Adv. Biology Unit 2: Plant and Animal Systems Review

A complete set of vocabulary flashcards covering plant systems, animal systems, organ structures, and homeostatic regulation based on the lecture review sheet.

Phloem

Plant vascular tissue responsible for transporting organic nutrients, particularly sugars produced during photosynthesis in the leaves, to other parts of the plant.

Xylem

Plant vascular tissue that conducts water and dissolved mineral nutrients upward from the roots throughout the plant.

Guard Cells

Specialized epidermal cells surrounding each stoma that control its opening and closing in response to water pressure and environmental conditions.

Transpiration

The process by which water is absorbed by plant roots, moves up through the xylem, and evaporates through the stomata in the leaves.

Auxin

A plant hormone that stimulates cell elongation, causing plant stems to bend and grow toward light (phototropism).

Ethylene

A plant hormone in gaseous form that stimulates fruit ripening and induces plant tissue aging.

Abscisic Acid

A plant hormone that inhibits cell division and promotes seed dormancy to prevent growth under unfavorable conditions.

Tropism

A plant growth response toward or away from an environmental stimulus, such as phototropism (light), gravitropism/geotropism (gravity), thigmotropism (touch), or hydrotropism (water).

Capillary Action

The movement of water through narrow spaces within plant xylem driven by the combined forces of adhesion, cohesion, and surface tension.

Cohesion and Adhesion

Cohesion is the attraction between like water molecules, while adhesion is the attraction between water molecules and xylem cell walls; together they allow water to pull upward against gravity.

Angiosperms vs. Gymnosperms

Angiosperms produce flowers and enclose their seeds inside fruits, whereas gymnosperms produce seeds exposed on structures such as cones.

Primary Growth vs. Secondary Growth

Primary growth increases the length or height of plant stems and roots via apical meristems, whereas secondary growth increases stem and root thickness via lateral meristems.

Shoot System vs. Root System

The shoot system (stems, leaves, flowers) handles photosynthesis, transport, and reproduction above ground, while the root system anchors the plant and absorbs water and nutrients below ground.

Flower Anatomy Diagram

Diagram displaying flower reproductive structures: Sepal (A), Petal (B), Stamen (C: Anther E, Filament F), and Pistil/Carpel (D: Stigma G, Style H, Ovary I, Ovule J).

Monocot vs. Dicot Comparison Table

Table comparing Monocot and Dicot structural traits across seeds, leaves, flowers, stems, and roots.

Leaf Cross-Section Diagram

Diagram illustrating the anatomy of a leaf cross section: Cuticle/Upper epidermis (A), Palisade mesophyll (B), Spongy mesophyll (C), Lower epidermis (D), Stoma (E), Vascular bundle/vein (F), and Guard cells (G).

Endotherms vs. Ectotherms

Endotherms generate internal metabolic heat to maintain a constant body temperature, whereas ectotherms rely on external environmental heat sources to regulate body temperature.

Central Nervous System vs. Peripheral Nervous System

The Central Nervous System (CNS) consists of the brain and spinal cord to process information, while the Peripheral Nervous System (PNS) consists of all sensory and motor nerves connecting the CNS to the body.

Parasympathetic vs. Sympathetic Nervous System

The sympathetic nervous system activates fight-or-flight responses to danger, whereas the parasympathetic nervous system directs rest-and-digest functions during calm states.

Reflex Arc

The neural pathway of an involuntary reflex action, typically passing from receptor sensor through sensory neuron to spinal cord interneuron and motor neuron to effector muscle.

Open vs. Closed Circulatory System

In an open circulatory system, blood/hemolymph pumps into open body cavities bathing tissues directly, whereas in a closed circulatory system, blood remains entirely enclosed within blood vessels.

Epinephrine

A hormone secreted by the adrenal glands during dangerous or stressful situations to initiate the fight-or-flight response.

Homeostasis

The process by which biological systems maintain a stable internal environment despite fluctuations in external conditions.

Negative Feedback

A homeostatic mechanism that counteracts a change to bring a physiological variable back to its normal set point, such as insulin lowering blood glucose levels.

Positive Feedback

A homeostatic mechanism that amplifies a physiological change away from baseline until an end goal is reached, such as blood clotting or labor contractions.

Homeostatic Control Loop Diagram

Feedback loop model depicting: stimulus/imbalance (1), receptor/sensor (2), input signal (3), efferent output signal from control center (4), and effector response (5) restoring homeostasis.