Pakistan International School, English Section,
Riyadh
Biology Worksheet: 1
Chapter: 15 Variation
Grade: 7
Name: _____________________
Section: _______________
Q1: Classify the following variations as either;
i)
ii)
Caused entirely by genetic effects.
Caused by a combination of genetic and environmental effects.
Obesity
Eye colour
Tallness
Gender
Blood group
Natural hair
colour
Caused entirely by genetic
effects
Caused by a combination of
genetic and environmental
effects
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Q2: Differentiate between genus and species?
Genus
Species
Q2: Following are the scientific names of some organisms, along with their common
names in brackets:
Canis familiaris (Dog)
Equus caballus (Pony)
Canis mesomelas (Jackal)
Equus burchelli (Zebra)
Commiphora angolensis (Sand Corkwood)
Commiphora africana (African Myrrh)
a) Write down the scientific name of two organisms which have same genus?
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b) Write down the common name of two organisms that have different genus?
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Q3: Look at the figures given below:
Identify the group for each organism to which it belongs and write down only one
characteristic of that group:
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Q4: Identify the scientific names of following organisms with the help of
dichotomous key:
i)
Dichotomous key I:
Dichotomous key to representative birds
1. a. The beak is relatively long and slender (very narrow)
Certhidea
b. The beak is relatively stout (thick & strong) and heavy
to 2
2.a. The bottom surface of the lower beak is flat and straight
Geospiza
b. The bottom surface of the lower beak is curved
3
..……
…….. Go
….…
……. Go to
3.a. The lower edge of the upper beak has a distinct (clear) bend ………
Camarhynchus
b. The lower edge of the upper beak is mostly flat
……..
Platyspiza
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ii)
Dichotomous Key II:
Dog
Skunk
Shark
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Dolphin
Rose
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Eagle
Canary
Mushroom
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Oyster
Mosquito
Cow
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Ivy
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Pine tree
Turkey
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1. animal
not an animal
go to 2
go to 11
2. has wings
go to 3
no wings
go to 6
3. has feathers
go to 4
no feathers
4. flies high
does not fly high
5. often yellow
not yellow
Ochloerotatus
taeniorhynchus
go to 5
Meleagris gallopavo
Serinus canaria
Haliaeetus leucocephalus
6. lives in water
go to 9
lives on land
go to 7
7. has fluffy fur
go to 8
no fluffy fur
8. common pet
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Bos taurus
Canis familiaris
Mephitis mephitis
not a common pet
9. has fins
go to 10
Haematopus ostralegus
no fins
10. razor sharp teeth
Carcharodon carcharias
Tursiops truncates
pegged, pointy teeth
11. green
go to 12
go to 13
not green
12. grows tall
Pinus ponderosa
Rhus toxicodendron
does not grow tall
13. can be poisonous
Boletus edulis
Rosa sylvestris
not poisonous
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Q5: Identify the common names of organisms by the help of dichotomous
key:
(A)
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(B)
_______________
(C)
____________
(D)_____________
(E)_______________
(F)__________
(G)_________________ (H) ________________
(I) _________
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(J)________________
(K)__________________
(L)________
Create a dichotomous key using the following list of specimens: pine
tree, clam, rock, robin, tin can, deer, oak tree, mouse, dandelion,
Paramecium, bicycle, ant
Here's an example in written form using these items:
1. a. Organism is living........................................................go to 4.
1. b. Organism is nonliving..................................................go to 2.
2. a. Object is metallic........................................................go to 3.
2. b. Object is nonmetallic..................................................ROCK.
3. a. Object has wheels......................................................BICYCLE.
3. b. Object does not have wheels......................................TIN CAN.
4. a. Organism is microscopic...................................PARAMECIUM.
4. b. Organism is macroscopic............................................go to 5.
5. a. Organism is a plant.....................................................go to 6.
5. b. Organism is an animal.................................................go to 8.
6. a. Plant has a woody stem..............................................go to 7.
6. b. Plant has a herbaceous stem.................................DANDELION.
7. a. Tree has needle like leaves.....................................PINE TREE.
7. b. Tree has broad leaves............................................OAK TREE.
8. a. Organism lives on land................................................go to 9.
8. b. Organism lives in water...............................................CLAM.
9. a. Organism has 4 legs or fewer......................................go to 10.
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9. b. Organism has more than 4 legs...................................ANT.
10 a. Organism has fur........................................................go to 11.
10 b. Organism has feathers................................................ROBIN.
11 a. Organism has hooves.................................................DEER.
11 b. Organism has no hooves............................................MOUSE.
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