Yr 2 Unit 2: Ecology B

ecology

the study of interactions between organisms and their environment.

how is a habitat described

ecological location

physical location

type of ecosystem

adaptation examples

marram grass

mangrove trees

shelfords law of tolerance

1. orgs have optimal survival rates for abiotic factors

2. moving from optimum conditions = less survival rate

coral reef tolerance levels

clear, shallow (50m) water for zooxanthellae photosynthesis

16-34.5C temp for coral to not expel zooxanthellae

pH 8-8.3

salinity of 23-42ppt

transect function

A method used to analyze ecological gradients by sampling along a line or path, allowing for examination of species distribution and environmental changes.

niche

role in ecosystem

obligate anaerobes

must have no O2

obligate aerobe

must have O2

facultative aerobe

can have or not have O2

holozoic nutrition

food ingested, digested internally, absorbed, assimilated

mixotroph

can do photosynthesis or hetertrophy

facultative or obligate

mixotroph example

Euglena; freshwater protist

saprotroph

heterotroph

obtain nutrients w external food digestion

decomposers

release enzymes to digest then absorbs nutriente

archaea

microorganisms distinct from bacteria, often found in extreme environments, capable of various metabolic pathways.

phototroph

use light for ATP, no O2 produced

NOT photosynthesis

Chemolithotroph

oxidizes inorganic compounds (ammonia, nitrate, sulfur) for ATP

organotroph

uses org compounds (sugars, fatty acid) for atp

family hominidae

includes great ape family

members = homonids

teeth of herbivores

large

flat

strong jaw

teeth of omnivore

sharp incisor

flat molarfor cutting and grinding food

homofloresiensis and paranthropus robustus

human ancestor

herbivore

plant adaptations for herbivory

physical structure

trichones (sharp) on stinging nettles

ittitating chemicals

grass w tough fibrous leaves

chili plants capsaisin

nicotine toxic in tobacco plant

animal adaptations for herbivory

flat molars

continuously growing teeth

sharp mandibles

serrated edge that cut thru cell walls

muscles to manipulate mandibles

aphid adaptation for herbivory

aphids have stylets (hollow slender tubes) that inert into plant phoem for nutrients

allelopathy

release of chemicals by 1 org to influence germination, growth, survival, reproduction of other orgs

allelopathy example

black walnut trees produce juglone inhibiting tomato growth

antibiotic secretion example

penicillium fungus secretes antibiotic penicillin

inhibits bacteria growth near fungus

predator adaptations

physical: sharp clars/talons, powerful jaw/teeth, camoflage, speed, agility

chemical: venom, toxin

behavioral: pack hunting, ambush

prey adaptations

phsyical: armor/protective covering, swiftness, camoflage, mimicry

chemical: toxic/bad taste, bright color/pattern as warning

behavioral: group travel, swarms, alarm calls, nocturnality/diurnality

canopy tree adaptation

tall trunk

broad crown

broad leaves

liana (woody vine) adaptations

climbing mechaism

rapid growth

flexible/thin stem

large broad leaf

epiphyte adaptations

grow on tree branch (commensalism)

grow on canopy tree

broad flat leaf

flexible growth

strangler epiphyte adaptations

germinate in branch and send down aerial roots surrounding tree

parasitism

shade tolerant plant adaptations

branching

broad leaf

high chlorophyll conc

fundamental niche

niche they could occupy w/o competitionr

realized niche

actual niche

competitive exclusion

no 2 species can have same niche in same area at same time

one will outcompete otherfor resources, leading to extinction of one species.

examples of competitive exclusion

chthamalus barnacles have wider fundamental niche but are excluded from lower tidal zone by faster growing Balamus

• balanus cant survive higher up so chthamalus survives there instead

grey squirrels (invasive) are larger, stronger, faster reproducers and immune to squirrelpox and outcompete red squirrels

genome size

total number dna in cell measured in base pairs

genome size examples

influenza a virus (flu): 13.2 kilobase (Kb)

E coli: 4.6 megabases (Mb)

drosophilia melanogaster: 143.7Mb

homo Saipan: 3.1-3.2 gigabase (Gb)

picea sitchensis (sitka spruce): 20.5 Gb

genome sequencing use

evolution studies

personalized medicine

DNA barcode

a short genetic sequence used to identify species, often from mitochondrial DNA.

requirements for natural selection

variation

overproduction

competition for limited resources

differential survival and reproduction

survival of fittest

heritability of traits

gene pool

all genes and alleles in population

human allele variation ex

ABO blood group have diff regional variation

O blood more in Africa

Hardy Weinburg equillibrium

when allele and genotype frequency in pop remain consistent from gen to gen

allele frequency equation

p + q = 1

p is dom allele freq

q is recess allele freq

genotype freq eq

p² + 2pq + q² = 1

p is dom allele freq

q is recess allele freq

assumptions of hardy weinburg

pop is large

no immigration/emmigration

random mating

no mutation

no natural selection

if allele freq in pop change…

the population is evolving, indicating potential influences such as selection, mutation, or migration.