Bio 111 Exam 3 Flashcards
Nervous System
-transfers information about external environment
-all animals have some type of nervous system
-comprised of brain, spinal cord, and nerves
-simple animals have nerves only
Hydra Nervous System
nerve net
Seastar Nervous System
-radial nerve
-nerve ring
Insect Nervous System
-brain
-ventral nerve cord
-segmental ganglia
Ganglia
-segmentally arranged clusters of nerves in insects
-connected to brain
Chiton Nervous System
-ganglia
-anterior nerve ring
-longitudinal nerve cords
Squid Nervous System
-brain
-ganglia
Salamander Nervous System
-brain
-spinal cord
-sensory ganglia
Human Nervous System
-brain
-spinal cord
-nerves
Central Nervous System
-brain and spinal cord
-integration
Peripheral Nervous System
-nerves
-connects central nervous system to rest of body
-carries out actions directed by brain/spinal cord
Somatic Nervous System
-nerves that carry instructions from brain to skeletal muscles
-voluntary
Autonomic Nervous System
-nerves that regulate internal environment
-control smooth and cardiac muscles
-involuntary
Sympathetic Division
-corresponds to arousal and energy generation
-fight or flight
-faster heartbeat
-liver converts glycogen to glucose
-secretion of adrenaline
Parasympathetic Division
-promotes calming and return to self
-rest and digest
-lowers heart rate
-increase glycogen production
Enteric Division
-network of neurons in digestive tract, pancreas, and gall bladder
-controls peristalsis
-controls secretion
Three Functions of Nervous System
-sensory input
-integration
-motor output
Sensory Input
-sense
-five senses
Integration
-process
-analyze
-make decisions
-brain/spinal cord
Motor Response
-response to stimulus
-communicate to effector like muscle
Neurons
-functional unit of nervous system
-bundled together to form nerves
-conduct messages
Schwann Cells
-supporting cells
-provide structure
-insulate
-protect neurons
-produce myeline (a protein)
Neuron Structure
-nucleus
-dendrites
-axon
-axon hillock
Dendrites
-highly branched extensions
-receive signals from other cells
Axon
-long extension
-transmits signals at synapses
Three Types of Neurons
-sensory neurons
-interneurons
-motor neurons
Sensory Neurons
-communicate to brain about external environment
-eyes, ears, nose, skin, tongue
-long axon
Interneurons
-integrate information
-analyze sensory input
-remember and relate from the past
-highly branches axons and dendrites
Motor Neurons
-communicate response to muscle or effector cells
-long dendrites
Schwann Cells
-Glial Cells
-essential for structure of neurons
-form myelin sheaths around axons of neurons
Myelin Sheath
-layers which provide insultation of axon
-occurs in segments
-open area of segments called node of Ranvier
Information Flow Through Neurons
-dendrites receive information
-cell body processes information
-axon transmits signals to other cells at synapses
Synapses
-a junction between an axon and another neuron or effector
-leads to release of chemical messengers (neurotransmitters)
Reflexes
-sensory information bypasses the brain
-spinal cord makes decision
-rapid response
Neurons
-send messaged electrochemically
-charged ions cause electrical signal
Important Ions of Nervous System
-Sodium (Na+)
-Potassium (K+)
Membrane Potential
-voltage across neuron membrane
-changes act as signals
-changes occur from -70mV to +40mV
Resting Potential
-membrane potential of neuron not sending signals
-equal to -70mV
-concentration of potassium highest inside cell
-concentration of sodium highest outside cell
Ion Pumps
-establish resting potential of neuron
Ion Channels
-work through diffusion
-movement from high to low
Action Potential
-occurs when neuron is fired or receives information
-changes membrane potential from -70mV to +40mV
-rising phase
-falling phase
-undershoot
-occurs at node of Ranvier
Rising Phase
-depolarization
-sodium channels open and sodium flow into cell
-changes membrane potential from -70mV to +40mV
Falling Phase
-repolarization
-sodium channels close
-potassium channels open and potassium flows out of the cell
-membrane potential returns to -70mV
Undershoot
-resting potential is restored
-active transport brings sodium out of cell
-active transport beings potassium into cell
Neurotransmitter
-stored in synaptic terminal at end of axon
-are recycled
Types of neurotransmitters
-Substance P
-endorphins
-serotonin
-dopamine
-melatonin
-epinephrine
-norepinephrine
-GABA
-Glutamate
Hormones
-chemicals secreted into blood
-communicate messages through body
-only target cells with specific receptors for the hormone
Metamorphosis
-complete change in body form
-regulated by hormones
-involves juvenile hormone
-cause different parts of insect body to develop at different times
Functions of Hormones
-maintain homeostasis
-reproduction
-growth and development
-production of energy
Endocrine Glands
-pineal gland
-hypothalamus
