Biology

Question 1

Non infectious diseases

Answer 1

disease that is not caused by pathogens but rather by inherited, nutritional, or environmental conditions

Question 2

infectious diseases

Answer 2

caused by pathogens that enter the body and multiply

Question 3

What are the five major groups of pathogens and an example of a disease

Answer 3

Viruses - ebola

Bacteria - salmonella

fungi - ringworm

protozoa - plasmodium

multicellular parasites - tapeworm

Question 4

What are the modes of disease transmission

Answer 4

Airborne, waterborne, insect borne, direct contact, sexually transmitted, foodborne

Question 5

prevention strategies for airborne diseases

Answer 5

wearing masks, social distancing, quarantine

Question 6

prevention strategies for waterborne diseases

Answer 6

purification tablets, boiling water before drinking, water treatment

Question 7

prevention strategies for insect borne diseases

Answer 7

insect repellant, long sleeve clothing, removal of stagnant water

Question 8

prevention strategies for direct contact

Answer 8

clean surfaces, washing hands, no physical contact, quarantine

Question 9

prevention strategies for sexually transmitted diseases

Answer 9

protection, abstinence

Question 10

prevention strategies for food borne diseases

Answer 10

proper storage (refrigerate), avoid cross contamination

Question 11

Are developing countries more susceptible to epidemics and pandemics of infectious diseases?

Answer 11

Yes, due to overcrowding, malnutrition, cultural attitudes, practices and inadequate public health systems

Question 12

Describe the first line of defense

Answer 12

non specific, prevents pathogens from entering the body through physical and chemical attributes

physical- skin, blocks entry of pathogens, mucus and cillia in nose and lungs, traps pathogens then removed by sneezing or coughing

chemical - stomach acid, destroys pathogens, tears, break down bacteria cell walls, mucus, can destroy and trap pathogens

Question 13

describe the second line of defense

Answer 13

non specific, the response once pathogens enter the body, it causes the inflammatory response

1) damaged and infected tissue releases chemical signals

2) blood vessels dilate and plasma carries white blood cells (neutrophils and microphages) and platelets to the infected area

3) neutrophils release chemicals to damage and destroy pathogens

4) microphages engulf and destroy pathogens

5) processes continue until there is no more damaged tissue to release signals

Question 14

describe the third line of defense

Answer 14

specific, identifies specific microorganisms

1) pathogens enter the body and the third line of defense begins identifying pathogens

2) B lymphocytes (B cells), type of white blood cells, move through the blood looking for pathogens

3) each pathogen has a specific marker called an antigen. B cells produce designer antibodies. The antibodies attach to there matching antigen and tags the pathogen for destruction.

4) once the infection is cleared, some B cells become memory cells. If the body is infected with the same pathogens again, the memory cells produce antibodies quickly and in larger numbers resulting in a faster response

Question 15

How do vaccines build immunity against pathogens

Answer 15

Vaccines help develop immunity by imitating an infection, they contain weakened or dead pathogens that are injected in order to stimulate the immune system. This allows the body to create memory cells via the 3 lines of defense creating a faster response

Question 16

What are some public health measures that can affect disease incidence

Answer 16

improved sanitation, mass vaccination, lockdowns, mask wearing, international and local travel restrictions, social distancing

Question 17

Abiotic factors

Answer 17

non - living factors that effect survival (eg. temperature, salinity, atmosphere, PH scale)

Question 18

Biotic Factors

Answer 18

interactions/activities between living things that affect survival (eg. disease, feeding, relationships, competition)

Question 19

What are the three types of species interactions

Answer 19

symbiosis - interspecific interaction in which different species live together in long term relationships

competition - where organisms struggle for the same resource (can be between same species of different)

predation - where one organism actively hunts another

Question 20

what are the three major types of symbiosis

Answer 20

mutualism - both organisms benefit

commensalism - one benefits and the other is not affected

parasitism - one benefits (parasite) other is harmed (host)

Question 21

word equation for photosynthesis

Answer 21

Carbon dioxide + water -> energy rich foods + oxygen

Question 22

chemical equation for photosynthesis

Answer 22

6CO2 + 6H2O ——> C6H12O6 + 6O2

Question 23

word equation for cellular respiration

Answer 23

energy rich foods + oxygen –> carbon dioxide + water + energy (ATP)

