BIOLOGY 2

Eyepiece

Lens you look through.

Objective Lens

Main magnification lenses (rotate to change).

Stage

Platform for the slide.

Stage Clips

Holds slide in place.

Condenser

Focuses the light.

Iris Diaphragm

Adjusts light brightness/glare.

Illuminator

The light source.

Body Tube

Connects eyepiece to objectives.

Nosepiece

Rotates the objective lenses.

Arm

Backbone / carrying handle.

Coarse Adjustment Knob

Quick, rough focus (low power only).

Fine Adjustment Knob

Sharp, detailed focus (high power).

Base

Bottom support.

Epidermal hair (Trichome)

Reduces water loss and protects against insects.

Epidermis (Upper/Lower)

Outer skin; protects inner tissues.

Palisade cell

“Primary site of photosynthesis” (Tightly packed with chloroplasts).

Spongy cell

Air spaces for gas circulation, loosely packed cells with large air spaces (CO₂ and O₂).

Stoma

Pore for gas and water vapor exchange.

Guard cell

Opens and closes the stoma.

Bundle sheath

Protects and regulates the vascular vein.

Xylem

Transports water and minerals up.

Phloem

Transports food and sugars down/out.

Cuticle (Upper/Lower)

Waxy layer preventing water loss.

Micro molecules

Small organic molecules (monomers) that serve as the framework for macromolecules.

Glucose

A monosaccharide sugar that serves as the main fuel for cellular work.

Macromolecule

Large organic molecules (polymers) built from smaller micro molecules (monomers).

Examples of Macromolecules

Carbohydrates, lipids, proteins, and nucleic acids.

Carbohydrates

Macromolecules ranging from small sugar molecules to long starch molecules.

Monosaccharides

Simple single-unit sugars.

Ex. Fructose, glucose, and galactose.

Monosaccharide Examples

Fructose, glucose, and galactose.

Disaccharides

Sugar molecules made by joining two monosaccharides.
Ex. Fructose, Lactose, Maltose

Sucrose (Table Sugar)

Glucose + Fructose.

Lactose (Milk Sugar)

Glucose + Galactose.

Maltose (Grain Sugar)

Glucose + Glucose.

Polysaccharides

Complex carbohydrates composed of many linked monosaccharide chains.

Kinds of Polysaccharides

Starch, Glycogen, Cellulose

Starch

Plant polysaccharide used for energy storage (e.g., in potatoes and rice).

Glycogen

Animal polysaccharide used for sugar storage; found in skeletal muscles and the liver.

Cellulose

Structural plant polysaccharide found in cell walls and wood; acts as indigestible dietary fiber for humans.

Macromolecules: Lipids

Hydrophobic macromolecules that do not mix with water. Includes fats, waxes, steroids, and oils.

Lipid Functions

Stores energy, insulates the body, and cushions and protects organs.

Saturated Fatty Acids

Animal fats that are solid at room temperature, such as butter and shortening.

Unsaturated Fatty Acids

Plant oils that are liquid at room temperature and low in saturated fat.

Steroids

Lipids derived from a cholesterol base, used by the body to produce hormones.

Steroid Examples

Testosterone, estrogen, and progesterone.

Anabolic Steroids

Synthetic variants of testosterone used to build muscle mass quickly.

Macromolecule: Protein

Builds cells, acts as hormones and enzymes, and performs cellular work.

Amino Acids

The building blocks of proteins.

Adenosine Triphosphate (ATP)

A nucleotide base combined with three phosphate groups. Used by cells for energy.

ATP

Energy stored in chemical bonds in phosphate groups.

Adenosine Diphosphate (ADP)

Formed after ATP releases its stored energy and loses a phosphate group.

Basic Unit of Life

Cell - smallest unit of matter

Non-living Levels

Atoms, Molecules, Organelles

Living Levels

Cells
Tissues, Organs
Organ System Organism
Population (one species in an area)
Community (several populations in an area)
Ecosystem (forest, prairie...)
Biome (tundra, tropical rainforest...)
Biosphere (all living & nonliving things on Earth)

Viruses are non-living.

TRUE

Prokaryote

No Nucleus, One Cell, No Membrane-Bound

Eukaryote

True Nucleus, Uni/Multicellular, Membrane-Bound

Cell Membrane

Outer cover- phospholipid bilayer (phosphate heads and lipid tails).
Maintains cell's shape.
Control what enters or leaves the cell.

