Science Practice Test – HowtoPasstheGED.com
The following practice test in Science is provided free of charge by HowtoPasstheGED.com.
Although this practice test is not official, HowtoPasstheGED.com aims to give realistic reinforcement for the material on the official GED test in Science.
This practice test consists of 38 questions.
Please take the test before checking the answers, along with links to the corresponding Science concepts, at Science Practice Test: HowtoPasstheGED.com – Answers.
As always, HowtoPasstheGED.com is meant to be a companion, not a substitute, for the official preparatory support provided by GED.com.
Butterfly Life Cycle
The butterfly life cycle consists of different life stages. The stages of the butterfly life cycle are as follows:
1 Egg (also known as Ovum)
All butterflies are oviparous (egg-producing). Depending on the species, butterflies can lay a few hundred to many thousands eggs. The shape of the eggs vary widely. The surface of the egg can be smooth or it can have pits and grooves. A female butterfly mostly lays her eggs on leaves or twigs. Depending on the temperature, the embryo develops in 1-3 weeks to a caterpillar. The color of the egg becomes darker as it matures.
2 Caterpillar (also known as Larva)
As soon as the embryo has developed into a caterpillar, it eats its way out of the egg. On the outside, the caterpillar mostly eats leaves and plants. While the caterpillars pass from the egg stage to the pupal stage, they typically shed their skin and molt several times.
3 Pupa (also known as Chrysalis)
During the caterpillar stage, butterflies can travel long distances in search of an ideal place to pupate. The insect undergoes lots of changes during this stage. Although it is outside, there is almost no physical activity. Depending on species and temperature, the pupal stage may last from a few weeks to several months.
4 Adult (also known as Imago)
The adult stage is the most known stage. The butterfly has its typical appearance: a hairy caterpillar-like body with jointed legs and usually relatively large wings. There are butterfly species that can survive winter and potentially live up to eight months. But most butterflies generally last only a few weeks.
1. Which of the following can you infer from this passage?
A. The butterfly life cycle is out of order.
B. The butterfly life cycle is out of control.
C. The butterfly life cycle is disorganized.
D. The butterfly life cycle goes to a lot of trouble to produce a short-lived adult.
2. What is the main idea of this passage?
A. The butterfly life cycle is spent mostly in flight.
B. The butterfly life cycle is egg-free.
C. The butterfly life cycle goes through a series of stages.
D. The butterfly life cycle is random.
3. According to the passage, all butterflies are:
4. According to the passage, Pupa is also known as:
5. Which of the following does this passage imply?
A. Bigger is better.
B. The caterpillar is a large metal machine.
C. Little can happen without a lot of movement.
D. A lot can happen with little movement.
Mosquito Life Cycle
The mosquito goes through separate and distinct stages of its life cycle. Each of these stages can be easily recognized by its special appearance as follows:
Eggs are laid one at a time or attached together to form “rafts.” They float on the surface of the water. In the case of Culex and Culiseta species, the eggs are stuck together in rafts of up to 200. Anopheles, Ochlerotatus, and Aedes, as well as many other genera, do not make egg rafts, but lay their eggs singly. Culex, Culiseta, and Anopheles lay their eggs on the water surface while many Aedes and Ochlerotatus lay their eggs on damp soil that will be flooded by water. Most eggs hatch into larvae within 48 hours; others might withstand subzero winters before hatching. Water is a necessary part of their habitat.
The larva (plural – larvae) lives in the water and comes to the surface to breathe. Larvae shed (molt) their skins four times, growing larger after each molt. Most larvae have siphon tubes for breathing and hang upside down from the water surface. Anopheles larvae do not have a siphon and lie parallel to the water surface to get a supply of oxygen through a breathing opening. Coquillettidia and Mansonia larvae attach to plants to obtain their air supply. The larvae feed on microorganisms and organic matter in the water. During the fourth molt the larva changes into a pupa.