-pituitary gland
-thyroid gland
-parathyroid glands
-adrenal glands
-pancreas
-ovaries
-testes
Hypothalamus
-in brain
-secretes ADH and oxytocin
ADH
-produced in hypothalamus
-stored in posterior pituitary gland
-targets kidneys
-effects water balance
Oxytocin
-produced in hypothalamus
-stored in posterior pituitary gland
-targets uterine muscles
-causes contraction during labor
Posterior Pituitary Gland
-stores hormones secreted in hypothalamus
Anterior Pituitary Gland
-produces six hormones
-ACTH
-FSH
-LH
-GH
-PRL
-TSH
ACTH
-produced in anterior pituitary gland
-targets adrenal gland
-causes production of glucocorticoids
-causes production of stress hormones
FSH
-Follicle stimulating hormone
-produced in anterior pituitary gland
-targets ovaries
-production of sex hormones
-start of menstruation
LH
-luteinizing hormone
-produced in anterior pituitary gland
-targets testes
-production of sex hormones
GH
-growth hormone
-produced in anterior pituitary gland
-targets bones
-causes growth
PRL
-prolactin
-produced in anterior pituitary gland
-targets mammary glands
-causes mammary gland growth
-causes production of milk
TSH
-thyroid stimulating hormone
-produced in anterior pituitary gland
-targets thyroid
-causes formation of thyroid hormones t3 and t4
-effects metabolism
Pineal Gland
-located in brain
-produces MSH
MSH
-melanocyte stimulating hormone
-produced by pineal gland
-regulates skin color
-controls pigment distribution in melanocytes
Three Types of Hormones
-proteins
-amino acids
-sterioids
Protein hormones
-not hydrophobic
-bind to receptors on surface of target cell
-can’t enter plasma membrane
Amino Acid Hormones
-not hydrophobic
-bind to receptors on surface of target cell
Steroid hormones
-hydrophobic
-enter the target cell
-bind to receptor in cell
-hormone-receptor complex enters nucleus and turns on genes to produce protein by gene expression
Three Stages of Protein Hormone Action
-Reception
-Signal Transduction
-Response
Reception (protein)
-hormone binds to a receptor on membrane of target cell
Signal Transduction (protein)
-binding of hormone to receptor
-activation of enzymes in cell
-signal sent to secondary messenger (cAMP)
-cAMP directs action of hormone
Response (protein)
-result of hormone direction
Thyroid Regulation
-thyroid hormones regulate homeostasis
-iodine required for thyroid function
-Triodothyronin (T3) requires three iodine atoms
-Thyroxine (T4) required four iodine atoms
-lack of iodine causes more TSH production which causes enlarged thyroid
Parathyroid Hormone
-control of blood calcium
-regulate homeostasis of calcium
-released by parathyroid glands
-increases level of calcium in blood
Thyroid gland
-releases calcitonin
Calcitonin
-released by thyroid gland
-decreases level of calcium in blood
Glucose Homeostasis
-insulin and glucagon regulate breakdown of glycogen in glucose
Insulin
-secreted in pancreas by beta cells
-lowers blood sugar
-causes storage of glucose and glycogen
Glucagon
-secreted in pancreas by alpha cells
-increases blood sugar
-breaks glycogen down into glucose
Adrenal Hormones
-caused by stress
-epinephrine/adrenaline produced by adrenal gland
Asexual reproduction
-all offspring come from one parent
-creation of offspring without fusion of egg and sperm
Sexual reproduction
-offspring are mix of two parents
-fusion of haploid egg and haploid sperm into diploid zygote
Fission
-growth in width
-separation of parent into two offspring
Budding
-new offspring arise from outgrowths of parent entity
Fragmentation
-breaking of body into several pieces
-each piece grows into full adult
Parthenogenesis
-development of offspring from unfertilized egg
Hermaphroditism
-each individual has female and male reproductive system
External Egg fertilization
-spawning
-eggs shed by female and fertilized by male in environment (frogs, salmon)
Internal Egg Fertilization
-sperm is deposited in or near female reproductive system
-fertilization happens in female reproductive tract
Male Reproductive Organs
-XY
-Y chromosome contains SRY gene
-SRY codes for male; testes production
-sperm is formed
Female Reproductive Organs
-XX
-no SRy gene
-ovary production
-eggs formed
Male gonads
-testes
-consist of seminiferous tubules
-sperm form in seminiferous tubules
-sperm stored in epididymis
Semen
-sperm (testes)
-lubricating mucus (Bulbourethral Gland)
-sugar (seminal vesicle)
-buffers (prostate gland)
Female Gonads
-ovaries
-contain many follicles
-each follicle contains an ovum
-females born with all eggs
-one egg released every month
Menstrual Cycle
-Follicular Phase
-Ovulation
-Luteal Phase
Follicular Phase
-menstruation occurs
-due to breakdown of endometrium
-ovum matures in ovary
Ovulation
-follicle ruptures to release ovum
Luteal Phase
-corpus luteum forms from ruptured follicle
-endometrium thickens for possible pregnancy
-if corpus luteum degrades, endometrium will degrade