Question 24

chemical equation for cellular respiration

Answer 24

C6H12O6 + 6O2 –> 6CO2 + 6H2O + ATP

Question 25

The processes of the carbon cycle

Answer 25

photosynthesis, consumption and assimilation, respiration and decomposition, combustion

Question 26

The processes of the nitrogen cycle

Answer 26

ammonification, nitrogen fixation, nitrification, denitrification, assimilation

Question 27

bioaccumulation, negative impacts and ways to reduce impacts

Answer 27

the gradual accumulation of pollutants such as pesticides, plastics or other chemicals through the lifetime of an individual organism negative impacts - many pollutants are poisonous or toxic and cause weakness, illness, sterility or death, this then leads to imbalances within ecosystems and loss of biodiversity ways to reduce impacts - limit amount of pollutants entering ecosystems through good waste management reduce use of persistent chemicals like DDT remove pollutants already in ecosystems

Question 28

Biomagnification, negative impacts and ways to reduce impacts

Answer 28

is the increase in the concentration of a pollutant from one trophic level to another, the higher an animal is on the food chain, the greater the concentration which accumulates negative impacts - amplifies the effects of bioaccumulation leading to imbalance in ecosystems and loss of biodiversity ways to reduce impacts - same as bioaccumulation and raising public awareness of health issues arising from eating contaminated organisms

Question 29

deforestation, negative impacts and the ways to reduce impacts

Answer 29

the removal of native vegetation when the predominant plant is trees over 2 meters in height negative impacts - wide scale land degradation, loss of nutrients increased levels of soil erosion and levels of salinity loss of biodiversity, trees are habitats for a wide range of organisms global warming, trees remove carbon dioxide from the atmosphere, fewer trees means more carbon dioxide ways to reduce impacts - decrease the amount of deforestation, replant trees

Question 30

enhanced global warming, negative effects and ways to reduce impacts

Answer 30

human actions add extra greenhouse gases, causing the earth's average temperature to rise, natural global warming is greenhouse gases trap heat in the earth's atmosphere allowing human inhabitance negative impacts - habitat loss (ice melts and damage to coral reefs) more severe weather events ways to reduce impacts - reduce green house gas emissions by using alternative energy sources reduce deforestation and increases reforestation

Question 31

bacteria

Answer 31

larger, cellular, can reproduce on their own, antibiotics are effective against them

Question 32

viruses

Answer 32

smaller, can only replecate in a host cell, non cellular, antibiotics are not effective against them

Question 33

similarities between viruses and bacteria

Answer 33

types of pathogens that cause infectious disease

Question 34

Describe the carbon cycle

Answer 34

photosynthesis - CO2 is removed from the air and enters the food chain via photosynthesis in producers consumption and assimilation - carbon is then transferred between organisms (passes along food chains through organic matter via feeding and assimilation into biomass) respiration and decomposition -carbon leaves organisms and is added to the air as a result of cellular respiration (excreted CO2) and also during decomposition (CO2 and CH4) some carbon leaves organisms in faeces. combustion - burning wood and fossil fuels adds carbon into the air

Question 35

explain the nitrogen cycle

Answer 35

ammonification - the production of ammonia (NH3) from proteins in dead organisms and urea in urine decomposers - breakdown dead material and waste nitrogen fixation - the conversion of nitrogen gas into nitrogen compounds (eg. ammonia (NH3) and nitrate (NO3)) nitrogen fixing bacteria - convert atmospheric nitrogen into ammonia or nitrates. They are located in soil or live symbiotically in the roots of nodules of some plants nitrification - the conversion of ammonia (NH3) into nitrites (NO2) and then into nitrates (NO3) nitrifying bacteria - converts ammonia and nitrites into nitrates denitrification - the conversion of soil nitrates into nitrogen gas (N2) denitrifying bacteria - coverts nitrates and nitrites back into atmospheric nitrogen (N2) assimilation - movement of nitrogen from the soil into producers and then along food chains via feeding and from the soil (animals get nitrogen from eating food)