The pupal stage is a resting, non-feeding stage of development, but pupae are mobile, responding to light changes and moving (tumbling) with a flip of their tails towards the bottom or protective areas. This is the time the mosquito changes into an adult. This process is similar to the metamorphosis seen in butterflies when the butterfly develops—while in the cocoon stage—from a caterpillar into an adult butterfly. In Culex species in the southern United States, this takes about two days in the summer. When development is complete, the pupal skin splits and the adult mosquito (imago) emerges.
The newly emerged adult rests on the surface of the water for a short time to allow itself to dry and all its body parts to harden. The wings have to spread out and dry properly before it can fly. Blood feeding (mosquito biting) and mating do not occur for a couple of days after the adults emerge.
6. Which of the following can you infer from this passage?
A. The mosquito life cycle depends on bronze.
B. The mosquito life cycle depends on silver.
C. The mosquito life cycle depends on gold.
D. The mosquito life cycle depends on water.
7. What is the main idea of this passage?
A. The mosquito life cycle does not vary among mosquito genera.
B. The mosquito life cycle is the same as meiosis.
C. The mosquito life cycle follows a series of distinct stages.
D. The mosquito life cycle is random.
8. According to the passage, in the case of Culex and Culiseta species, eggs are stuck together in:
9. According to the passage, the stage characterized by resting is:
10. Which of the following does this passage imply?
A. Mosquitoes are uniform.
B. Mosquitoes are molten.
C. Blood feeding is a large part of the mosquito life cycle.
D. Blood feeding is a small part of the mosquito life cycle.
Human Immunodeficiency Virus (HIV) can infect multiple cells in your body, including brain cells, but its main target is the CD4 lymphocyte, also called a T-cell or CD4 cell.
When a CD4 cell (blue cell in image above) is infected with HIV (yellow particles in image above), the virus goes through multiple steps to reproduce itself and create many more virus particles. The process is broken up into the following steps:
1 Binding and Fusion
This is the process by which HIV binds to a specific type of CD4 receptor and a co-receptor on the surface of the CD4 cell. This is similar to a key entering a lock. Once unlocked, HIV can fuse with the host cell (CD4 cell) and release its genetic material into the cell.
2 Reverse Transcription
A special enzyme called reverse transcriptase changes the genetic material of the virus, so it can be integrated into the host DNA.
The virus’ new genetic material enters the nucleus of the CD4 cell and uses an enzyme called integrase to integrate itself into your own genetic material, where it may “hide” and stay inactive for several years.
When the host cell becomes activated, the virus uses your own enzymes to create more of its genetic material, along with more specialized genetic material that allows it to make longer proteins.
A special enzyme called protease cuts the longer HIV proteins into individual proteins.
When these come together with the virus’ genetic material, a new virus has been assembled.
This is the final stage of the virus’ life cycle. In this stage, the virus pushes itself out of the host cell, taking with it part of the membrane of the cell. This outer part covers the virus and contains all of the structures necessary to bind to a new CD4 cell and receptors and begin the process again.
11. Which of the following can you infer from this passage?
A. The HIV life cycle depends on dead cells.
B. The HIV life cycle depends on resistant cells.
C. The HIV life cycle does not depend on accessible cells.
D. The HIV life cycle depends on accessible cells.
12. What is the main idea of this passage?
A. The HIV life cycle prefers brain cells.
B. The HIV life cycle targets unhealthy cells.
C. The HIV life cycle follows a series of self-reinforcing steps.
D. The HIV life cycle is random.
13. According to the passage, HIV’s main target is the:
A. brain cell
B. CD4 lymphocyte
14. According to the passage, the final stage of the HIV life cycle is:
15. Which of the following does this passage imply?
A. HIV infection is a simple process.
B. HIV infection is not methodical.
C. HIV infection is a death sentence.
D. Medications to control HIV infection should act to interrupt HIV’s life cycle.
Stuff Life Cycle
Everything we use goes through a life cycle, and each stage of the life cycle has environmental impacts, including climate change. However, reducing the use of materials in every stage of the life cycle minimizes the environmental impact associated with the stuff we use. The stages of the stuff life cycle are as follows:
1 Materials Extraction
All products are made from materials found in or on the earth. “Virgin” or “raw” materials, such as trees or ore, are harvested directly from the earth, then transported and processed. These activities use a large amount of energy, and burning fossil fuels to supply this energy results in greenhouse gas emissions. Recycling generally uses less energy than extracting and processing raw materials, so making new products from materials that have already been used (recycled materials) can save energy and reduce greenhouse gas emissions.
