9.Evolution

Question 1

what is a selective agent/pressure

Answer 1

a factor in an organisms environment that removes unsuited individuals from a population

Question 2

what is biological fitness

Answer 2

biological fitness is the ability to survive, reproduce and pass on alleles to the next generation

Question 3

VA scaffold

Answer 3

There is a variation in the phenotypes in the ________ population due to random mutations as __________

Question 4

ST scaffold

Answer 4

All organisms face a daily struggle to survive and reproduce, The ___________ with _________ struggle because __________ (selection pressures)

Question 5

SE scaffold

Answer 5

The ________ have a selective advantage as _______________________

Question 6

IN scaffold

Answer 6

The organisms that have a selective advantage (_____________), survive, reproduce and their offspring inherit the alleles for the trait of ______________

Question 7

E scaffold

Answer 7

Evolution occurs by natural selection and there is a change in allele frequency over time and the _________ population becomes better suited to its environment

Question 8

what order do humans belong to

Answer 8

primates

Question 9

identify shared characteristics of primates

Answer 9

1.Prehensile or grasping hand
2.Opposable thumbs(s)
3.Flat finger nails instead of claws and sensitive tips of digits
4.large, forward facing eyes
5.large brain volume in comparison to body size

Question 10

what is meat by bipedalism

Answer 10

walking on two legs rather than four

Question 11

advantages of bipedalism

Answer 11

-more energy efficient than walking on four legs
-bipeds can see further than quadrupeds of similar size
-able to hold objects while walking

Question 12

disadvantages of bipedalism

Answer 12

-slower top running speed
-greater visibility to predators
-greater pressure on spine and back muscles

Question 13

identify hominid characteristics

Answer 13

-reduced arm-to-leg ratio
-pelvis more bowl-like
-loss of opposable big toe/thumb
-larger heel bone (calcaneus)
-foramen magnum moved under base of skull
-increased brain to body ratio

Question 14

describe arm to leg ratio in hominids

Answer 14

-humans have shorter arms in comparison to leg length than the primates and hominids
-being no longer arboreal, long arms are not required
-shortening arms makes walking more stable and saves energy
-makes precision tasks easier

Question 15

describe pelvis in hominids

Answer 15

-human pelvis has evolved to become more bowl like than those of quadrupedal primates
-this spreads mass of the upper body which is now supported by two legs, resulting in reduced pressure on pelvis and increased stability

Question 16

describe opposable thumb/toe in hominids

Answer 16

-an opposable thumb on the foot is selected against if bipedal
-a big toe aligned with the rest of the foot enables toes to become flatter against ground, improving stability when walking

Question 17

describe heel bone in hominids

Answer 17

-calcaneus has enlarged to support the effect of increased body weight on the feet
-an arched foot is also a feature of more recent hominids as another pressure-reducing measure

Question 18

describe foramen magnum in hominids

Answer 18

-the is the hole base of the skull through which the spinal chord passes
-being bipedal, the head is better balanced if the foramen magnum is more central to the base of the skull

Question 19

describe brain size in hominids

Answer 19

-sperm whale has largest brain in animal kingdom
-hominids have relatively large brains for our body size
-

Question 20

what are genetically modified organisms +eg

Answer 20

these are organisms whose genome has been altered in some way
eg Flavr Savr tomatoes, where genes responsible for ripening have been removed

Question 21

what are transgenic organisms +eg

Answer 21

they are genetically modified organisms where genes from a different species are added to their genome
-known as a transgene

eg.Bt cotton (transgenic insecticide genes from bacteria added to cotton)

Question 22

Biological implications of genetically modified organisms

Answer 22

-GMOS may have effects on the environment, ecosystem and other living things
-GM crops may cross pollinate with a related, wild species

Question 23

T of F all TGOS are GMOS

Answer 23

true- all TGO’s are GMO’s

Question 24

Social implications of genetically modified organisms

Question 25

ethical implications of genetically modified organisms

Answer 25

-may be morally incorrect to genetically modify and organism
-questions on who owns a gene, or the genome of an altered crop