SOLUTIONS Yr 9 Revision Booklet.docx

Nervous System

Coordinates and controls body functions through electrical and chemical signals.

Central Nervous System

Analyzes information and makes decisions, located in the brain and spinal cord.

Peripheral Nervous System

Divided into somatic (voluntary) and autonomic (involuntary) systems.

Neuron

Consists of dendrite, axon, myelin sheath, cell body, axon terminals, and synapses for nerve impulse transmission.

Reflex Arc

Involuntary and rapid response to stimuli, involving sensory, relay, and motor neurons.

Stimulus

Anything that triggers a response, like touch, sound, taste, sight, or smell.

Sensory Receptor

Detects stimuli and sends signals to the nervous system.

Motor Neuron

Transmits messages from the CNS to effectors like muscles or glands.

Brain and Spinal Cord

Components of the central nervous system controlling body functions.

Electrical Impulse

Rapid transmission of signals within neurons.

Chemical Signal

Neurotransmitters released between neurons for communication.

Sensory, Interneuron, Motor Neurons

Components of the reflex arc for rapid responses.

Reflex Action

Involuntary reaction controlled by the spinal cord for quick responses.

Endocrine System

Regulates body functions through hormone secretion.

Hormone

Chemical messengers released by glands to control body functions.

Homeostasis

Maintaining internal balance in the body.

Negative Feedback Loop

Mechanism to maintain homeostasis by reversing changes.

Thermoregulation

Process of regulating body temperature through sweating or shivering.

Internal Fertilization

Fertilization occurs inside the body.

External Fertilization

Fertilization occurs outside the body.

Genetic variation

Variation in the DNA sequence among individuals of a species

Advantages of asexual reproduction

Only one parent needed, rapid population increase, time and energy efficient

Disadvantages of asexual reproduction

Limited number of offspring, longer gestation time, need to find a mate, not energy efficient, lack of genetic variation

Examples of organisms

Mammals, bacteria, some plants

Internal fertilization

Fertilization occurs inside the female body, limited offspring, increased survival chance, long gestation, parental care, selective mate

External fertilization

Fertilization occurs outside the female body, large offspring numbers, decreased survival chance, limited parental care, shorter gestation, not selective mate

Luteinizing hormone (LH) function

Promotes ovulation (release of the egg)

Progesterone function

Maintains the lining of the uterus

Menstrual cycle stages

Menstruation, Follicular stage, Ovulation, Luteal phase

Stroop experiment

Test of automatic and controlled processes, participants timed to say the color of words, automatic processes faster than controlled processes