Products often require a great deal of energy to create, which results in greenhouse gas emissions. When a product is made with less material, or materials made with recycled content, less energy is needed to extract, transport, and process raw materials.
Finished products need to be transported to a distribution center or warehouse, then to stores and your home. In addition, each stage of the life cycle of a product requires some form of transportation. Transportation by plane, truck, or rail all require the use of fossil fuels for energy, which can contribute to global climate change.
Simply using a product may require energy, so it makes sense to purchase appliances that are energy efficient. Some appliances and electronics called “energy vampires” continually use power when plugged into an outlet, even when they are turned off. Some consumable products are formulated to reduce energy use, such as detergents that are formulated to work well in cold water. This reduces the demand for energy needed to heat water.
5 End-of-Life Management
End-of-Life management is what happens to our stuff after it has been used. How we manage our goods at the end of their current life can make a big difference in our environmental footprint. End-of-Life management techniques include reuse, recycling, composting, energy recovery, and landfill deposition.
16. Which of the following can you infer from this passage?
A. The stuff life cycle is invalid.
B. The stuff life cycle concerns only raw materials.
C. The stuff life cycle is frivolous.
D. The stuff life cycle would be less environmentally harmful with prudent management.
17. What is the main idea of this passage?
A. The stuff life cycle does not use fossil fuels.
B. The stuff life cycle does not result in greenhouse gas emissions.
C. The stuff life cycle goes through a series of stages.
D. The stuff life cycle is random.
18. According to the passage, raw materials are harvested directly from the:
19. According to the passage, the stage in which finished products are transported is called:
20. Which of the following does this passage imply?
A. Stuff happens.
B. Stuff is a matter of ashes to ashes, dust to dust.
C. Stuff lives and dies by the sword.
D. Stuff life cycle management is closely related to sustainability.
21. An animal cell includes a:
D. cell wall
22. A plant cell includes a:
A. bevy of vacuoles
C. malleable shape
23. In mitosis, chromosomes duplicate during:
24. In meiosis, homologous chromosomes line up next to each other and cross over during:
B. Meiosis 2
C. Meiosis 1
25. Which of the following characterizes both mitosis and meiosis?
D. cell division
C6H12O6 + 6 O2 —> 6 CO2 + 6 H2O + Energy
26. Based on the above biochemical reaction of cellular respiration, what is a waste product?
6 CO2 + 6 H2O + Energy —> C6H12O6 + 6 O2
27. Based on the above biochemical reaction of photosynthesis, what is a waste product?
28. In photosynthesis and cellular respiration, how many molecules of glucose are involved in each reaction?
29. Which of the following is a form of kinetic energy?
30. The base of an energy pyramid that is also a food chain typically consists of:
31. A block of wood has a mass of 108 g and a volume of 12 cm³. What is its density?
A. 96.0 g/cm³
B. 8.0 g/cm³
C. 9.0 g/cm³
D. 11.0 g/cm³
32. Based on the graph above, which salt’s solubility shows a changing rate of change?
°C = (°F – 32) ×
33. The temperature outside is 95 °F. What is the temperature in °C?
°F = °C × + 32
34. The temperature outside is 25 °C. What is the temperature in °F?
35. Over thousands of years, carbon dating tends to:
A. equalize age
B. underestimate age
C. overestimate age
D. nail age
F = ma
36. A car with a mass of 5000 kg accelerates at 2.5 m/s².
What force was applied to the car?
A. 2500 N
B. 12500 N
C. 5000 N
D. 7500 N
37. Based on the above map showing the theoretical continental drift of Earth’s land masses from hundreds of millions of years ago (Pangaea, Laurasia, Gondwanaland) to the present, which two continents used to be stuck together?
A. South America and Asia
B. South America and Africa
C. Europe and Asia
D. South America and Europe
38. The Big Bang Theory hypothesizes that the universe was once a very dense mass that began to:
D. turn into a TV show