Exam 4 Flashcards
True or False: Lactose intolerance is a condition that occurs if the body doesn’t produce enough lactase to break down lactose in the stomach.
False (Not the stomach; the intestines)
Based on what we’ve covered in lecture, which type of macromolecule would you expect ATP Synthase to be primarily composed of?
Proteins (Enzymes are proteins)
Koalas feed feces to their young to transmit bacteria that aid in digestion. Which type of macromolecule in particular are the bacteria helping to digest?
Carbohydrates
Pancreatic Lipase is an important enzyme in digestion. Which organelle is the primary site for synthesis of the same class of macromolecules that Pancreatic Lipase breaks down?
Smooth ER
Which of the following is both a requirement (input) and a product (output) of the aerobic cellular respiration process?
NADH
Why isn’t bile needed for the digestion of carbohydrates?
Carbohydrates are hydrophillic
Where would you expect to find sex chromosomes?
Both somatic cells and gametes
Where would you expect to find autosomal chromosomes?
Both somatic cells and gametes
How many times does DNA replicate in completing the full process of meiotic cell division?
1
How many times does DNA replicate in completing the full process of mitotic cell division?
1
In which of the following are the two genes (shown by black bars) most likely to be linked?
A (Chromosomes with genes on ONE chromatid and near each other)
Which of the following is most likely to represent a synonymous mutation to the following DNA sequence: AGG
D. AGA
True or false: If the two most closely related species on a phylogeny tend to co-occur, and occupy the same habitat, then speciation between them wasn’t allopatric.
False
True or false: Evolution is a process in which individuals evolve to gain higher fitness
False; population level, not individual
In which of the following interactions is coevolution least likely to occur?
Plant-pollinator because it’s mutually beneficial
True or false: Photosynthesis is a process in which plants create energy
False; uses energy to create glucose
Which of the following is both an input and a product during the photosynthetic process?
NADPH
Although individual trees can’t move, tree populations can migrate, if their seeds are dispersed to a new area. Based on the US Forest Service’s research in 1999-2008, are tree species in the eastern U.S. migrating in sync with climate change?
No
Biome:
A broad ecological community defined by vegetation type
Ex) Deserts, rainforests, grasslands
Biomes are determined by:
Climate: Temperature and precipitation
Duluth is:
“Boreal” aka “Coniferous” forest
Minnesota has four biomes:
Clockwise: Coniferous forest, deciduous forest, prairie grassland, tall grass aspen parkland
Coniferous forest
Ex) Balsam fir, pine trees, cones
Moose found here (like BWCA)
Deciduous forest
Ex) Maple trees, maple syrup, oak trees, leaves
Prairie
Compass plant, badger,
Tall grass aspen parkland
Basically a savannah
Deciduous tress in the fields
Ex) Aspen with sandhill crane
Prairies require fire:
Trees dominate without it
Prescribed fires
Controlled, low temperature fire
Without fire:
Grassland/savannah–>dry forest=huge, devestating fire
The scientific concept of biomes came from:
Alexander von Humboldt
Humboldt’s influence:
11 species, an ocean current, 4 universities, Humboldt, MN
Food webs:
Flow of energy within a biome
Illustrate complexity of energy flow
Energy flow through trophic levels
0.1% Apex predator
1% Consumers
10% Producers
100% Sun
The other 90%?
Lost as heat and incomplete digestion
Biomagnification:
Increase of toxin concentration up the trophic levels
How?
Producers absorb toxins, eaten by consumers and apex predators eat consumers
Biologists studied DDT (1944) warned it was highly toxic
Approved for use as a pesticide anyway (1945)
Banned in the USA (1972)
Ex) Thin eggshells
High biomagnification in the arctic
Pollutants collect in the arctic from distance sources
Intuit PCB concentration in 33 times higher than people in Southern Quebec
Biomagnification in Lake Superior
10% of newborn babies in Lake Superior basin have higher mercury levels higher than EPA standards
Population biology:
Growth, decline, interactions, and other aspects of populations
Survivorship curves reveal life history strategies
Most offspring die young=R strategists (small bodies)
Most offspring die old=K strategists (big bodies)
Ultimate R strategists: Mayflies
Lay up to 10,000 eggs
Adults live one day, mate, and die
Some adults have vestigial mouth parts
Population growth curve
Exponential growth phase
Equilibrium phase
Carrying capacity
The maximum population that an environment can support for a particular species
Boom and bust cycle around carrying capacity
Both R and K strategists boom and bust;
but oscillations are bigger in R strategist
R strategists reaches carrying capacity
sooner
Carrying capacity is labeled
K
K strategists
stay close to K
R strategists
oscillate farther from K (due to high productive rate)
Density dependent factors:
factors that limit population growth and become stronger in proportion to density
Predation risk
Limited food
Disease spread
Isle Royale is famous in population biology:
Only one wolf left Population can't grow Reach Isle Royale through ice bridge 1600 moose Released from density dependent factor of predation
Deer prefer
Maple
