What happens when a neuron’s membrane depolarizes? of 5 What happens when a neuron’s membrane depolarizes? :60 There is a net diffusion of Na out of the cell. There is a net diffusion of K into the cell. The neuron’s voltage inside becomes more positive. The neuron cannot send an action potential. The inside of the cell becomes more negative relative to the outside

A common feature of action potentials is that they: of 5 A common feature of action potentials is that they: :60 Cause the membrane to hyperpolarize and then depolarize. Can travel in more than one direction on an axon. Are triggered by a depolarization the reaches the threshold. Move at the same speed along all axons. Result from the diffusion of Na and K into the cell.

Where are neurotransmitter receptors located? of 5 Where are neurotransmitter receptors located? :60 On the nuclear membrane at the nodes of Ranvier On the postsynaptic neuron’s membrane On the membrane of the synaptic vesicles On the myelin sheath

of 5 Which of these correctly describes the distribution of ions in a resting neuron? :60 Na outside, K inside K outside, Na inside Proteins outside; K and Na inside Na & K outside; water inside only Ca outside and inside

The large intestine in humans: of 5 The large intestine in humans: :60 Digests all types of food. Is the longest part of the intestinal tract. Absorbs water. Is connected to the stomach. All of the above.

If I roll a: 1 – On your own, no notes 2 – On your own, with notes 3 – With partner, no notes 4 - with partner, with notes 5 – as a class, no notes 6 – as a class, with notes

From what you know about action potentials and synapses, propose three hypotheses for how various anesthetics might prevent pain.

The Skeletal System

Basic Functions of a Skeleton?

Types of Skeletons Exoskeleton Endoskeleton Sponges, echinoderms and invertebrates Internal Calcareous plates in Echinoderms Bone, cartilage or both in vertebrates Hydrostatic in other invertebrates Molluscs and arthropods External Plates of chitin or CaCO3

The Human Skeleton Living tissue Functions: Support Blood production Mineral storage Muscle attachment Protection

The Human Skeleton Starts as cartilage models OSTEOBLAST cells turn the cartilage to bone Begins in the middle of the bone by forming a PRIMARY OSSIFICATION CENTER Same thing begins to happen in the ends of the bones, forming SECONDARY OSSIFICATION CENTERS When the two centers meet, bone growth stops

The Human Skeleton Bone is remodeled throughout your lifetime OSTEOCLASTS break down bone and then OSTEOBLASTS rebuild in weak areas