Cell Wall

Nonliving protective layer outside the cell membrane.
Cellulose in plants, peptidoglycan or phospholipids in bacteria, and chitin in fungi.

Cytoplasm

Gelatinous, colloidal fluid enclosed by the cell membrane contains protein-bound and non-protein-bound organelles.
Medium for cellular chemical.

Nucleus

Control center, contains DNA organized into chromosomes.

Nuclear Membrane

Double membrane around nucleus, contains pores to control transport and connected to rough ER.

Nucleoplasm

DNA found here, packed by histone (proteins) into chromosomes.

Nucleolus

Dark-staining body inside the nucleus. Synthesizes ribosomes to RNA molecules

Cytoskeleton

Network of microtubules, intermediate filaments, and microfilaments that maintains cell shape, supports internal organization, provides mechanical support, and enables cell division and movement.

Centrioles and Mitotic Spindle

Paired microtubule structures near the nucleus of animal cells that form the mitotic spindle and control chromosome movement during cell division.

Vacuoles

Fluid-filled storage sacs containing water, nutrients, wastes, enzymes, sugars, proteins, minerals, lipids, and salts. Large and central in plant cells, small or absent in animal cells, and absent in bacterial cells.

Mitosis

Cell division process in which chromosomes are replicated and separated to produce two genetically identical daughter cells.

Meiosis

Cell division process involving two successive divisions that produce four daughter cells with half the original genetic information.

Interphase

Longest stage. Cell grows, performs normal functions, and prepares for cell division.

G1 Phase (Gap 1)

Cell grows, carries out normal metabolic activities, and synthesizes proteins and organelles without DNA replication.

G0 Phase (Resting)

Cell is inactive and neither divides nor prepares for division.

S Phase (Synthesis)

DNA replication occurs, resulting in duplicated chromosomes.

G2 Phase (Gap 2)

Cell continues to grow and produces RNA, proteins, and other macromolecules needed for organelle multiplication and spindle formation.

Mitotic Phase (M Phase)

Nucleus and cytoplasm divide, producing two daughter cells.

Prophase I

Homologous chromosomes pair up (synapsis) and may exchange genetic material (crossing over).

Metaphase I

Homologous chromosome pairs align at the cell's equator.

Anaphase I

Homologous chromosomes separate and move to opposite poles; sister chromatids remain attached.

Telophase I & Cytokinesis

The cell divides, producing two haploid daughter cells.

Prophase II

Spindle fibers form in each of the two haploid daughter cells.

Metaphase II

Chromosomes align individually at the cell's equator.

Anaphase II

Sister chromatids separate and move to opposite poles.

Telophase II & Cytokinesis

Cells divide again, producing four genetically distinct haploid granddaughter cells.

MENDELIAN GENETICS

certain patterns of

how traits are passed from parents to offspring.

Law of Unit Factors in Pairs (Independent Assortment)

Random distribution of different gene alleles into gametes during meiosis, so inheritance of one trait does not affect another

Law of Dominance and Recessive

In the F1 generation, the dominant allele determines the expressed trait, while the recessive allele is not expressed.

Law of Segregation

Paired alleles separate randomly during gamete formation, so each gamete receives only one allele.

Cell Reproduction

Process of producing new cells of the same type. Includes two processes: mitosis and meiosis

Krebs Cycle (Citric Acid Cycle)

Occurs in the mitochondrial matrix

Part of cellular respiration

Runs in 2 cycles (turns) per glucose molecule.

Produces energy carriers used for ATP production (NADH, FADH₂)

Cell Theory

All living things are made of cells; cells come from pre-existing cells.

Robert Hooke

first discovered and named “cell” (cork cells)

Matthias Schleiden

plants are made of cells

🧑‍🔬 Theodor Schwann

– animals are made of cells

🧑‍🔬 Rudolf Virchow

– cells come from pre-existing cells

James Watson & Francis Crick

– DNA structure model

Antonie van Leeuwenhoek

– first to observe living microorganisms (“Father of Microbiology”)

Homologous

Same evolutionary origin, different functions.

Analogous

Different evolutionary origin, same function.