What is the name for the study of the interactions between organisms and their surroundings?
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Ecology
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What is the name for the study of the interactions between organisms and their surroundings?
Ecology
What term describes a group of individuals of the same species that live in the same area?
Population
In biology, what is a group of different species of organisms that interact together in a given space called?
Community
What term encompasses all the living and nonliving components interacting in a given area?
Ecosystem
What is the term for the natural home or environment of an animal, plant, or other organism?
Habitat
What is an individual animal, plant, or single-celled life form called?
Organism
What term is used to describe the variety of life in a given ecosystem?
Biodiversity
What is the first (largest) division of living things in the biological classification system?
Kingdoms
What are the five kingdoms used to classify living organisms?
Animals, plants, fungi, protoctists, and prokaryotes.
What is the sub-group level that a Kingdom is divided into, such as "Chordata" in the animal kingdom?
Phylum
In biological classification, into what sub-division is a Phylum further divided?
Class
To which phylum do animals that have a backbone belong?
Chordata
Into which five categories is the Chordata phylum divided at the "Class" level?
Mammals, birds, amphibians, fish, and reptiles.
What term is used to describe organisms like animals that are made up of many cells?
Multicellular
Which organelle in an animal cell contains the genetic material (DNA) and controls the cell's activities?
Nucleus
What is the name of the liquid that makes up most of the cell where chemical reactions happen?
Cytoplasm
What is the name of the flexible outer layer of a cell that controls the passage of substances into and out of the cell?
Cell membrane
In which part of the cell does most respiration occur to release energy?
Mitochondria
What are the tiny structures in a cell where proteins are produced?
Ribosomes
From what fiber is the plant cell wall made?
Cellulose
Which plant cell organelle contains the green pigment chlorophyll and is the site of photosynthesis?
Chloroplasts
What part of the plant cell is filled with cell sap and helps maintain water balance?
Vacuole
What is the word equation for photosynthesis?
Carbon dioxide + water → Glucose + Oxygen
What is the chemical equation for photosynthesis?
(6CO_{2} + 6H_{2}O \rightarrow C_{6}H_{12}O_{6} + 6O_{2})
What two features do animals usually have that distinguish them from other multicellular organisms like plants?
Nervous co-ordination and the ability to move.
Compare the carbohydrate storage of plants and animals.
Plants store carbohydrate as starch or sucrose; animals store it as glycogen.
What is the fungal cell wall made of?
Chitin
What is the process called when fungi feed by extracellular secretion of digestive enzymes onto food and absorption of the products?
Saprotrophic nutrition
What are the thread-like structures that organize the body of multicellular fungi?
Hyphae (singular: hypha)
What is the network of branching hyphae in a multicellular fungus called?
Mycelium
What is an example of a multicellular fungus mentioned in the study guide?
Mucor
What is an example of a single-celled fungus?
Yeast
What is the nickname often given to the Protoctist kingdom because of its diverse group of organisms?
Dustbin kingdom
Which microscopic, single-celled protoctist lives in pond water and has features like an animal cell?
Amoeba
What is an example of a protoctist that has chloroplasts and is similar to a plant cell?
Chlorella (or Algae)
What pathogenic protoctist is responsible for causing malaria?
Plasmodium
What reproductive structures are contained in a mushroom or toadstool that enable it to reproduce?
Spores
Like animals, what do fungi typically store their carbohydrate as?
Glycogen
What is the name for cells that contain a nucleus, such as those in plants, animals, fungi, and protoctists?
Eukaryotic cells
What term refers to simpler cells that do not contain a nucleus, with bacteria being the primary example?
Prokaryotic cells
Instead of a nucleus, what does a bacterium contain to store its genetic information?
Circular chromosome of DNA (and plasmids)
What are the small, circular strands of DNA found in bacterial cytoplasm called?
Plasmids
What rod-shaped bacterium is used in the production of yoghurt from milk?
Lactobacillus bulgaricus
What spherical bacterium acts as a pathogen causing pneumonia?
Pneumococcus
What are three cellular components that bacteria share with plant cells?
Cell membrane, cytoplasm, and cell wall.
What is the cellular organization of all bacteria?
Unicellular (single-celled)
What are two examples of organisms that belong to the Prokaryote kingdom?
Bacteria and blue-green algae.
What is the name for a list of organisms in a habitat that shows their feeding relationship?
Food chain
What do the arrows in a food chain represent?
The transfer of energy in food.
