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Biology
A. Primary consumer
B. Secondary consumer
C. Tertiary consumer
D. Decomposer
Answer: Primary consumers (herbivores) feed directly on producers (plants).
Biology
A. Grass
B. Lion
C. Mushroom
D. Eagle
Answer: Mushrooms are fungi that break down dead organic matter, recycling nutrients back into the ecosystem.
Biology
A. Bacteria
B. Temperature
C. Trees
D. Insects
Answer: Temperature is a non-living (abiotic) component of an ecosystem.
Biology
A. Lipids
B. Carbohydrates
C. Proteins
D. Nucleic acids
Answer: Enzymes are proteins that speed up biochemical reactions without being consumed.
Biology
A. Cell -> Organ -> Tissue -> Organ system
B. Cell -> Tissue -> Organ -> Organ system
C. Tissue -> Cell -> Organ -> Organ system
D. Organ -> Tissue -> Cell -> Organ system
Answer: Biological organization progresses from cells to tissues to organs to organ systems.
Biology
A. Living organisms
B. Preserved remains of ancient organisms
C. Genetic mutations
D. Embryonic structures
Answer: Fossils are preserved remains or traces of organisms from past geological ages.
Biology
A. 6.4
B. 7.0
C. 7.4
D. 8.0
Answer: Human blood pH is tightly regulated between 7.35 and 7.45 by buffer systems.
Biology
A. Oxygen
B. Nitrogen
C. Carbon dioxide
D. Hydrogen
Answer: CO2 traps heat in the atmosphere, preventing infrared radiation from escaping to space.
Biology
A. Adenosine triphosphate
B. Adenosine diphosphate
C. Adenine triphosphate
D. Amino triphosphate
Answer: ATP (Adenosine triphosphate) is the primary energy currency of the cell.
Biology
A. Sucrose
B. Maltose
C. Fructose
D. Lactose
Answer: Fructose is a monosaccharide, a simple sugar that cannot be hydrolyzed further.
Biology
A. Plantae
B. Animalia
C. Fungi
D. Protista
Answer: Fungi are heterotrophic organisms that absorb nutrients, including mushrooms, yeasts, and molds.
Biology
A. Non-competitive inhibition
B. Competitive inhibition
C. Irreversible inhibition
D. Allosteric inhibition
Answer: Competitive inhibitors compete with the substrate for binding at the enzyme\'s active site.
Biology
A. Tundra
B. Desert
C. Tropical rainforest
D. Grassland
Answer: Tropical rainforests have the highest species diversity due to warm temperatures and abundant rainfall.
Biology
A. Glycosidic bond
B. Peptide bond
C. Phosphodiester bond
D. Hydrogen bond
Answer: Peptide bonds form between the amino group of one amino acid and the carboxyl group of another.
Biology
A. They are consumed in reactions
B. They increase activation energy
C. They are specific to substrates
D. They work at all temperatures
Answer: Enzymes are substrate-specific due to the complementary shape of their active site.
Biology
A. Competition
B. Predation
C. Natural disaster
D. Disease
Answer: Natural disasters affect populations regardless of their density.
Biology
A. Food web
B. Energy pyramid
C. Biogeochemical cycle
D. Ecological succession
Answer: Energy pyramids show the decrease in available energy at each trophic level.
Biology
A. Organic solvents
B. Chloroform
C. Water
D. Benzene
Answer: Lipids are hydrophobic molecules that are insoluble in water but soluble in organic solvents.
Biology
A. Mitochondria
B. Nucleus
C. Cytoplasm
D. Endoplasmic reticulum
Answer: Glycolysis takes place in the cytoplasm, breaking glucose into two molecules of pyruvate.
Biology
A. Number of genes in a species
B. Variety of life in a given area
C. Number of cells in an organism
D. Rate of evolution
Answer: Biodiversity is the variety of all living organisms including species, genetic, and ecosystem diversity.
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