2.D.4

Essential knowledge 2.D.1: All biological systems from cells and organisms to

populations, communities and ecosystems are affected by complex biotic and abiotic interactions involving exchange of matter and free energy.

1.Provide examples of how biotic and abiotic factors affect organism behavior,

community interactions, and ecosystem structure. Utilize the following examples

in your responses:

○ Water availability

If there is not enough water in a environment (abiotic), then the organisms living there will die.

○ Sunlight

Plants (biotic) that receive little to no sunlight (abiotic) will die because they cannot undergo photosynthesis. 

○ Symbiosis (mutualism, commensalism, parasitism)

Symbiosis; Clown fish are protected by the anemone.

Mutualism: Bees pollinating a plant, both benefit

Commensalism: Barnacles living on a whale, one is benefiting but neither hurts the other.

Parasitism: Tapeworms living inside of a human, the parasite ( tapeworm) is receiving nourishment from the host.

○ Predator–prey relationships

A mongoose eating a snake is a example of a predator-prey relationship.

○ Water and nutrient availability, temperature, salinity, pH

If there is low resources and water (abiotic), then organisms in a environment will die

○ Availability of nesting materials and sites

If birds want to nest on a cliff (biotic), the geography (abiotic) may not be large enough to support all of the birds.

○ Food chains and food webs

If wolves were moved from a ecosystem, then the populations of the surrounding organisms like beavers, foxes, and trees would decrease or increase dramatically

○ Species diversity

In a diverse ecosystem, if you remove a species from a environment, then populations of other species will be greatly effected.

○ Population density

If there are is a large amount of fish in a small lake, then the fish will have to compete with the other fish for the limited resources.

○ Algal blooms

In the St. Johns river, the water is warm and the sunlight is abundant and causes alga to boom and massive fish die off during the night because there is not enough of water of oxygen

Essential knowledge 2.D.2: Homeostatic mechanisms reflect both common

ancestry and divergence due to adaptation in different environments.

1.     How do homeostatic mechanisms relate to evolution?

Homeostatic mechanisms relate to evolution because they reflect a common ancestry in all organisms

2. How is the concept of common ancestry supposed by continuity in homeostatic

mechanisms.

The concept of common ancestry is supported by continuity in homeostatic mechanisms because every organism has a response but they have different responses to different environmental conditions

2.     How do changes in environmental conditions affect this continuity.

Changes in a environmental condition affects continuity by how a organism responds to that condition

4. Explain how the following mechanisms are used for obtaining nutrients and eliminating wastes.

 

Flatworm excretory system

Stomata

○ Gas exchange in aquatic and terrestrial plants

Both aquatic and terrestrial plants both use gas exchange by diffusion however both of them have a different way of acquiring water. In terrestrial plants get water through openings called stomata, while aquatic plants exchange gas through direct diffusion in surrounding water.

○ Digestive mechanisms in animals such as food vacuoles, gastrovascular cavities, one-way digestive systems

Protists take food in through phagocytosis and store the food in a food vacuole. In a gastro vascular system, there is one opening that take nutrients and gases from the environment. A one-way digestive system there is one opening for food and another opening for waste.

○ Respiratory systems of aquatic and terrestrial animals

Lungs

In aquatic animals, gills are used to filter water and for the animal to get oxygen. In land animals, oxygen enters the body through tubes in insets, vertebrates have internal lungs and mammals and amphibians use positive pressure breathing to force air down the trachea.

○ Nitrogenous waste production and elimination in aquatic and terrestrial animals

All organisms produce and eliminate waste in aquatic and terrestrial animals.

5. Explain how homeostatic control systems in species of microbes, plants an animals support common ancestry. Use the following to help illustrate your explanation:

○ Excretory systems in flatworms, earthworms and vertebrates

Flat worms regulate the excretory system by protonephridia. They are branching canals that allow waste out of their body. Earth worms go through metanephridia to release toxic urea. Vertebrates use kidneys to release waste.  Shows that all organisms release waste

○ Osmoregulation in bacteria, fish and protists

Osmoregulation shows that all organisms go through this process.

○ Osmoregulation in aquatic and terrestrial plants

Both plants and animals have openings to balance gas

○ Circulatory systems in fish, amphibians and mammals

All organisms need to transport nutrients through blood to all their cells

○ Thermoregulation in aquatic and terrestrial animals (countercurrent exchange)

All organisms need a flow to keep homeostasis in their body

Essential knowledge 2.D.3: Biological systems are affected by disruptions to their dynamic homeostasis.

1. How do disruptions at the molecular and cellular levels affect the health of the organism? Use the following to explain your answer:

○ Physiological responses to toxic substances

Organisms that are expose to toxins in food, water, or in the air can be affected by causing cancer in organisms and can threaten wildlife.

○ Dehydration

If a organism undergoes dehydration, the organism can experience darker urine, respiration increase, delirium and then death.

○ Immunological responses to pathogens, toxins and allergens

If a organism is not able to fight off an infection, such as a person having HIV, then any pathogen can invade the body and the body will not respond to the pathogen.

2. Provide examples of how disruptions to ecosystems can affect the dynamics of the  ecosystem. Utilize the following examples in your responses:

● Invasive and/or eruptive species

An invasive species can cause other species in the environment to start to compete with aggressive species for resources

● Human impact

Farmland can reduce biological activity

● Hurricanes, floods, earthquakes, volcanoes, fires

Natural disasters can disrupt a ecosystem by killing trees, organisms, and reducing resources in a ecosystem

● Water limitation

Limited water will cause organisms to compete with each other and can cause death to those that aren’t fit enough.

● Salination

If a soil does not have a proper amount of nutrients, then plants will grow slowly or will not be able to live in that environment

Essential knowledge 2.D.4: Plants and animals have a variety of chemical

defenses against infections that affect dynamic homeostasis.

1.     Explain how plants, invertebrates and vertebrates have multiple, nonspecific (innate) immune responses. Include how they work and structures/chemicals involved.

Invertebrates use their exoskeleton and the digestive system to fight off pathogens. Hemocytes are found in hemolymh of insects. They engulf pathogens through phagocytosis. Plants use PRRs that detect microorganism associated molecular patterns (MAMPs). Once the PRRs have detected MAMPS they will begin systemic acquired resistance and destroy infect and adjacent cells. Vertebrates have multiple types of non-specific responses such as skin, mucus and lysozymes. These responses stop pathogens from entering the body and lysozymes.

2. Describe mammalian specific immune responses.

• Describe the two types of specific responses in the Mammalian

immune system

• In the cell-mediated response, what is the role of cytotoxic T cells?

• In the humoral response, what is the role of B cells?

In cell mediated response cytoxic T cells attach to a pathogen and turn into a killer T cell, which will kill the pathogen. In the humoral response, B cells create antibodies to shut down a pathogen so a macrophage could digest it.

3. Explain how antigens and antibodies work together.

• What is an antibody?

• How does a second exposure to an antigen differ from the primary exposure?

An antibody is Y shaped protein that identifies and neutralizes pathogens.  If a person was exposed to the antigen a second time, Memory cells would know what the specific antigen is an will be able to clone B and T cells much faster than in a primary exposure