Plant Cells and Growth

Vocabulary flashcards covering key terms from the lecture notes on plant cells and growth.

Shoot system

The aboveground organ system of a plant, including leaves, stems, and reproductive organs.

Root system

The underground organ system, usually consisting of roots.

Vegetative organs

Leaves and stems are the non-reproductive, growing parts of a plant.

Organ systems

Plant tissues form organs arranged into two main systems: shoot (aboveground) and root (underground).

Determinant growth

Growth with a genetically determined maximum size; growth stops after a time and often cannot regrow.

Indeterminate growth

Growth with no fixed maximum size; plants can keep growing and often heal/regenerate.

Cell theory

Idea that all living things are made of cells; cells are the basic unit of life; new cells arise from existing cells.

Omnis cellula e cellula

Latin for 'every cell comes from a cell'; cells arise by reproduction from pre-existing cells.

Plasma membrane

Phospholipid bilayer with embedded proteins; serves as a selective barrier between the cell and the environment.

Cytoplasm

Region between the plasma membrane and the nucleus, containing cytosol and cytoskeleton.

DNA

Molecule carrying genetic information; housed in the nucleus of eukaryotic cells.

Nucleolus

Region inside the nucleus where ribosomes are assembled.

Nuclear envelope

Double membrane surrounding the nucleus that separates it from the cytoplasm.

Chromatin

DNA bound to proteins; forms visible chromosomes during replication and growth.

Chromosomes

DNA-protein complexes that become visible during cellular replication; linear in eukaryotes.

Ribosomes

Sites of protein synthesis; not true organelles; can be free in cytoplasm or attached to the endoplasmic reticulum.

Endomembrane system

Network of membranes (ER, Golgi, vesicles, peroxisomes) that modifies, packages, and transports lipids and proteins.

Endoplasmic reticulum (ER)

Interconnected sacs and tubules that modify proteins and synthesize lipids.

Golgi apparatus

Flattened membrane-bound sacs that sort, tag, package, and distribute proteins and lipids from the ER.

Mitochondria

Powerhouse of the cell; site of cellular respiration; produces ATP; contains its own DNA and ribosomes.

Chloroplast

Plastid that stores chlorophyll and conducts photosynthesis; contains thylakoids and grana and has its own DNA and ribosomes.

Plastids

Plant cell organelles involved in storage and photosynthesis; includes chloroplasts, chromoplasts, amyloplasts.

Grana and thylakoids

Stacks of thylakoid membranes inside chloroplasts where light reactions of photosynthesis occur.

Central vacuole

Large, membrane-bound vesicle storing water and other materials; regulates turgor pressure.

Tonoplast

Membrane surrounding the central vacuole.

Cell wall

Rigid layer outside the plasma membrane; primary wall and secondary wall with middle lamella and cellulose microfibrils; lignin adds rigidity.

Middle lamella

Thin pectin layer that binds adjacent plant cells together.

Primary cell wall

Thin, elastic outer layer formed early; allows cell enlargement; composed of cellulose microfibrils.

Secondary cell wall

Thicker wall deposited inside the primary wall after maturation; lignified for rigidity.

Lignin

Complex polymer that strengthens secondary cell walls, especially in wood.

Cellulose microfibrils

Bundle-like cellulose fibers that determine the direction of cell expansion.

Plasmodesmata

Pores through cell walls that connect plant cells and enable transport and communication.

Apical meristem

Meristem at the tips of stems and roots; produces primary meristematic tissues.

Protoderm

Primary meristem that gives rise to the epidermis.

Ground meristem

Primary meristem that gives rise to ground tissue (photosynthetic, storage, support).

Procambium

Primary meristem that gives rise to vascular tissue (xylem and phloem).

Lateral meristem

Secondary meristem responsible for growth in girth; includes vascular cambium and cork cambium.

Vascular cambium

Lateral meristem that produces secondary vascular tissues (secondary xylem and phloem).

Cork cambium

Lateral meristem that produces periderm (secondary dermal tissue).

Intercalary meristem

Meristem located between nodes (common in grasses) enabling rapid regrowth.

Totipotent

Ability of plant tissues to regenerate into an entire plant.

Meristem

Region of active cell division and growth in plants.