Download HighFour Biology Round 1 Category C: Grades 9 – 10 Friday

HighFour Biology
Category C: Grades 9 – 10
Round 1
Friday, September 18, 2015
The use of calculator is not required.
Answer #1:
Explanation:
Carrot / Carrot plant
The first trophic level is occupied by primary producers, which generate
their own food from the conversion of solar energy to chemical energy.
Most primary producers are plants, because of their inherent ability to
produce their own food.
Answer #2:
Explanation:
Mutualism
Symbiotic relationship refers to the interaction between species, which
may either be beneficial or harmful. A type of symbiotic relationship is
mutualism, where all participating organisms benefit from the situation. In
the situation that was described, the leaf-cutter ants and the fungus are
clearly in a mutualistic relationship, because both of them cannot live
without the other.
Answer #3:
Explanation:
Camouflage / Protective coloration
Camouflage or protective coloration is the general term for the structural
adaptation involving the blending in of the texture or color of an organism
to its environment as a way to improve survival and reproduction. A good
example of camouflage/protective coloration is the ghost mantis
(Phyllocrania paradoxa) with its leaf-like appearance.
Answer #4:
Explanation:
Carrying capacity
In the logistic model of population growth, carrying capacity refers to the
maximum number of population an environment can support. The
environment in this scenario refers to the 1-mL culture of nutrient broth.
On the other hand, the value “109 cells” represents the carrying capacity,
because it describes the maximum number of organisms the nutrient broth
can handle.
Answer#5:
Explanation:
Tundra
Tundra is a biome characterized by extremely cold climate and little
precipitation. As a result of the extremely cold temperature, some layers of
the ground become permanently frozen. This frozen layer is called the
permafrost, one of the landmark geographical features of tundra.
HighFour Biology
Category C: Grades 9 – 10
Round 1
Friday, September 18, 2015
The use of calculator is not required.
Answer #6:
Explanation:
Omnivore
The feeding pattern of a sheep is that of an herbivore, because it only
consumes plant materials. On the other hand, humans are a classic
example of omnivores, on account of their consumption of both plant
materials and animal meat.
Answer #7:
Explanation:
Rudolf Virchow / Virchow
The first two tenets of the cell theory, namely “All living things are made up
of cells” and “The cell is the basic unit of structure and function in
organisms”, were conceptualized by Matthias Schleiden and Theodor
Schwann in 1838. Rudolf Virchow then proposed a third tenet stating that
“All cells come from preexisting cells”, after having observed cell division.
Answer #8:
Explanation:
Oxygen
Bacteria have various respiration mechanism. Obligate aerobes are unable
to survive without oxygen. Facultative aerobes can survive with or without
oxygen. Clostridium tetani, the bacterium responsible for tetanus, is an
obligate anaerobe, making it incapable of surviving in the presence of
oxygen.
Answer#9:
Explanation:
Ichthyology
Ichthyology comes the words “ikhthus” (fish) and “logos” (study). It is the
subfield of biology dedicated to the study of all types fishes, including bony
fishes (Osteichthyes), cartilaginous fishes (Chondrichthyes), and jawless
fishes (Agnatha).
Answer#10:
Explanation:
400
The total magnification can be obtained by multiplying the eyepiece power
(10 X) with the objective power (40 X). Thus, the total magnification is 400
X (10 * 40).
HighFour Biology
Category C: Grades 9 – 10
Round 1
Friday, September 18, 2015
The use of calculator is not required.
Answer #11:
Explanation:
Phyllotaxy
Phyllotaxy is the pattern of the arrangement of leaves of plants along their
stems. The pattern of arrangement can give an insight into distribution of
the hormone auxin along the plant stem, as leaves only grow on areas
where auxin is depleted.
Answer #12:
Explanation:
Chloroplast
Chlorophyll is an extremely important pigment in plant photosynthesis
because it facilitates the absorption of light for conversion into chemical
energy. Chlorophyll is housed in the chloroplast, a plant-specific organelle.
Chloroplast gets its green color from the presence of chlorophyll.
Answer #13:
Explanation:
Conjugation
Genetic recombination allows the uptake of DNA molecules by most
bacteria. Although genetic recombination helps build detrimental traits like
antibiotic resistance through the uptake of genes that encodes damaging
molecules, it has also played an important role in the development of the
biotechnology industry and the cloning of several genes. One way to
accomplish recombination is through conjugation, wherein direct contact is
necessary for successful transfer of genetic material.
Answer #14:
Explanation:
Salt
Halophiles are salt-loving organisms that inhabit or dwell in saline
environment, such as the Great Salt Lake in Utah, USA. If halophiles are
present in an area, it could be concluded that the said area has a high
concentration of salt.
Answer #15:
Explanation:
Plasmodium
Malaria is caused by protozoan parasites that belong to the genus
Plasmodium. Four species of Plasmodium are implicated in malaria, namely
P. falciparum, P. vivax, P. ovale, and P. knowlesi. Transmission of malaria is
exclusively accomplished by Anopheles mosquitoes.
HighFour Biology
Category C: Grades 9 – 10
Round 1
Friday, September 18, 2015
The use of calculator is not required.
Answer #16:
Explanation:
Bacteriophage
Many do not consider viruses to be living organisms because of their
inability to replicate on their own. Viruses are largely dependent on their
host, as they take advantage of their host’s machinery to produce their
components. Some viruses only infect bacteria, and they are aptly called
bacteriophage.
Answer #17:
Explanation:
Population
A population is the smallest unit or level of organization that can evolve.
Evolution is the overall process of change in the genetic material over time.
An individual cannot evolve in its lifetime, but a population is subject to all
forces of variation, including natural selection.
Answer #18:
Explanation:
Cell wall
In contrast to animals, plants derive their structural rigidity from the extra
layer of cell wall found in their cells. This rigidity results from the presence
of either cellulose, hemicellulose, or pectin.
Answer #19:
Explanation:
Black Death
Population growth is limited by both density-dependent and densityindependent factors. The effect of density-independent factors is not
reliant on the size of the population. On the other hand, density-dependent
factors are chiefly affected by the size of the population; for example, a
disease spreads more easily in an overcrowded area with large population
growth. In this example, the Black Death plague is the density-dependent
limiting factor.
Answer #20:
Explanation:
Transpiration
Plants contribute to the water cycle through the process of transpiration. In
transpiration, water exits the parts of the plant to return to the
atmosphere. As a side consequence, this process enhances the nutrient
uptake of plants through increased gas exchange when plant pores are
open.