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8th grade · Science · Unit 7 of 13

Genes & Heredity

Genes, mutations and reproduction.

What your child practices

Practices how genes on chromosomes code for proteins that shape traits, how mutations can be harmful, helpful or neutral, and how sexual and asexual reproduction differ in passing on genes.

Texas Essential Knowledge and Skills (TEKS) teks student expectation: 8.13(B) · genes on chromosomes determining inherited traits

How we explain it

Children can open this short lesson before they practice.

  1. Genes are pieces of DNA on chromosomes. They code for proteins that shape traits.
  2. A dominant allele shows its trait when present; a recessive one shows only if there are two.
  3. Mutations change DNA and can be harmful, helpful or neutral.

Example: B (brown) is dominant over b. Which color is an animal that is Bb? One dominant allele is enough to show. B is brown. Answer: brown

Genes & Heredity in Texas

In the Texas Essential Knowledge and Skills (TEKS), this is unit 7 of 13 in 8th grade Science, after Cells & Life Processes and before Natural Selection.

Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.

Source: Texas Education Agency (TEA)

Sample questions

A taste of this unit. In the app, questions change every time and get easier or harder to match your child.

  1. Question 1

    Genes carry instructions for making…

    • water
    • rocks
    • proteins
    • sunlight

  2. Question 2

    A mutation is…

    • a new cell wall
    • a change in DNA
    • a kind of rock
    • a type of food

  3. Question 3

    A recessive trait shows only when…

    • it is cold
    • the parent is older
    • one dominant allele is present
    • two recessive alleles are present

  4. Question 4

    Mutations can be…

    • always harmful
    • harmful, helpful or neutral
    • always helpful
    • never inherited

  5. Question 5

    Asexual reproduction produces offspring that are…

    • always sterile
    • very different from the parent
    • a mix of two parents
    • genetically identical to the parent

  6. Question 6

    In pea plants, purple (P) is dominant over white (p). A Pp plant has flowers that are…

    • striped
    • white
    • purple
    • pink

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