General Biology 1: Cell Structure and Classification

This flashcard set covers the definitions, structures, and classifications of prokaryotic and eukaryotic cells, specifically focusing on plant, animal, bacterial, and archaeal cells as described in the lecture notes.

Cells

The basic building blocks of all living things, providing structure for the body and converting nutrients into energy.

Prokaryotes

Organisms like bacteria that serve as the foundation of many ecosystems and are involved in nutrient cycling and decomposition.

Eukaryotes

Building blocks of multicellular organisms characterized by a complex structure and compartmentalization, allowing for specialization.

Cell wall (Plant)

A rigid covering made primarily of cellulose that protects the cell, provides structural support, and gives shape.

Cellulose

A polysaccharide made of long, straight chains of $\beta$-glucose molecules connected by a 1–4 linkage; it is the major organic molecule in plant cell walls.

Peptidoglycan

The chief organic component of prokaryotic cell walls.

Chloroplasts

Organelles in photoautotrophic eukaryotic cells that possess their own DNA and ribosomes and are crucial for photosynthesis.

Autotrophs

Organisms, such as plants, that are able to make their own food, like glucose.

Heterotrophs

Organisms, such as animals, that must rely on other organisms for their organic compounds or food source.

Chlorophyll

The green pigment found in chloroplasts that captures sunlight for photosynthesis.

Central Vacuole

A large plant cell organelle that regulates water concentration, provides turgor pressure, and can deter herbivory with bitter fluid.

Lysosomes

Animal cell organelles known as "garbage disposals" that use digestive enzymes to break down proteins, lipids, nucleic acids, and worn-out organelles.

Suicide bags

A term for lysosomes because their enzymes can break down cellular components, including the cell itself, if the membrane ruptures.

Bacterium

A single-celled, prokaryotic organism without a true nucleus or membrane-bound organelles.

Plasmids

Small circular DNA pieces in bacteria that replicate independently and can grant properties like antibiotic resistance and pathogenicity.

Cocci

Bacteria that are spherical, round, or oval-shaped, such as the Staphylococcus group.

Bacilli

Bacteria that are rod-like or cylindrical shaped, such as the Bacillus group.

Spirilla

Bacteria that are spiral or coil-shaped, such as the Spirillum group.

Vibrios

Bacteria that are curved or comma-shaped, such as the Vibrio group.

Capsule

A complex polysaccharide layer covering bacterial cells that prevents dehydration and protects against larger microbes.

Gram-positive

Bacteria that stain blue or purple and have thick cell walls.

Gram-negative

Bacteria that stain pink or red and have thin cell walls.

Cytoplasmic membrane

A semi-permeable layer made of lipids and proteins that performs functions like energy generation, protein secretion, and nutrient transport.

Nucleoid

The region in bacteria where a single, circular DNA ranging from $160,000$ to $12,200,000$ base pairs is located.

Inclusion bodies

Non-living structures in the cytoplasm categorized into gas vacuoles, inorganic inclusions, and food reserves.

Flagella

Long, hair-like structures on bacterial cells that move in a propeller-like motion to aid in movement toward nutrients or light.

Pili

Short hair-like projections on bacteria used for attachment; specialized sex pili are used for reproduction.

Archaea

Prokaryotes similar in size to bacteria that thrive in extreme environments and have cell walls lacking peptidoglycan.