Ecosystems & Energy Flow
A shallow pond contains water lilies, minnows, frogs, and decomposers. What is the original source of energy for all of these living organisms?
The Sun/Sunlight
A meteorologist notes that a high-pressure system is moving into North Carolina. What type of weather forecast should citizens expect for the day?
Fair weather, clear/sunny skies, and light winds ("Happy High")
A student places a metal spoon and a plastic spoon into a mug of boiling hot cocoa. After two minutes, which spoon will feel much hotter to the touch, and why?
The metal spoon, because metal is an excellent conductor that allows heat to pass through it easily.
A soccer ball is kicked across a thick, grassy field. Even though no one touches it again, the ball slowly rolls to a stop. What force is directly responsible for stopping the ball?
Friction (between the ball and the grass)
Why do multicellular organisms like humans require complex transport systems (like the circulatory system), while unicellular organisms like amoebas do not?
Multicellular organisms have billions of specialized cells deep inside their bodies that cannot directly interact with the outside environment to exchange gases and nutrients.
An organism lives in a coastal North Carolina habitat where fresh water from a river mixes directly with salty water from the ocean. What specific aquatic ecosystem is this organism living in?
An estuary
During the day at North Carolina beaches, wind blows from the ocean toward the land. What is the name of this wind pattern, and why does it occur?
A sea breeze. It occurs because land heats up faster than water during the day, causing the warm air over land to rise and cool air from the sea to move in.
A 50-gram ice cube is placed in a sealed glass jar and left out in the sun. After it melts completely into liquid water, what will the mass of the water be? Explain your answer.
50 grams. According to the Law of Conservation of Mass, mass stays the same during a physical change.
A moving car suddenly slams on its brakes, and the passengers fly forward against their seatbelts. Which of Newton's laws explains why the passengers' bodies kept moving forward?
Newton's First Law (The Law of Inertia)
Which two human body systems must work directly together to allow you to lift a heavy box or run across a field?
The Skeletal System and the Muscular System
If all the primary consumers (herbivores) are suddenly removed from a localized food web, explain what will most likely happen to the population of the producers.
The producer population will increase because there are no herbivores eating them.
Over the winter, a heavy dip in the global Jet Stream drops far south below North Carolina. What change in local winter weather will this bring to the state?
It will bring unusually cold air down from the north.
Engineers leave tiny gaps or cracks between concrete sidewalk blocks and steel train tracks. What thermal phenomenon are they planning for?
Thermal expansion (objects expand when heated in the summer and contract when cooled in the winter).
A toy car travels a total distance of 60 meters in exactly 10 seconds. What was the average speed of the toy car? (Include units!)
6 meters per second (Speed = Distance / Time)
A child is an excellent basketball player, has a scar on their left knee, and has natural dimples when they smile. Which of these characteristics is an inherited trait?
The dimples. (Playing basketball is learned , the scar is acquired )
Fungi and bacteria are found growing on a fallen, rotting tree trunk in a deciduous forest. What critical role do these organisms perform to help the ecosystem survive?
They act as decomposers, breaking down dead material and returning nutrients back to the soil.
Why does the coastal region of North Carolina typically experience milder, warmer winters compared to the inland mountain regions at the same latitude?
The Gulf Stream moves warm ocean water north right along our coast, keeping coastal winters mild.
Give an everyday example of heat transfer via convection and explain how the molecules move during the process.
(Example: A pot of boiling water or warm air rising from a heater). Warm, less dense fluids/gases rise, while cooler, denser fluids/gases sink.
If you push a heavy wooden crate across the floor with 20 Newtons of force to the right, while a friend pushes the same crate with 20 Newtons of force to the left, what will happen to the motion of the crate?
The crate will not move because the forces are balanced.
Explain how the Digestive System and the Circulatory System interact with each other after you eat a meal.
The digestive system breaks down food into nutrients , and the circulatory system absorbs and transports those nutrients through the bloodstream to cells across the body.
Why are the trees in a temperate deciduous forest forced to lose their leaves every year, whereas the trees in a tropical rainforest keep theirs year-round?
Deciduous forest trees drop leaves to conserve water and survive freezing winter temperatures , while tropical rainforests stay warm and rainy year-round.
You notice heavy, dark clouds building rapidly upward in the sky on a hot summer afternoon, which are quickly followed by a severe thunderstorm. What specific type of cloud did you observe?
A cumulonimbus cloud
A student mixes a spoonful of sugar into warm water until it completely disappears and cannot be physically filtered out. Did the student create a mixture or a solution?
A solution (it is a combination of substances that cannot be easily separated).
Imagine a heavy bowling ball and a light tennis ball are dropped from the top of a building at the exact same time (ignoring air resistance). Which will hit the ground first, and why?
They will hit at the exact same time because gravity pulls on all objects equally regardless of mass.
Both a single-celled bacteria and a multicellular dog are living organisms. What are the 3 basic functions of life that both of these organisms must perform to survive?
1. Eat/take in nutrients, 2. Get rid of waste, 3. Reproduce