What is the name for the different stages in a food chain?
Trophic levels
What is the name for an organism, like a green plant, that can photosynthesize and produce its own food at the start of a food chain?
Producer
What term is given to an animal that eats the producer in a food chain?
Primary consumer
What is an organism that eats a primary consumer called?
Secondary consumer
What is an organism that eats a secondary consumer called?
Tertiary consumer
What is an animal that eats only plants called?
Herbivore
What is an animal that eats other animals called?
Carnivore
What term describes an animal that eats both plants and animals?
Omnivore
What is formed when many food chains in a habitat become intertwined and interconnected?
Food web
What can happen in a food web when there is a change in the population of one organism?
A knock-on effect on the population of other organisms within the same web.
What term describes interactions associated with living things that can affect biodiversity, such as food availability, predation, and disease?
Biotic factors
What term refers to physical or chemical non-living factors that affect biodiversity, like temperature, sunlight, and soil pH?
Abiotic factors
What is the name for bacteria and fungi that break down dead organisms?
Decomposers
By what process do decomposers break down dead matter, involving the release of enzymes and absorption of broken down substances?
Saprotrophic nutrition
What is the vital role of decomposers in an ecosystem?
They recycle matter so that nutrients can be absorbed by plants.
How does grazing (a biotic factor) affect biodiversity?
Too little leads to dominant plants outcompeting others; too much reduces the number of species. Both decrease biodiversity.
Explain how the reduction of predators (a biotic factor) can affect biodiversity.
A reduction in predators can lead to overgrazing by prey, which reduces biodiversity.
List six abiotic factors that can affect biodiversity.
Temperature, sunlight, water, soil pH, soil moisture, and pollution.
List six biotic factors that can affect the biodiversity of an ecosystem.
Food availability, competition, grazing, predation, disease, and nesting availability.
What is the name of the square frame, usually 1 meter in length and width, used for sampling plants or slow-moving animals?
Quadrat
What are two critical requirements for using a quadrat to get an accurate sample?
Random placement and representative sample size (many repetitions).
What is a common limitation of using a quadrat for counting organisms?
Human judgement (e.g., whether to count a plant partially in the frame).
Besides counting organisms, what else can a quadrat split into smaller squares allow scientists to calculate?
Percentage coverage
How should the position of a quadrat be determined to ensure an unbiased sample?
Randomly generated coordinates.
Typically, how many times should a quadrat be placed to sample an area?
10 - 15 times.
Once data is collected from several quadrats, what is the first mathematical step in estimating the total population?
Mean (average) number per quadrat.
Describe the final step to calculate the total number of organisms in a field using quadrat data.
Multiply the mean (average) per quadrat by the total area (scaled by the quadrat size).
If a field is 15 m wide and 10 m long, what is its total area?
150 (m^{2})
What is the process that shows how atoms of carbon are recycled between living organisms and the environment?
Carbon Cycle
Which process in the carbon cycle removes carbon dioxide from the atmosphere?
Photosynthesis
By what process do living organisms break down carbon compounds for energy and release carbon dioxide back into the atmosphere?
Respiration
What process releases carbon dioxide into the atmosphere when fossil fuels are burned?
Combustion
How are carbon atoms passed from one organism to another along a food chain?
Feeding
What role do decomposers play in the carbon cycle?
They break down dead organisms and return carbon to the atmosphere as carbon dioxide via respiration.
If conditions are not suitable for decomposition, what might dead organisms eventually become over millions of years?
Fossil fuels
List four major biological molecules that contain the essential element carbon.
Carbohydrates, proteins, DNA, and lipids.
What are the three main elements found in fertilisers that help plant growth?
Nitrogen, Phosphorus, Potassium (NPK)
What property must fertiliser compounds have so they can be absorbed by plant roots?
Solubility in water.
What type of water pollution is caused by the addition of sewage or excess fertiliser nutrients into a waterway?
Eutrophication
What is the rapid growth of algae in a river or lake caused by extra nutrients called?
Algal bloom
Explain one reason why an algal bloom leads to lower oxygen levels in the water.
The algae block sunlight, preventing plants at the bottom of the water from photosynthesizing.
Besides blocked sunlight, what other factor depletes oxygen during eutrophication?
The bacteria that decompose dead algae use up oxygen in the water.
Which two types of compounds found in fertilisers are the primary cause of eutrophication when they leach into waterways?
Nitrates and phosphates.
Outline the five main stages of eutrophication.
