Micro Micro
On theme
Evo
Conservation
100
What is the benefit of using stains.
Staining is a crucial technique in microscopy that enhances the visibility and contrast of biological specimens, allowing for detailed observation of cellular structures and microorganisms.
100
How do analogous structure prove the diversity of life?
Even though organisms may have unity in the need to carry out the same functions, like in the case of animals with wings, the structure has different origins, which causes diversity in the structure. Such as bat wings and insect wings which.
100
A population of fish in a lake gradually splits into two groups that no longer interbreed. What must be true for this to be classified as a speciation event?
The two groups must be unable to produce fertile offspring
100
A region once containing a complex wetland ecosystem has been drained and urbanized. Which of the following consequences is least likely to occur?
A. An increase in ground water discharge
B. Reduction in native bird species
C. Loss of breeding sites for amphibians
A. An increase in ground water discharge
200
What is the function of structure II
The nucleus stores the DNA, which is condensed by histones, and is the site of transcription. It is also responsible for making ribosomes in the nucleolus.
200
How do homologous structures prove the unity of life?
Homologous structures despite having different functions, such as a human hand and a bats wing, since they share an origin in the same common ancestor, they are a form of unity.
200
Pentadactyl limbs are found in a range of vertebrates, including whales and bats. Which statement best explains the evolutionary significance of this?
They reflect descent from a common five-digit limb structure
200
What is a direct consequence of the conversion of Southeast Asia’s dipterocarp forests to monoculture plantations?
Loss of species, habitat loss, releasing of co2 into the atmosphere, decomposition of peat
300
Chloroplast and amyloplast are both examples of what organelle seen in this image
Plastids
300
What is a unifying characteristic of plants and animal cells
Nucleus, plasma membrane, cytoplasm, 80s ribosomes, membrane bound organelles (mitochondria, Golgi apparatus, endoplasmic reticulum)
300
The following list shows the base sequences of a gene from different species. Which species pair shows the greatest evolutionary divergence?
Species A: ATG GCA TCC TGA GCT
Species B: ATG GCC TCT TGA GCG
Species C: ATA TGA ACC TAA ACC
Species B and C
300
Which factor contributed to the extinction of the Caribbean monk seal and similar marine species?
Hunting for blubber and disruption of breeding ground
400
Why is the Scanning (lower) powered objective used when first focusing on a slide under the microscope
a. it is easier to find the specimen using a low power objective lens
OR
there is a larger field of view/depth of focus;
b. it is easier to locate the most interesting part of the specimen with a
low power objective lens;
c. most microscopes are calibrated so that once in focus using the low
power objective lens they will be close to focus using the higher power, so
this helps focusing;
d. reduced risk of cracking the slide;
400
What is speciation, and how does it represent the theme of unity and diversity?
Speciation is when a species diverges into two species, it shows unity from a shared ancestor, but diversity having differences accumulate to the point of no longer being able to produce fertile offspring.
400
Species arise and change over time through evolutionary processes.
State two sources of genetic variation.
Mutation, crossing over, independent assortment during meiosis, random fertilization, sexual reproduction, gene flow, chromosomal duplications or rearrangements.
400
Describe an anthropogenic cause of biodiversity loss happening in your country
can be related to urbanization, pollution,
hunting
and other forms of over-exploitation; urbanization; deforestation and clearance of land for agriculture with
consequent loss of natural habitat; pollution and spread of pests, diseases and invasive alien species due
to global transport.
500
Identify the mitochondria
small light circles
500
DNA sequencing reveals a 98.8% similarity in gene sequences between humans and chimpanzees. What does this high similarity provide evidence for?
Recent common ancestor
500
Explain how new species can arise through speciation.
a. population becomes reproductively isolated; 1 mark
b. no gene flow occurs between subgroups; 1 mark
c. different selection pressures in different environments; 1 mark
d. mutations accumulate independently; 1 mark
e. genetic drift affects isolated populations; 1 mark
f. behavioral, temporal, or geographic barriers emerge; 1 mark
g. eventually subgroups cannot interbreed; 1 mark
h. formation of a new species = speciation; 1 mark
i. example: finches on Galápagos islands, bonobos and chimpanzees
Explain how new species can arise through speciation.
500
Describe an approach to conservation
No single approach by itself is sufficient, and different species require different measures. Include in situ
conservation of species in natural habitats, management of nature reserves, rewilding and reclamation of
degraded ecosystems, ex situ conservation in zoos and botanic gardens and storage of germ plasm in
seed or tissue banks.