Understanding the Central Nervous System and Endocrine System in GCSE Biology
The central nervous system and endocrine system work together to maintain homeostasis and regulate bodily functions, making them crucial topics in AQA Combined Science Biology Paper 2. The central nervous system CNS consists of the brain and spinal cord, which process information through electrical signals transmitted via neurons. These signals travel rapidly through synapses, allowing for quick responses to environmental changes and threats.
Definition: The central nervous system CNS is the control center of the body, comprising the brain and spinal cord, which coordinate all bodily functions and responses through electrical signaling.
The endocrine system operates through chemical messengers called hormones, which are released by various glands throughout the body. Key hormones include insulin from the pancreas for blood glucose regulation, thyroxine from the thyroid for metabolism control, and adrenaline from adrenal glands for the fight-or-flight response. This system provides slower but longer-lasting responses compared to the nervous system, making it essential for maintaining long-term bodily functions.
Highlight: Understanding hormone action is crucial for inheritance, variation and evolution GCSE Biology AQA as it relates to reproductive development and genetic expression.
The reproductive system relies heavily on hormonal control, particularly through the pituitary gland's release of FSH FollicleStimulatingHormone and LH LuteinizingHormone. In females, these hormones regulate the production of oestrogen from the ovaries, controlling the menstrual cycle and egg maturation. In males, they stimulate testosterone production in the testes, essential for male reproductive development.