STAAR Success - High School Biology - Practice #1

• Mitochondria
• Free-floating DNA
• Nucleus
• Chloroplast

• Mutations in somatic cells for dark fur increased.
• Natural selection favored dark fur due to better camouflage.
• Mice with light fur selected darker environments.
• Migration of dark-furred mice into the area increased.

• Root and phloem
• Flower and xylem
• Root and xylem
• Stem and chloroplast

Group 2

Source 2.1

• Tentacles
• Mesoglea
• Zooxanthellae
• Nematocyst

Group 3

• Candida albicans and Saccharomyces cerevisiae
• Neurospora crassa and Candida albicans
• Saccharomyces cerevisiae and Neurospora crassa
• Candida albicans and cytochrome C

• The species share many anatomical similarities.
• The species have high molecular homology.
• The species are able to reproduce.
• The species are both fungi.

• Mitochondria
• DNA sequences
• Nucleotides
• Ribosomes

Group 5

Source 5.1

• Insertion
• Substitution
• Deletion
• Frameshift

• The protein will remain unchanged.
• The mutation may change a single amino acid in the protein.
• The mutation will delete an entire amino acid from the protein.
• The mutation will add an additional amino acid to the protein.

Group 6

• Increased availability of nitrogen in the soil
• Decreased nitrogen absorption, leading to slower growth
• Enhanced biodiversity of plants in the area
• Increased soil pH, allowing more nutrient absorption

• Adding nitrogen-fixing bacteria to the soil
• Increasing the use of synthetic fertilizers
• Replacing nitrogen-dependent crops with non-nitrogen-dependent crops
• Planting crops with shallow root systems

• They decrease the energy required to start the reaction by stabilizing reactants.
• They bind irreversibly to substrates, increasing reaction rates.
• They change the equilibrium of a reaction, favoring product formation.
• They increase the energy required for the reaction to occur.

• Solar energy → heterotrophs → autotrophs → decomposers
• Autotrophs → decomposers → solar energy → heterotrophs
• Solar energy → autotrophs → heterotrophs → decomposers
• Decomposers → autotrophs → heterotrophs → solar energy

• The mutation changes the shape of the DNA helix, blocking transcription entirely.
• The mutation introduces a premature stop codon, halting protein synthesis early.
• The mutation causes an amino acid substitution, altering the protein structure.
• The mutation changes the promoter region, reducing gene expression.

• Glycolysis
• Photosynthesis
• Fermentation
• Aerobic respiration