9th Grade Accelerated Biology Flashcards

Flashcards for 9th Grade Honors Biology - Full Year Study Guide

Independent Variable

The variable you change in an experiment

Dependent Variable

The variable you measure in an experiment

Controlled Variables

Variables kept constant during an experiment

Control Group

A group used for comparison in an experiment

Constants

Stay the same in all groups; unchanging conditions

Prokaryotic

Cell type with no nucleus or membrane-bound organelles (e.g., bacteria)

Eukaryotic

Cell type with a nucleus and membrane-bound organelles (plants, animals)

Nucleus

Organelle for DNA storage and the control center of the cell

Mitochondria

Organelle that produces ATP (energy)

Ribosomes

Organelle responsible for protein synthesis

ER (Rough/Smooth)

Organelle for protein and lipid production

Golgi Apparatus

Organelle that packages and ships proteins

Lysosomes

Organelle responsible for digestion and waste removal

Chloroplasts

Organelle in plants for photosynthesis

Cell Wall

Provides structure and support in plant cells

Cell Membrane

Selectively permeable barrier of the cell

Selective Permeability

The membrane allows only certain molecules to pass—maintains homeostasis

Passive Transport

No energy required; molecules move from high to low concentration

Simple Diffusion

Small, nonpolar molecules (O2, CO2) move high to low concentration

Facilitated Diffusion

Uses proteins for large/polar molecules (glucose) to move from high to low concentration

Osmosis

Diffusion of water

Active Transport

Requires energy (ATP) to move substances from low to high concentration

Endocytosis

Cell engulfs large material

Exocytosis

Cell expels material

Hypertonic

Water exits; cell shrinks

Hypotonic

Water enters; cell swells

Isotonic

Equal movement of water in and out of the cell

Digestion

Break down food to absorb nutrients

Mouth

Mechanical & chemical digestion (saliva)

Esophagus

Peristalsis pushes food down

Stomach

Protein digestion begins (HCl + pepsin)

Small Intestine

Main site of nutrient absorption

Large Intestine

Absorbs water, forms feces

Liver

Produces bile (digests fats)

Pancreas

Produces digestive enzymes

Gallbladder

Stores bile

Amylase

Breaks down starch

Pepsin

Breaks down proteins

Lipase

Breaks down fats

Carbohydrates

Quick energy (Monomer: monosaccharides)

Proteins

Structure, enzymes (Monomer: amino acids)

Lipids

Long-term energy, insulation (Monomer: glycerol + fatty acids)

Nucleic Acids

Genetic material (DNA/RNA) (Monomer: nucleotides)

Enzymes

Biological catalysts (made of proteins)

Heart

Pumps blood

Arteries

Away from Heart

Veins

To Heart

Capillaries

Exchange gases

Respiratory System

Brings in oxygen, removes CO2

Digestive System

Breaks down food, absorbs nutrients

Nervous System

Coordinates body via electrical signals

CNS

Brain + spinal cord

PNS

All other nerves

Muscular System

Movement of body, organs

Skeletal System

Structure, protection, makes blood cells, stores minerals

Immune System

Defends against pathogens

Excretory System

Removes waste (e.g. urea via urine)

Endocrine System

Hormonal control (slow but long-lasting)

Reproductive System

Makes gametes (sperm/egg)

Genotype

Genetic makeup (e.g. Aa)

Phenotype

Physical trait

Homozygous

Same alleles (AA or aa)

Heterozygous

Different alleles (Aa)

Dominant/Recessive

One masks the other

Mitosis (Body Cells)

1 division → 2 identical cells

Meiosis (Gametes)

2 divisions → 4 different cells

DNA Sturcture

Double helix

Transcription

DNA → mRNA (via RNA polymerase)

Translation

mRNA → protein (uses tRNA and amino acids)

mRNA

Messenger

tRNA

Transfers amino acids

Cancer

Uncontrolled cell growth

Benign

Non-spreading

Malignant

Spreading

Carcinogens

Cancer-causing substances (e.g. UV, smoking)

Levels of Organization

Organism → Population → Community → Ecosystem → Biome → Biosphere

Energy Flow

Producers → Consumers → Decomposers

Mutualism

Both benefit

Commensalism

One benefits, one unaffected

Parasitism

One benefits, one harmed

Atom

Basic unit of matter

Element

Pure substance (H, O, C)

Molecule

Two or more atoms bonded

Compound

Different atoms bonded

Domains

Bacteria, Archaea, Eukarya

Classification

Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species

Binomial Nomenclature

Genus species (e.g. Homo sapiens)