BIOLOGY TEST PAPER QUESTIONS
ANSWERS GRADED A+
◉ *Conservation biology:
Answer: study of biodiversity with the aim of protecting species and
ecosystems
-Societal angle -> conservation organizations generally appeal to human
sensibilities and aesthetics
◉ Biodiversity
Answer: : measure of biological complexity using species richness and
evenness in a particular area
- species richness: # of species living in a habitat
- species abundance: # of individuals of a species living in a habitat
◉ Types of Biodiversity
Answer:
◉ 1. Genetic diversity
Answer: : allelic and mutation variation
-Raw material for evolution and adaptation
,-Higher genetic diversity -> enhanced ability to endure selective
pressures
◉ 2. Chemical diversity
Answer: : variation in cellular products (proteins, metabolism
byproducts)
◉ 3. Ecosystem diversity
Answer: : variation of different ecosystems on earth/geographic region
-Survival of foundation species
-Adaptations for particular ecosystem
-Frequency of species interactions
◉ Why do conservation organizations tend to use mammals and birds to
promote their efforts?
Answer: Societal angle ( humans tend to care more about cute fuzzy
animals)
◉ Uneven species richness across the world
Answer:
◉ *Heterogeneity
Answer: # of ecological niches
,Low near the poles
higher near the equator
◉ Endemism
Answer: : condition of organisms/species distribution to a small defined
geographic location
◉ *Endemic species
Answer: : species found/native to a small defined geographic location
Low near the poles
High near the equator
◉ Cause of biodiversity
Answer: Main cause: : equilibrium between speciation and extinction
◉ 1) When speciation exceeds extinction
- increases in species richness
Answer:
◉ 2) When extinction exceeds speciation
, - reductions in species richness
Answer:
◉ Why is heterogeneity so important for species richness?
Answer: The number of available niches directly impacts how many
species can live in an ecosystem
◉ Mass extinctions
Answer: : periods/incidences of excessive extinction relative to
speciation
◉ 1: Ordovician extinction
Answer: -85% marine species
-First mass extinction event
Cause(s):
-Climate change
-Temperature fluctuations
-Sea levels
◉ 2: Devonian extinction
Answer: -70-80% marine species