Year 9 Science Term 3 Biological Sciences Vocabulary

100 vocabulary flashcards for Year 9 Science covering living systems organisation, nervous and endocrine regulation, immune responses, and scientific inquiry skills.

Cell

The basic structural and functional unit of all living organisms.

Tissue

A group of similar cells that perform a specific function.

Organ

A body part formed from different tissues working together to perform a particular job.

Organ System

A collection of organs that cooperate to carry out major body functions.

Sense Organ

Specialised organ (eye, ear, tongue, nose, skin) that detects changes in the environment.

Eye

Sense organ that detects light and enables vision.

Ear

Sense organ responsible for hearing and balance.

Tongue

Sense organ containing taste buds for detecting flavours.

Nose

Sense organ that detects airborne chemicals for smell.

Skin

Largest sense organ; detects touch, temperature, and pain.

Homeostasis

Maintenance of a stable internal environment in the body.

Imaging Technology

Tools like MRI, CT, and PET that allow non-invasive visualisation of internal body structures.

MRI (Magnetic Resonance Imaging)

Imaging method using magnetic fields and radio waves to create detailed body images.

CT Scan (Computed Tomography)

X-ray–based imaging technique that produces cross-sectional body pictures.

PET Scan (Positron Emission Tomography)

Imaging test that shows functional processes by tracking radioactive tracers.

Nervous System

Body system that coordinates responses through electrical signals.

Endocrine System

System of glands secreting hormones for long-term regulation.

Brain Stem

Lower brain region controlling vital involuntary functions like breathing and heartbeat.

Cerebellum

Brain region that coordinates balance, posture, and fine motor skills.

Cerebrum

Largest brain part responsible for thought, memory, and voluntary actions.

Hypothalamus

Brain region linking nervous and endocrine systems; regulates homeostasis.

Frontal Lobe

Cerebral lobe involved in reasoning, planning, and voluntary movement.

Parietal Lobe

Cerebral lobe processing touch, temperature, and spatial information.

Temporal Lobe

Cerebral lobe involved in hearing, language, and memory.

Occipital Lobe

Cerebral lobe that processes visual information.

Neuron

Nerve cell specialised for transmitting electrical impulses.

Sensory Neuron

Neuron that carries information from receptors to the CNS.

Motor Neuron

Neuron that carries commands from the CNS to effectors.

Interneuron

Neuron that connects sensory and motor neurons within the CNS.

Central Nervous System (CNS)

Brain and spinal cord; processes information and coordinates responses.

Peripheral Nervous System (PNS)

All nerves outside the CNS; relays messages to and from the CNS.

Reflex Arc

Fast, involuntary pathway bypassing the brain to produce quick responses.

Nerve Impulse

Electrical signal that travels along a neuron.

Neurotransmitter

Chemical messenger released at synapses to transmit signals between neurons.

Synapse

Junction between two neurons where neurotransmitters are released.

Myelin

Fatty insulating sheath that speeds up nerve impulse conduction.

Axon

Long neuron extension that carries impulses away from the cell body.

Dendrites

Branch-like extensions receiving signals from other neurons.

Cell Body

Main part of a neuron containing the nucleus and organelles.

Receptor

Structure that detects stimuli and initiates nerve impulses.

Effector

Muscle or gland that carries out a response to a nerve signal.

Poison

Substance that can disrupt biological processes and harm organisms.

Drug

Chemical that alters body function; may affect neurotransmitters.

Nicotine

Drug from tobacco that stimulates neurotransmitter release, increasing heart rate.

Botulinum Toxin

Poison produced by bacteria that blocks neurotransmitter release, causing paralysis.

Pituitary Gland

‘Master’ endocrine gland controlling other glands via hormone release.

Adrenal Gland

Endocrine gland above kidneys; secretes adrenaline and cortisol.

Thyroid Gland

Neck gland regulating metabolism via thyroxine.

Pancreas

Gland producing insulin and glucagon to regulate blood glucose.

Ovaries

Female reproductive glands producing eggs and hormones oestrogen and progesterone.

Testes

Male reproductive glands producing sperm and testosterone.

Hormone

Chemical messenger transported in blood to target organs.

Negative Feedback

Control mechanism that reverses a change to maintain homeostasis.

Blood Glucose Regulation

Homeostatic control of sugar levels by insulin and glucagon.

Insulin

Hormone lowering blood glucose by promoting cellular uptake.

Glucagon

Hormone raising blood glucose by stimulating glycogen breakdown.

Thermoregulation

Homeostatic maintenance of stable internal body temperature.

Diabetes

Disease where blood glucose regulation fails due to insulin issues.

Pathogen

Micro-organism capable of causing disease.

Infectious Disease

Illness caused by pathogens and transmissible between hosts.

Non-Infectious Disease

Disease not caused by pathogens, e.g., genetic or lifestyle related.

Immune System

Body’s defence network against pathogens.

First Line of Defence

Physical and chemical barriers preventing pathogen entry (skin, mucus, etc.).

Second Line of Defence

Non-specific internal responses like inflammation and phagocytosis.

Third Line of Defence

Specific immune response involving lymphocytes and antibodies.

Antigen

Foreign molecule that triggers an immune response.

Antibody

Protein produced by B cells that binds specific antigens.

Immunity

Ability to resist a particular disease, often after exposure or vaccination.

Vaccine

Preparation of weakened or inactive pathogens used to stimulate immunity.

Vaccination

Administration of a vaccine to produce immunity.

Immunisation

Process of becoming protected against disease through vaccination.

Innate Immunity

Non-specific defence present from birth (first and second lines).

Adaptive Immunity

Specific, learned response involving T and B lymphocytes.

Inflammation

Localised response causing heat, redness, swelling, and pain.

Phagocytosis

Process where white blood cells engulf and digest pathogens.

Lymphocyte

White blood cell involved in adaptive immunity (B and T cells).

B Cell

Lymphocyte that produces antibodies against antigens.

T Cell

Lymphocyte that attacks infected cells or regulates immune responses.

Memory Cell

Long-lived lymphocyte enabling faster response on re-exposure to antigen.

Epidemiology

Study of disease distribution and determinants in populations.

COVID-19 Vaccine

Immunisation developed to protect against SARS-CoV-2 infection.

Cervical Cancer Vaccine

HPV vaccine developed to prevent cervical cancer (Gardasil).

Ian Frazer

Immunologist who co-developed the HPV cervical cancer vaccine.

Scientific Inquiry

Systematic investigation using evidence to answer questions.

Hazard

Potential source of harm in a scientific investigation.

Dissecting Equipment

Tools like scalpels and forceps used to examine biological specimens.

Graph Interpolation

Estimating values within the range of measured data points.

Graph Extrapolation

Predicting values beyond the measured data range.

Data Analysis

Process of examining data to identify patterns or relationships.

Controlled Variable

Factor kept constant during an experiment.

Independent Variable

Factor deliberately changed by the experimenter.

Dependent Variable

Factor measured in response to changes in the independent variable.

Reliability

Consistency of measurement results when repeated.

Accuracy

Closeness of a measured value to the true value.

Precision

Degree to which repeated measurements give similar results.

Hypothesis

Testable prediction explaining an observation or phenomenon.

Experimental Conclusion

Summary statement that interprets results in relation to the hypothesis.

Peer Review

Evaluation of scientific work by experts before publication.

Scientific Communication

Sharing research findings through reports, presentations, or publications.

Reflex

Rapid, automatic response to a stimulus (e.g., pupil constriction in bright light).