8th Grade Science CBA Review Fall

A Photograph of a litter of Six Week Old bulldog puppies shows that the puppies are not identical. Even though these puppies have the same parents, they do not all look alike because---

• they are produced by asexual cloning

• some of the puppies have genetic material from only one of the parents

• each puppy has a different combination of genetic material as a result of sexual reproduction

• all the puppies developed from the same fertilized egg.

Tags

NGSS.MS-LS3-2

Sodium (Na) and Lithium (Li) have similar chemical properties. What characteristic of these elements explain why they are chemically similar

• Their atoms both have one valence electron.

• Their atoms both have more neutrons than protons.

• Their atoms have the same number of energy levels

• Their atoms contain equal number of protons and electrons.

Answer explanation

Remember that chemical properties are determined by an atoms VALENCE ELECTRONS.

A student was given this partial dichotomous key and asked to determine in which of the five orders the adult insect shown belongs. Based on the dichotomous key, in which order does the insect belong?

• Diptera

• Isoptera

• Ephemeroptera

• Zoraptera

The diagram shows a model of an atom. The model contains three different subatomic particles. Particles X and Y are inside the nucleus, and particle Z is outside of the nucleus. Which statements best describe the charges on the particles in this model?

• Both particles X and Y have a positive charge. Particle Z has a negative charge.

• Both particles X and Y have a negative charges. Particle Z has a positive charge.

• Either particle X or particle Y has a positive charge. Particle Z has a negative charge.

• Either particle X and Y has a negative charge. Particle Z has a positive charge.

Tags

NGSS.MS-PS1-1

Farmers can best reduce negative effects on the water quality of nearby streams and lakes by planting crops that

• produce less oxygen

• produce less carbon dioxide

• need less fertilizer

• need less solar energy

Tags

NGSS.MS-ESS2-4

NGSS.MS-LS2-5

Buffelgrass is an invasive species of grass from Africa that outcompetes native Texas grasses for space and water. Which long-term change to a Texas grassland would most likely occur due to the introduction of buffelgrass?

• The population of native grasses will increase.

• The population of native grasses will decrease.

• Buffelgrass offspring will develop traits like those of native grasses.

• Buffelgrass offspring will develop traits like those of other invasive species.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Students collected data on five elements. Their data is shown in the table. Which element has the same number of energy levels as lithium?

• Beryllium (Be)

• Sodium (Na)

• Magnesium (Mg)

• Potassium (K)

Oxygen and oxygen-containing compounds are involved in many different reactions. Which balanced equation represents a reaction that involves 14 atoms of oxygen?

Tags

NGSS.MS-PS1-5

Two plant species that grow in the same area are shown. Which statement best explains a difference between Plant 1 and Plant 2?

• Plant 1 obtains more water from the soil because of its root surface area and root depth.

• Plant 1 obtains more sunlight because of its root surface area and root depth.

• Plant 2 obtains more water from the soil because of its root surface area and root depth.

• Plant 2 obtains more sunlight because of its root surface area and root depth.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS1-5

A Texas Gulf Coast energy pyramid is shown with representative organisms at each trophic level. Which statement best describes the flow of energy through this pyramid?

• The trophic level represented by catfish and gobies receives energy directly from the producers.

• The trophic level represented by shrimp and copepods receives energy directly from the tertiary consumers.

• The trophic level represented by redfish and flounder receives energy directly from the secondary consumers.

• The trophic level represented by wire grass and phytoplankton receives energy directly from the primary consumers.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3