Definitions
Keystone species
an organism that helps hold the system together. Without its keystone species, ecosystems would look very different
Primary vs secondary succession
Primary : no rocks or plants present
Secondary : happens where there is existing rocks and soil. Faster
A clownfish lives among the tentacles of a sea anemone. The fish gets protection from predators, and the anemone gets cleaned of parasites and food scraps.
Mutualism
Nitrogen gas (N₂) from the atmosphere can be directly used by most plants.
False
Can two species live in the same habitat without competing? Explain your reasoning.
Yes , if they occupy different niches
Ecosystem
All the biotic and abiotic factors together
Provisional vs cultural service
Provisional : provides food, water, oil , gas
Cultrual : rest and relax. Hiking , canoing..etc
A tapeworm lives inside the intestines of a dog and absorbs nutrients from the food the dog eats, causing the dog to lose weight.
Parasitism
Deforestation helps reduce carbon dioxide levels in the atmosphere.
False
How does predation help keep populations balanced in an ecosystem?
More predators kill more prey, which, along with food scarcity, decreases the population. When prey becomes scarcer, the predator population declines until prey is again more abundant. Therefore, the two balance each other.
Pioneer species
First species to colonize habitats
Open system vs closed system
open system : energy and matter can enter and exit
closed system : only energy can enter and exit but matter CAN'T
Two species of grass grow in the same area and compete for sunlight and water.
Competition
Floods and forest fires can trigger secondary succession.
True
Why is nitrogen important for living organisms, even though we can’t use the nitrogen gas in the air directly?
To make protein for growth
Law of conservation of energy
Energy is not created or destroyed. It is only transferred.
keystone species : an organism that helps hold the system together. Without its keystone species, ecosystems would look very different
invasive species : animals or plants from another region of the world that don't belong in their new environment.
A remora fish attaches to a shark and eats scraps of food the shark leaves behind. The shark is unaffected.
Commensalism
Higher biodiversity usually makes an ecosystem more stable and resilient.
True
Why is it important to protect biodiversity even in small or less well-known ecosystems?
Because more biodiveristy , means higher survival rate since they are able to adapt ( survive + reproduce)to new , changing environments.
Succession
a series of progressive changes in the in community over time.
Carbon cycle vs nitrogen cycle
Carbon cycle : where carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of Earth.
Nitrogen cycle : process through which nitrogen is converted into many forms, passing from the atmosphere to the soil to organism and back into the atmosphere.
A snake captures a mouse to eat.
Predation
All ecosystems on Earth have the same level of biodiversity.
False
What are some ways humans can protect biodiversity, and what challenges might we face in doing so?
Humans can protect biodiversity by : 1. creating protected areas, 2. using natural resources sustainably, 3. restoring habitats.
challenges include : 1. economic pressures from industries, 2.population growth that leads to habitat loss, 3. lack of public awareness.