IB Biology: Option A (Neurobiology) with Complete Solutions

IB Biology: Option A (Neurobiology) with Complete Solutions Neural tube - develops by neurulation - elongates as embryo grows - develops in first month of gestation (humans) Neurulation development of a dorsal nerve cord at an early stage in development in chordates Neural pruning removal of dendrites and axon branches from some neurons Medulla oblongata controls autonomic activities e.g. swallowing, digestions, vomiting, breathing, heart rate Cerebellum coordinates unconscious functions e.g. posture, non-voluntary movement, balance Hypothalamus maintains homeostasis via coordination of nervous and endocrine systems, synthesizes hormones secreted by pituitary gland Pituitary gland Posterior stores and releases hormones produced by hypothalamus. Anterior produces and releases hormones that regulate many body functions Cerebral hemispheres Integration center for highly complex functions (higher order functions) e.g. learning, memory, emotion Sympathetic nervous system prepares body for "fight or flight" Parasympathetic nervous system involved in processes when body is relaxed Autonomic nervous system Sympathetic NS + Parasympathetic NS Photoreceptors in the eye Rod and cone cells Lens changes focal distance of eye by changing shape Aqueous humor provides nutrition to cornea and lens Pupil regulates amount of light that enters the eye Iris regulates light levels that enter eye Cornea protects the eye Vitreous humor fills space between lens and retina. keeps shape of eye Sclera tough protective layer around eye Choroid absorbs light in the eye