Habitats, Biomes, & Populations

Describe habitat: physical area where a species is found ; Includes information about- geographical area, physical location, food, water, shelter availability, ecosystem, biotic and abiotic factors

Describe abiotic factors and provide examples: nonliving aspects of environment ; ex. Soil, pH, light, water, inorganic nutrients, space

Describe biotic factors and provide examples: living components of the environment. ; Ex: competition, symbiosis, predators

Describe the effects of limiting factors on communities. Organisms adapt to limiting factors in their environment. Determines species present.

Provide an example of a plant found on the sand dunes and outline its adaptations. Marram Grass- long dense roots, salt tolerance, & drought tolerance.

Provide an example of a plant found in the mangrove forest and outline its adaptations. Mangrove Trees- Pneumatophores, stilt roots, & halophyte.

Describe the use of transects.

Method used to determine effects of limiting factor on a sample of organisms in area

Most common type used is Line Transect

Help determine zone of tolerance

Outline conditions needed for coral reef formation.

Water depth (2-45m)

Stable salinity

Temperature (23-29C)

pH (*8-8.4)

Clear water

List human activities that destroy coral reefs.

Global Warming

Overfishing

Pollution

Coastal Development

Describe biomes and what shapes them.

Biomes are communities shaped by common environmental conditions.

shaped by temperature and precipitation.

Plants and animals share common traits from convergent evolution.

Distinguish between biomes and ecosystems.

Ecosystems are smaller, Biomes are larger.

Ecosystem more specifically defined, biome more broadly.

Biomes are generally affected by their latitude.

Outline the characteristics of a named biome

Describe adaptations to the desert biome

Describe adaptations to the tropical rainforest biome

Describe Species. A group of individuals that produce fertile offspring.

Describe population. group of organisms of same species found in a specific area

share a common gene pool

generally reproductively isolated

Outline the 3 different ways species distribute themselves within a population.

Random: plentiful resources & little social interaction

Uniform: intraspecific competition

Clumped: social & most often seen

List the 4 factors that influence population size.

natality (birth)

mortality (deaths)

immigration (move in from migration)

emigration (move out from migration)

Population size= (N+I) - (M+E)

Describe carrying capacity. maximum population size the environment can sustain (“K”)

Describe population density. number of individuals per unit area

how “packed” organisms are can impact population size

Describe density dependent factors. Impact size as population density increases

Negative feedback mechanisms

Regulate population size

Keep close to carrying capacity

List density dependent factors. Impact population size regardless of its density

Factors are external to populations

Sudden and drastic change

State the two type of population growth graphs/curve.

Exponential Growth Curve

ideal conditions and unlimited resources

creates j shaped curve

ex: bacteria in laboratory or protected species

Logistic Sigmoid growth curve:

- more realistic Creates S shaped curve

- Density- dependent factors limit populations

Fluctuates around carrying capacity

State which curve is more realistic. Logistic is more realistic because it accounts for the limitations of resources and environmental factors.

Describe what intraspecific means. Intraspecific interactions are interactions between individuals of the same species.

State the two types of intraspecific interactions in populations.

Cooperative: These interactions benefit both individuals, such as cooperative hunting or raising young.

Competitive: These interactions harm both individuals, such as competition for resources like food, water, or territory.

Describe the sigmoid growth curve.

The sigmoid growth curve is another name for the S-shaped curve, which represents logistic growth.

It illustrates how a population's growth slows down as it approaches its carrying capacity due to limited resources.

Outline a case study that illustrates sigmoid growth.

Sheep Introduced to Tasmania: Sheep were introduced to Tasmania, and initially, their population grew rapidly (exponentially). However, as resources became limited (food, water, space), the growth rate slowed down, and the population stabilized around the carrying capacity of the environment, resulting in an S-shaped curve.

State the 2 ways to estimate population size.

Mark-Recapture Method:

This method involves capturing, marking, and releasing a sample of individuals, then recapturing a second sample and observing the proportion of marked individuals in the second sample to estimate the total population size.

Quadrat Sampling

Distinguish between sessile and motile organisms.

Sessile: Organisms that are attached to a substrate and cannot move freely, such as barnacles or corals.

Motile: Organisms that can move freely, such as fish, birds, or mammals.

State a method to calculate population size of sessile organisms. Quadrat sampling

Outline Quadrat sampling.

This method involves randomly placing quadrats (squares) in a study area and counting the number of individuals within each quadrat to estimate the population density, which can then be extrapolated to the entire area.

Describe standard deviation.

High

Show major differences between quadrats

Abundance is different throughout sample area

Low

All close to sample number (mean)

Abundance is same throughout sample area

State the method to calculate population size of motile organisms. Lincoln Index

Outline Lincoln Index.

Lincoln Index:

“capture - mark - release - recapture” method

capture

tag (M)

release

time to mix back with population

recapture

recaptured animals (R)

total number recapture (N)

State the nickname ”common name” for Lincoln Index. “capture - mark - release - recapture”

State the formula for Lincoln Index. N = (n1 * n2) / m2,

N: estimated population size

n1: #’s of individuals marked in the first sample

n2: total # of individuals captured in the second sample

m2: # of marked individuals recaptured in the second sample

Be able to complete a lincoln index problem

Unit Assessment Information:

Coming soon

Data based question