此所生成之 子细胞所含有之染色体数,為母细胞染色 俓数之半,換言之由双套染色侍(22)分裂为 單套染色侍(九)的细胞有丝分裂,精母细胞 (或卵母细胞)经减数分裂後,便形成成盛之
精子(或卵子)
减数分裂之主要意義在於攸染 数得以 黑原因而推持生物倬染色诗数之稳定。
A. 巽化作用又称分解作用是指伴質分
解而釋放云能,以维持生命活動之進 行, 故侍質固不断分解而相耗.
同化作用又称组成作用,是將攝自外 界的榮养,藉一系列安之活動而组 成与本身一致的新特質,故同化的结 果使许質增加
B.排童:將消化不完全,或不被消化吸 收的食物殘渣排出细胞外或生物 体外的生理现称店排造 俳泄:將原生質经異化作用後所生 或之代谢废物,排示细胞外式生物 ̇424理现象称為排泄
要形運動由於細胞質之流動使 细胞外形主随之而改變達成移動 位置的目的,这種運動現象称為 变形運動
川流運動:细胞之外形不变细胞 質依盾-定方向循環流動,称為 川流運動