Page 231 - SCIENCE DLP T6 SK (SEMAKAN 2017)

SUGGESTED ANSWERS AND REFERENCES (ii) the sense of hearing sends a signal to the brain
through the peripheral nerves
SUGGESTED ANSWERS (iii) the brain sends signal to the hand
(iv) the hand picks up the phone
UNIT 1 SCIENTIFIC SKILLS
Mind Test (pages 11-12) stimulus sense organ brain hand response
1. Manipulated variable: methods of harvesting paddy UNIT 3 MICROORGANISMS
plants Mind Test (page 50)
Responding variable: land area
Constant variable: type of plant 1. (a) virus (b) algae
2. (a) Observation: Mango B is heavier than mango A. (c) protozoa (d) fungi
Inference: Mango tree B obtained sufficient basic (e) bacteria
needs such as water, air, sunlight, and nutrients. 2. (a) Paramecium
(b) Mango B is bigger in size compared to mango A. 3. (b) The position of the Paramecium changes.
3. The higher the concentration of the liquid, the longer 4. (c) Because the Paramecium moves
the time taken for the liquid to flow out. 3. (a) Dough C is the largest in size.
4. (a) the animal’s method of reproduction or other (b) Dough C is the largest in size because the most
suitable characteristics amount of yeast was added to dough C or because
(b) eating habit or other suitable characteristics the largest amount of gas was released by the
(c) accept pupils’ classification charts yeast in dough C.
(accept any suitable characteristics) (c) breath
(d) The size of the dough increases because the dough
UNIT 2 HUMANS itself provides nutrients for the yeast to become
Mind Test (page 31-32) active and able to breathe.
1. (a) Organ: testis 3. 4. Accept any suitable answers.
Function: a place where sperms are produced.
(b) Organ: penis UNIT 4 INTERACTION AMONG LIVING
Function: transfers sperm into the female THINGS
reproductive organ Mind Test (page 66)
2. (a) The zygote divides itself to form multiple cells known 1. (a) relationship (b) depend
as the embryo. (c)
(b) A place where embryo develops to form foetus 2. Type of Interaction (d) Situation
(c) No, ovum is not produced.
Compete for limited number of mates.
Prey-predator (e)
3. (a) (i) sperms (b) (i) swim (f)
(ii) vagina (ii) ovum Intraspecies competition Cheetahs hunt gazelles
(iii) fuse Competition between vultures
Interspecies competition
(c) (i) ovum (d) (i) embryo and lions
(ii) zygote (ii) foetus Symbiosis Remoras get free transport
from sharks
(e) (i) foetus (f) (i) foetus 3. (c) crabs - barnacles
(ii) nine (ii) baby
4. Type of Symbiosis
4. (a) central nervous system
(b) peripheral nervous system Mutualism Parasitism Commensalism
5. (a) Zaimi pulled his hand away when he touched a Benefits both Benefits one Benefits one
hot kettle. This requires an immediate unconscious organisms organism but organism but does
harms the other
not benefit nor harm
response or reflex action. In this situation, the spinal the other
cord receives the signal and produces a response Example: Example: Example:
from the body. The signal pathway is as follows. crocodile and bird cat and tick remora and shark
(i) the skin receives the stimulus through the sense
of touch
(ii) the sense of touch sends a signal to the spinal
cord through the peripheral nerve 5. The types of interactions among plants are:
(iii) the spinal cord sends a signal to the hand (a) Competition to obtain water, sunlight, space,
(iv) the hand is instantly pulled away and nutrients.
(b) There are two types of symbiosis. They are
stimulus sense organ spinal cord response
commensalism and parasitism.
(b) Siti heard her phone ring. This response is a (i) Commensalism
voluntary action which involves the central nervous Bird’s-nest ferns grow on large trees. They
system controlled by the brain and peripheral
nervous system. The signal pathway is as follows: depend on the host plants to obtain support and
(i) the ears receive the stimulus through the sense sunlight but do not harm them.
of hearing Orchids grow on the trunk of the host plant
for support, sunlight, and nutrients from their
surrounding. At the same time, the host plant is
not harmed nor does it gain any benefits.

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