Exam 2 pt. 2 Flashcards
List all Biomes
Boreal Forest Desert Mediterranean and Chaparral Tropical Rain Forest Tundra Temperate Grassland Temperate Forest Savanna
Tropical Rain Forest
abundance of resources
biodiversity “hotspots”
high species richness
Tundra
permafrost: soil is frozen throughout the year and is rich i organic matter
low plant diversity
Temperate Grassland
very productive
domesticated, anthropogenically transformed
Boreal Forest
coniferous or taiga, largest terrestrial biome
low diversity of tree flora: pines, firs, spruces
pest outbreaks
Savanna
tropical grassland w/scattered trees
tree growth checked by limited seasonal moisture, grazing, and fire
Desert
little, unpredictable rainfall
low productivity
low species diversity
plant adaptations
Temperate Forest
moderate temperature and precipitation
Deciduous and evergreen trees
rich in organic matter
Mediterranean and Chaparral
mild/wet winters
hot/dry summers
frequent wildfires
Climate
weather over a long period of time
Biome
a major category of the world’s distinctive plant assemblages
Continents
Pangaea
Laurasia
Gondwana
Rain shadow
region with little rainfall because it’s sheltered by hills
El Nino
Between 3-7 yrs, warm water moves East along the equator and rests in the Pacific, near S. America
The warm water evaporates and moves north, providing extra rainfall across the South US for a couple months
Santa Ana
high presure air masses over the Great Basin and upper Mojave Desert flow to the low pressure center, taking the path of least resistance by channeling through the mountain passes to the lower coastal elevations, as low pressure off the coast pulls the air mass offshore
Hurricane vs. Cyclone
Atlantic & Pacific Northeast vs. S. Pacific and Indian Ocean
Westerlies
earth’s rotation causes air moving toward the equator to be deflected westward
Trade Wind
Blows toward the equator from northeast or southeast. From high pressure to low pressure equator
Solstices & Equinoxes
Summer: June 21 or 22
Winter: Dec 21 or 22
If the Earth wasn’t tilted
the sun would rise in the east and set in the west, no change, no seasons
parts of the planet higher than 40 degrees would never have the sun overhead
equator would be really hot all the time and other regions would only get some lighting
3 Things that Influence Biogeography
- Earth’s rotation on a tilted axis
- the position of the Earth’s land masses
- Origin - 4.5 billion yo, plants diversifying and land masses changing
Biogeography
the distribution of plants, animals, and other forms of life on Earth, and is heavily influenced by random events like change in climate, topography, etc.
Permean- Triassic
251 million ya
94% of marine
70% of land
Cretaceous
65 million ya
asteroid
Alleles
traits in plants
one of two or more forms of a gene that arise by mutation and are found at the same place on a chromosome
Gametophyte stage
where the plant is haploid and produces gametes
Sporophyte stage
where the plant is diploid and produces spores (sperm) for reproduction
Fragmentation
wide spreading or vining plant grows and establishes its own root system and can survive if detached from the parent
Zygote
when egg and sperm cells are brought together, the diploid fertilized egg is a zygote
Meiosis
shuffles genes (haploid) from one egg, one sperm (gamete)
Mitosis
creates duplicate of a cell’s genes - diploid (2x chromosomes)
Auxins
activates dormant buds, stimulates growth, promotes development of embryos and fruits
Gibberellins
stem elongation, seed germination, flowering
Phytochrome
pigment that detects light for day length
Phototropin
pigment that perceives direction of light