Canada Yew is highly preferred by deer but uncommon
Deer are responsible for
40% of the change
Density dependent factor for humans
Food
Population expected to reach
9 billion by 2050 (7.4 billion today)
To feed the growing population, food production must increase by
70% over the next 30 years
Several of the earliest domesticated species are still important today
Wheat, lentils, cattle
Multiple origins of some domesticated crops
Barley in the Middle east and Tibet
Most crops are
Annual plants (Annual=one growing season) Ex) Corn
Fewer crops are
Perennial plants (Many years, about one crop per year) Ex) Raspberries
Annuals:
Mature quickly, plant every year
Perennials
Mature slowly, plant once and maintain
Monoculture
Only one species planted
Highly efficient
Polyculture
Several species planted together
Minimizes pest risk
Agroforestry
Polyculture that incorporates trees
As many as 25 crop species in one plot
Problems in agriculture
Water loss-needed to irrigate, being used faster than it’s being replaced
Problems in agriculture
Soil loss-intense agriculture erodes soil, high winds blow topsoil away
Ex) Dustbowl of the 1930s
Problems in agriculture
Loss of biodiversity-Pesticides, habitat destruction, relies on pollinators (bees), corn is wind pollinated, and doesn’t offer nectar, flowering only lasts 2-3 weeks in almond trees
Many bees are active
for several months
Pollinators shipped in because
there aren’t enough bees
Apples and pears are
hand pollinated by people in Sichuan, China
Honeybees
Aren’t native to the Americas
20,000 bee species
in the world
~400 bee species
in Minnesota
Deseritfication
More dry, arid land
The process of desertification of the land,
usually driven by human activity
Deforestation
Exposed soil dries out quickly
Dry soil doesn’t absorb rain water and erodes
Trees struggle to grow in eroded areas
Reforestation prevents this
Overgrazing of cattle
Cattle eat vegetation, leaving bare land and compacted soil
Dams
Power about 1.3 million people
Flood water contains nutrient rich sediment
Goes into flood plain
Floodplain agriculture is important in human history
Omo River in Ethiopia
Dams
Disrupt floodplain ecosystems
Upstream reservoir
Floodplain permanently underwater
No agriculture possible
Sediment collects, bad for fish
Also clogs dam
Downstream reservoir
Not as much nutrient rich sediment
No sediment is bad for fish
Dams disrupt aquatic migration
Fish wants to go upstream to reproduce but can’t
Coaster book trout reproduction threatened
Fish ladders
Structures built into dams that allow fish to migrate upstream
Dam affect indigenous ways of life
Klamath people
Dams flood sacred sites, force people to move
Waboose dam-cemeteries now underwater
Dams destroy beautiful natural features
Sete quedas (waterfall)
Dams linked to earthquakes
Pressure added to fault lines; at least 100 earthquakes associated with dams
Early Roman dams:
Used for water storage
Hohokam people (1-1450 AD in Southern Arizona)
Built intensive canal systems for irrigation (agriculture including corn, beans, cotton)
80 million gallons of water used daily
At golf course in Maricopa, Arizona
Beaver dams
Deep water upstream of dam provides protection from predators
Same as regular dams transforming habitat
Although not as extreme
However,
Beaver dams don’t inhibit fish like human dams
Eucalyptus trees promote fire
Contain highly flammable oil=fire (like paper birch bark)
Trees survive fire, but resprout
Seeds released after fires and are invasive species in many parts of the world because they survive fires so well
Threats to species
- Habitat destruction
- Habitat fragmentation
- Invasive species
Habitat destruction:
Logging, mines, residential, farms
How much tall grass prairie remains in the US?
About 1%
Mead’s Milkweed
Occurs in prairies; federally endangered, smells like cloves
Who has the highest rate of deforestation in the world?
Indonesia
Because of this:
Orangutans are endangered; only found on two islands in Indonesia
Rainforests converted to Palm Oil plantations (not very diverse, like corn in US)
Orangutans:
“People of the forest”
orang=person
hutan=forest
Habitat fragmentation:
Areas of habitat
Are not equal to a continuous habitat of the same total area
Smaller population sizes, less genetic diversity
Small populations are vulnerable to extinction
Might not enter exponential growth phase
Inbreeding, low genetic diversity
Random events, reducing numbers
Many species require a minimum area to survive
Large species need large habitats (Bison have the Konza prairie in Kansas)
Invasive species
Kudzu: plant from Asia
Invasion and extinction through hybridization
Favored over both parent plants
Old growth forests
Often carry the same species as younger forests but are structurally different (higher DBH, more decomposing logs; providing homes for organisms)
Most of our deciduous trees were logged 100 years ago
Except the “Lost 40” in Itasca County
Conservation of processes:
Migration
River flooding
Biomes
Cross state and national borders
Sonoran desert
Animals want to cross (national) borders but can’t
Breeding endangered species in captivity and reintroducing them to the wild
Whooping Cranes imprint on what they first see when they hatch
Biologists wear whooping crane costumes so they don’t imprint on humans
Young whooping cranes follow “mom” for migration
Raptor education group in Antigo, Wisconsin
