Year 11 Biology NSW Preliminary HSC - Vocabulary Flashcards

A comprehensive set of vocabulary-style flashcards covering key biology terms from the Year 11 NSW Preliminary HSC notes, including cell biology, biochemistry, plant physiology, anatomy and physiology, ecology, evolution, and geoscience concepts.

Eukaryote

A cell that contains a nucleus and membrane-bound organelles.

Prokaryote

A unicellular organism that lacks a nucleus and membrane-bound organelles.

Cytoplasm

A jelly-like fluid inside the cell in which the organelles are suspended.

Ribosomes

Site of protein synthesis.

Cell membrane

The semipermeable membrane surrounding the cytoplasm of a cell.

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

Cell wall

Rigid layer on the outside of cells that provides support and protection.

Nucleus

Control center of the cell containing genetic material.

Vacuole

A sac inside a cell that acts as a storage area.

Mitochondria

ATP producing organelle.

Chloroplast

An organelle found in plant and algae cells where photosynthesis occurs.

Endoplasmic Reticulum (ER)

The transportation system of the cell; it moves materials around the cell.

Golgi body

Receives proteins and other materials from the ER, packages them, and distributes them within the cell.

Lysosomes

An organelle containing digestive enzymes.

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

Osmosis

Diffusion of water through a selectively permeable membrane.

Fluid mosaic model

Model describing the arrangement and movement of the molecules that make up the cell membrane.

Phospholipid bilayer

Two layers of molecules that surround a cell.

Phospholipid

Individual bilayer molecule with a hydrophilic phosphate head and two hydrophobic lipid tails.

Carbohydrates in cells

Form glycolipids and glycoproteins when attached to lipids and proteins; digested by lysosomal enzymes.

Lipids in cells

Lipids form glycolipids used in cell detection and adhesion.

Integral proteins

Proteins that span the membrane; assist in movement of particles in and out of cells.

Peripheral proteins

Proteins associated with membrane surfaces; aid various membrane functions.

Transport proteins

Allow passage of hydrophilic substances across the membrane.

Carrier proteins

Bind to molecules and change shape to shuttle them across the membrane.

Cholesterol

Lipid that adds flexibility to the phospholipid bilayer.

Passive transport

Movement of substances across a cell membrane without energy.

Active transport

Movement of materials through a cell membrane using energy.

Hypertonic solution

Solute concentration greater than inside the cell; cell loses water.

Hypotonic solution

Solute concentration less than inside the cell; cell gains water.

Isotonic solution

Solution with the same concentration of water and solutes as inside the cell; no net water movement.

Exocytosis

Process by which the contents of a cell vacuole are released to the exterior by fusion with the cell membrane.

Endocytosis

Process by which a cell takes material into the cell by infolding of the cell membrane.

Phagocytosis

Phagocytic cells engulfing bacteria or other small cells.

Pinocytosis

Cells ingesting liquid through external vesicles.

Enzymes

Biological catalysts that speed up biochemical reactions without being consumed.

Substrate

Molecule that binds to the active site of an enzyme and undergoes a chemical reaction.

Activation energy

Energy needed for a chemical reaction; catalysis lowers this energy barrier.

Active site

Region of the enzyme where the substrate binds to speed up the chemical reaction.

Catabolic reaction

Breakdown reactions; often sped up by enzymes.

Lock and key

Model where the enzyme active site is rigid and matches the substrate like a key fits a lock.

Induced fit

Model where the active site molds to the shape of the substrate.

Enzyme denaturation

Permanent loss of enzyme structure and function due to factors like heat.

Competitive enzyme inhibition

Inhibitor molecule similar to substrate binds to the active site.

Non-competitive enzyme inhibition

Inhibitor binds to a site other than the active site, changing the active site shape.

SA:V (surface area to volume ratio)

A size-dependent factor that decreases as cells grow, limiting cell size.

Organic

Contains carbon and relates to living matter.

Inorganic

Not formed from living matter.

Photosynthesis

Conversion of light energy into chemical energy: 6CO2 + 6H2O → C6H12O6 + 6O2.

Cellular respiration

Process releasing energy by breaking down glucose with oxygen: C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP.

ATP

Adenosine triphosphate; main energy currency of the cell.

ADP

Adenosine diphosphate; remains when a phosphate is removed from ATP, releasing energy.

Anaerobic

Process that does not require oxygen.

Aerobic

Process that requires oxygen.

Glycolysis

First step of cellular respiration; glucose is split into two pyruvic acid molecules.

Excretion

Process by which metabolic wastes are eliminated from the body.

Urea

Major nitrogenous waste excreted in urine.

Unicellular organism

Organism made up of one cell.

Multicellular organism

Organism made up of many cells.

Eukaryotic cells

Contain a nucleus and membrane-bound organelles.

Prokaryotic cell

Lacks a membrane-enclosed nucleus and organelles; found in Bacteria and Archaea.

Prokaryotic examples

Archaebacteria, modern bacteria, cyanobacteria.

Eukaryotic examples

Animals, plants, fungi, protists.

Colonial organism

Collection of genetically identical cells living together in a connected group.

Specialised cells

Cells with unique structure to carry out a specific task.

Stem cells

Unspecialized cells that can differentiate into a variety of cell types.

Bone marrow

Where stem cells are mainly generated in mammals.

Meristematic tissue

Plant tissue at tips of roots/shoots responsible for growth.

Hierarchy of multicellular organisms

Organelles → cells → tissues → organs → organ systems → organism.

Epithelial tissue

Covers outside of the body and lines organs/cavities.

Connective tissue

Supports the body and connects its parts.

Collagen

Protein giving strength in connective tissue; elastin provides flexibility.

Nervous tissue

Carries electrical messages between the brain and body.

Muscle tissue

Tissue composed of muscle fibers that produce movement.

Dermal tissue

Protective outer plant layer (epidermis) formed by primary growth.

Vascular tissue

Xylem and phloem; conducts water and nutrients.

Ground tissue

All tissue between dermal and vascular tissues.

Autotroph

An organism that makes its own food.

Xylem

Vascular tissue that carries water upward from roots.

Phloem

Living vascular tissue that carries sugar and organic substances.

Root system functions

Anchorage, absorption, storage, transport.

Shoot system

Leaves; functions include photosynthesis, reproduction, storage, transport, hormones.

Mesophyll

Photosynthetic tissue between the upper and lower epidermis with air spaces.

Palisade cells

Closely packed photosynthetic cells in leaves.

Spongy cells

Loosely packed mesophyll cells in leaves.

Stomata

Small openings on the underside of a leaf for gas exchange.

Guard cells

Control stomatal opening/closing by turgidity.

Transpiration

Movement of water through a plant from roots to leaves.

Translocation

Phloem transport from sugar source to sink.

Pressure-flow hypothesis

Phloem transport driven by pressure differences created as water enters at sources.

Lenticels

Small openings in stems that allow gas and water exchange.

Homeostasis

Maintenance of a stable internal environment.

Respiration system

Organ system for gas exchange between blood, air, and tissues.

Alveoli

Tiny sacs in lungs for gas exchange.

Capillaries

Microscopic vessels for exchange between blood and body cells.

Trachea

Air passage to and from the lungs.

Lungs

Main respiratory organs; protected by rib cage; diaphragm aids breathing.

Bronchioles

Airways leading from the bronchi to the alveoli.

Diaphragm

Large muscle that aids breathing.

Gills

Organs exchanging gases with water.