Quiz 1

Pros • Longer life span • Cells specialize and are more efficient • Bigger is better ( injuries can be sustained, harder to prey upon) • Sexual reproduction: increased genetic diversity (better situated to respond to environment/diseases/etc.)

Cons • Increased energy requirements • Can no longer rely on osmosis and simple diffusion alone • Longer time to reach adulthood /sexual maturity to reproduce (have to live to sexual maturity to get offspring) • Infections

• Get all resources from environment • Expel waste similarily • Heat up/cool down quickly bc small (fever kills unicellular) • Size must be small for diffusion to meet needs • Not a lot of storage space for energy (needs to be active or dies) • The range of environments available are small • Reproduce quicly and a lot (and die quickly and a lot)

• Diffusion • Bulk transport (circulatory system) Overcome limitations of diffusion • maximizing SA (SA:V ratio) and concentration gradients • utilizing bulk flow

Connective Epithelial Muscular Nervous Stomach has all types

Fat, bone, cartilage, and more

Covers our bodies surfaces Epithelium: Above Endothelium: Below

Skeletal Smooth (no regulation of this. unconscious) Cardiac tissue

Specialized cells that conduct signals

Communicating necessary info to all cells • Nervous system (quick signal) • Endocrine syste (long lasting signal. hormones) Translating signals into actions • muscles • skeleton Distribution of nutrients, energy, and oxygen to muscles • respiration (breathing) get to muscles • GI tract (energy/nutrition helps break down/process E) • Circulatory system Removal of waste created by breakdown of E • GI tract • Kidneys Defense • Immune system: small bad things • Brain: larger bad things SOLUTION: HOMEOSTASIS

Maximizing surface area and concentration gradients and utilizing bulk flow.

Homeostasis allows for changes to occur but in an acceptable and narrow range. It continuously monitors and regulates to keep a stable internal environment.

ANS Stimulus: From environment (ex: cold) Sensor: Body part (ex: hypothalamus). Decides what’s important. Has sensory neurons Effector: What your body does to fix problem (ex: muscles shiver) Response: How your body changes (heats up)

A stimulus is sensed by the sensor. The sensor signals to the effector. The effector changes something which leads to a response. Because the response fixes the problem caused by the stimulus, the response shuts down the sensor and the pathway.

Bunch of neurons in one spot

More complex neurons have nerve cords and the most complex have sensory organs

Formed by bundles of neurons Recieve, process, and transmit information

Concentrating sensory organs and nervous system components at the head of the body. Allows us to move and take in information at the same time. Convergent evolution: evolved independently several times • Forward locomotion • Predatory adaptation Evolutionary arms race between predators and prey

Sensory neurons: cell body on axon Interneuron (in spinal cord or brain): cell body on dentrites Motor neurons: cell body in dentrites

Decision maker Decides what’s improtant/enough info to reach the threshold potential

Chemicals Acetylcholine

EPSP –> Fire axon potential • Stimuli are received by dendrites and cell body • Synaptic stimuli are summed at the axon hillock, where an action potential is triggered if the sum of the signal reaches the threshold potential • Action potentials are conducted along the axon to the axon terminal where they cause the release of neurotransmitters. • Neurotransmitters bind to receptors on the postsyaptic cell membrane, potentially creating a new signal in the postsynaptic neuron.

-70mV (more - on inside, most + on outside because More Na+ outside less K+ inside. Anionic proteins are in higher concentration in the cell) Inside: Higher concentration of K+ and organic Anions Outside: Higher concentration of Na+, Ca2+, Cl- Pumps are V’s Leak channels have O’s

More of these than Na leak channels Always open