APES Unit 3 Review

Populations Distribution

individuals can be distributed or dispersed in an area or volume

3 Populations Distribution Patterns:

Clumped, Uniform, Random

Why Clumped?

• to hunt easier

• for protection from predators

• to share the workload

• Creatures clump around resources *

• easier to find mates

Why uniform?

• animals that are territorial

Why random?

• Their distribution is random (plants and their seeds)

What is the formula for population growth or decline?

Change = (B+I) - (D+E)

Age Structure Diagram

a visual representation of the number of individuals within specific age groups for a country, typically expressed for males and females; 0-14 pre reproductive, 15-44 reproductive, 45-85+ post reproductive

How do you calculate population density?

in population/the area = density

Exponential Population Growth

Biotic potential, intrinsic rate of increase, r= the growth rate of the population if it had unlimited resources; reproduce early, short generation times, long reproductive life, lots of offspring, not realistic,, populations can't grow indefinitely

Environmental resistance

all the combined limiting factors that limit the growth of a population

Density Dependent factors

the size of the population will influence an individual's probability of survival; ex: disease, competition, predation

Density Independent factors

the size of the population has no effect on the individual's probability of survival; ex: floods, fire, pollution, habitat

Carrying Capacity

maximum number of a certain species that a certain habitat can sustain indefinitely without degrading it

Carrying capacity equations

Biotic potential + (Environmental Resistance) = Carrying Capacity

Logistic population growth

A model describing population growth that levels off as population size approaches carrying capacity

Abiotic reproduction

• Plants, bacteria, and sponges

• It's easy to do

• Faster than sexual reproduction

• Less Genetic Diversity

Sexual Reproduction

• Genetic variability, offspring protection

• Males don't give birth

• Increase genetic errors

• Courtship is costly

r-selected species

• many small offspring

• no parental care

• adapt to unstable conditions

• generalists

• low ability to compete

• early successional species

• population fluctuates

K-selected species

• fewer large offspring

• parental care

• used to stability

• specialist

• can compete

• late successional species

• steady population

Survivorship curve

a graph that represents the distinct patterns of species survival as a function of age; late loss (k), constant loss, early loss (r)

Why did human exponential growth occur?

• Human exponential growth happened because more people survived due to modern medicines such as vaccines and antibiotics

• Human exponential growth happened because the food supply got better and increased due to advances in agricultural technologies such as GMOs

• Human exponential growth occured because we as humans can expand into a vast variety of biomes making it easier for us to spread out into unclaimed territory

Crude Birth Rate

Number of births per 1000 people in a population per year

Crude Death Rate

Number of deaths per 1000 people in a population per year

Crude migration rate

Number of migrants/ 1000

Natural Increase in a population

CBR-CDR = Natural +/-

% change with crude numbers

CBR-CDR/10

Doubling Time (Rule of 70)

Annual growth rate = 70/doubling time

Doubling time = 70/% growth

Population growth with real numbers

• New population = (B+I) - (D+E)

• New- Old/Old multiplied by 100 = percent change

Fertility

the number of children born to a woman in her entire lifetime

Total Fertility Rate:

the average number of children a typical woman has

Replacement Level Fertility

the number of children a couple must have in order to replace themselves

What affects birth rates and fertility?

Increase:

• Children as labor

• Culture/Norms

• Infant Mortality

• Religious Beliefs

Decrease:

• Private and Public pension

• Culture/Norms

• Education and Employment for women

• Average age at marriage

• Availability to legal abortions

• Availability of birth control

• Cost of education/raising

Death rates have declined because of...

Increased food supplies, better nutrition.

Advances in medicine.

Improved sanitation and personal hygiene.

Safer water supplies.

Best indicators of overall health?

Life expectancy and infant mortality rate

The Demographic Transition

Phenomenon and theory which refers to the historical shift from high birth and death rates to low birth and death rates as societies attain more technologies, education, and economic developments

Demographic Traps

When countries get stuck in stage 2; death rate goes down, birth rate doesn't; ex. African HIV/AIDS epidemic

Stage 1

Pre-industrial; birth and death rates high; Total Fertility Rate: >2.0

Stage 2

Transitional; death rate drops; cultural lag time occurs; Total Fertility Rate= > 2.0

Stage 3

Industrial; birth rate drops; total fertility rate= > 2.0

Stage 4

post-industrial, Birth rate = death rate, total fertility rate= 2.0

Stage 5

post-industrial, Birth rate is lower than death rate, total fertility rate= < 2.0

Probability

how likely it is that harm will be suffered from a hazard

Risk assessment

the scientific assessment of how much harm a particular hazard can cause to human health or the environment

Risk Management

whether or how to reduce the risk to what level at what cost

Types of Risks

1. Biological Hazards

2. Chemical Hazards

3. Physical Hazards

4. Cultural Hazards

Biological Hazard

Disease

Non-transmissable diseases

diseases not caused by living organisms cannont spread from one person to another; ex: cardiovascular disorder, asthma, malnutrition

Transmissible/infectious diseases

caused by living organisms such as bacteria and viruses can spread from person to person; top 4 people die from: 1) diarrheal diseases 2) Tuberculosis 3) HIV/AIDS 4) Malaria

Transmissible disease caused by fleas and how to avoid it

Plague, Rat Traps

Transmissible diseases caused by mosquitoes and how to avoid them

Zika, West Nile Virus, Malaria; bug spray, wear long clothes, mosquito net

Transmissible diseases caused by someone coughing on you and how to avoid them

Tuberculosis, Severe Acute Respiratory Syndrome, Middle East Respiratory Syndrome; Wear a mask and wash your hands if exposed

Transmissible diseased caused by infected water and how to avoid them

Cholera and Dysentery; filter/boil your water

Chemical hazards

can harm because they are flammable, explosive, irritate, interfere with oxygen uptake, induce allergic reactions

Mutagens

chemicals or forms of radiation that can mutate DNA (nitrites in hot dogs)

Teratogens

cause harm or birth defects to a fetus or embryo (alcohol, DDT,lead)

Carcinogens

chemicals or radiation that can cause or promote cancer (tumors)