BIO STUDYGUIDE

Biology

The scientific study of life, encompassing everything from cells to large organisms.

Eight Characteristics of Life

Made of cells, reproduction, based on DNA, growth and development, use energy, respond to stimuli, maintain homeostasis, evolve over time.

Hierarchy of Life

An organized framework that categorizes life from smallest to largest: atom, molecule, organelle, cell, tissue, organ, organ system, organism.

Atom vs Cell

An atom is the smallest unit of matter, while a cell is the basic unit of life that can perform all life functions.

Observations

Gathering information using senses or tools; can be qualitative (descriptive) or quantitative (numerical).

Independent Variable

The variable that is manipulated or changed in an experiment.

Dependent Variable

The variable that is measured or observed in response to changes in the independent variable.

Control Group

A group in an experiment not exposed to the independent variable, used as a benchmark for comparison.

Constants

Factors in an experiment that are kept the same to ensure a fair test.

Qualitative Data

Descriptive data that can be observed but not measured.

Quantitative Data

Numerical data that can be measured and quantified.

Organic Compounds

Molecules containing carbon found in living things, such as sugars, proteins, fats, and DNA.

Carbohydrates

Organic compounds made of monosaccharides, serving as quick energy and structural components.

Proteins

Polymers made of amino acids that play roles in structure, metabolism, and function as enzymes.

Lipids

Organic compounds including fats and oils, functioning as long-term energy storage and components of membranes.

Nucleic Acids

Polymers made of nucleotides that store and transmit genetic information.

Prokaryotic Cells

Simpler, smaller cells without a nucleus, such as bacteria.

Eukaryotic Cells

More complex cells with a nucleus and organelles, found in plants and animals.

Plant Cells

Eukaryotic cells with cell walls, chloroplasts, and large vacuoles.

Animal Cells

Eukaryotic cells lacking cell walls and featuring small vacuoles.

Fungal Cells

Eukaryotic cells with cell walls made of chitin and no chloroplasts.

Nucleus

An organelle that stores DNA and regulates cell activities.

Rough Endoplasmic Reticulum

An organelle studded with ribosomes, responsible for protein synthesis.

Smooth Endoplasmic Reticulum

An organelle that synthesizes lipids and detoxifies substances.

Ribosomes

Cellular structures that synthesize proteins.

Golgi Apparatus

An organelle that modifies, sorts, and packages proteins for secretion.

Vesicles

Small membrane-bound sacs that transport materials within cells.

Mitochondria

Organelles that produce ATP energy through cellular respiration.

Chloroplasts

Organelles in plant cells that conduct photosynthesis.

Homeostasis

The ability of organisms to maintain stable internal conditions despite external changes.

Enzymes

Proteins that act as biological catalysts, speeding up chemical reactions.

ATP

A molecule that stores and transfers energy in cells.

Chemical Equation for Cellular Respiration

Glucose + Oxygen → Carbon dioxide + Water + ATP.

Purpose of Cellular Respiration

To convert chemical energy from glucose into usable ATP for cellular functions.

Aerobic

Processes that require oxygen to occur.

Anaerobic

Processes that occur without the presence of oxygen.

Fermentation

A metabolic process that occurs in the absence of oxygen, producing energy.

Lactic Acid Fermentation

A type of anaerobic respiration that occurs in muscle cells producing lactic acid.

Alcoholic Fermentation

A type of anaerobic respiration in yeast producing ethanol and carbon dioxide.

Photosynthesis

The process by which plants convert light energy into chemical energy stored in glucose.

Equation for Photosynthesis

CO₂ + H₂O + light → glucose + O₂.

Light Reactions

The first stage of photosynthesis, capturing sunlight to produce ATP and oxygen.

Calvin Cycle

The second stage of photosynthesis, using ATP to synthesize glucose.

Differentiation

The process by which cells become specialized for specific functions.

Mitosis

The process of cell division that produces two identical daughter cells.

Cytokinesis

The division of the cytoplasm resulting in two separate cells.

Purpose of Meiosis

To produce gametes with half the chromosome number and genetic diversity.

Homozygous

Having two identical alleles for a trait, e.g., AA or aa.

Heterozygous

Having two different alleles for a trait, e.g., Aa.

Dominant Allele

An allele that expresses its trait in a homozygous or heterozygous state.

Recessive Allele

An allele that only expresses its trait in a homozygous state.

Punnett Square

A diagram used to predict genetic outcomes of a cross.

Gene Pool

The total genetic diversity within a population.

Speciation

The evolutionary process by which new biological species arise.

Biodiversity

The variety of life in the world or in a particular habitat or ecosystem.