Grade 7 Science Study Guide: Genetics to Cells

Genes and Inheritance

Traits are passed down from parents to offspring through genes.

Allele

Each parent contributes one allele for each gene.

Dominant Traits

Dominant traits appear even if only one allele is present.

Recessive Traits

Recessive traits only show up when both alleles are recessive.

Punnett Squares

Use Punnett squares to predict the possible genetic outcomes of a cross between two organisms.

Sex-linked Traits

Some traits are carried on the sex chromosomes (X and Y).

Genotype

Genotype has to do with what is going on inside of you.

Phenotype

Phenotype deals with your physical appearance.

Dominant Allele

A dominant allele is represented by a capitalized letter and determines whether a gene is dominant or recessive.

Natural Selection

The process where organisms with traits better suited to their environment are more likely to survive and reproduce.

Adaptations

Traits that help an organism survive in its environment.

Evolution

Over time, beneficial traits become more common in a population due to natural selection.

Biodiversity

The variety of life in an ecosystem; it's important for maintaining ecosystem balance.

Human Impact on Biodiversity

Activities like deforestation and pollution can harm biodiversity.

Conservation Efforts

Protecting species and habitats is essential to preserving biodiversity.

Cell Theory

All living organisms are made of cells; the cell is the basic unit of life.

Nucleus

Controls cell activities.

Mitochondria

Produce energy.

Chloroplasts

Conduct photosynthesis in plants.

Cell Membrane

Controls what moves in and out of the cell.

Ribosome

Where protein synthesis occurs.

Cytoplasm

Where the majority of the activities take place.

Cell Wall

Made of cellulose and strengthens the plant cell.

Vacuole

Space filled with cell sap which keeps the cell turgid.