Genetic Growth Factors - Middle School Life Science
- What is the term for a change in DNA sequence that can alter growth-related proteins?
- Mutation. DNA changes can create new protein variants affecting growth.
- Which inheritance pattern occurs when both alleles are fully expressed in the phenotype?
- Codominance. Both alleles contribute equally to the phenotype.
- What is the term for different versions of the same gene that can affect a trait such as height?
- Alleles. Different forms of a gene create variation in traits like height.
- What is the term for a DNA segment that contains instructions for making a specific protein?
- Gene. Genes are DNA segments that code for proteins, which control traits.
- Which option is a genetic factor influencing growth: nutrition level or allele differences?
- Allele differences. Genetic variation, unlike nutrition which is environmental.
- Identify the correct label: genotype or phenotype for the description "DNA alleles for height."
- Genotype. Alleles represent genetic makeup, not physical traits.
- What is the term for one allele masking the effect of another allele in a heterozygote?
- Dominance (dominant allele masks recessive). One allele's effect is visible while the other is hidden.
- What is the term for the allele combination an organism has for a trait that influences growth?
- Genotype. The genetic makeup determines which proteins are produced for growth.
- Which option best indicates a polygenic growth trait: blood type or human height?
- Human height. Height shows continuous variation from many genes.
- What is the term for a change in DNA sequence that can alter proteins and affect growth?
- Mutation. A permanent change in DNA sequence that can alter function.
- Which mutation type can shift the reading frame by adding or removing bases, often affecting growth proteins?
- Frameshift mutation (insertion or deletion). Adds or removes bases, disrupting the triplet reading pattern.
- Which type of mutation changes one DNA base and may change one amino acid in a protein?
- Point mutation (substitution). Replaces one nucleotide, potentially changing one amino acid.
- What is the term for turning genes on or off, changing growth without changing DNA sequence?
- Gene regulation (differential gene expression). Controls when and where genes are active without DNA changes.
- What is the term for a DNA segment that contains instructions for a specific trait affecting growth?
- Gene. A segment of DNA that codes for a specific protein or trait.
- Which term describes chemical tags on DNA or histones that can change gene activity and affect growth?
- Epigenetic modification. Reversible changes that affect gene expression, not sequence.
- Which term describes a trait like height that is influenced by many genes acting together?
- Polygenic trait. Multiple genes contribute to create continuous variation.
- Which genetic factor determines biological sex in many mammals and can influence average growth patterns?
- Sex chromosomes (XX or XY). Sex chromosomes carry genes that affect growth hormones.
- Which genetic factor explains why body size often shows a range rather than two categories?
- Polygenic inheritance. Many genes create continuous variation in traits like size.
- Which inheritance pattern produces an intermediate phenotype when heterozygous?
- Incomplete dominance. Heterozygote shows a blend between two homozygous phenotypes.
- What is the term for an organism's allele combination for a trait that can affect growth?
- Genotype. The genetic makeup showing which alleles an organism has.
- What is the term for a trait influenced by many genes, often producing a range of sizes or heights?
- Polygenic inheritance. Multiple genes combine effects to create continuous variation.
- What is the term for an organism's full set of DNA, including all genes that influence growth?
- Genome. The complete genetic material of an organism.
- What is the term for an allele that masks another allele's effect on a growth-related trait?
- Dominant allele. One copy is enough to express the trait fully.
- Identify the inheritance pattern: a trait shows a continuous range (many heights) due to many genes.
- Polygenic inheritance. Many genes create small additive effects for continuous traits.
- Which term describes a trait controlled mainly by one gene, often showing distinct categories?
- Single-gene (Mendelian) trait. Controlled by one gene pair following Mendel's laws.
- What is the term for the observable trait (such as body size) produced by genes and environment?
- Phenotype. Physical traits result from both genetic instructions and environmental factors.
- Identify the inheritance pattern: a trait appears only when genotype is aa, not Aa or AA.
- Recessive inheritance. Trait only appears with two recessive alleles.
- What is the term for an allele whose effect is masked unless two copies are present?
- Recessive allele. Must inherit two copies to express the trait.
- Identify the correct label: genotype or phenotype for the description "measured plant height."
- Phenotype. Observable traits are phenotypes, not genetic codes.
- What is the term for different versions of the same gene that can influence growth (for example, height)?
- Alleles. Alternative forms of a gene that create variation in traits.