Fusion of egg and sperm initiates what within the egg?
Cortical Reaction
What is polyspermy?
It induces multipolar spindle assemblies and disrupts mitotic division. The fertilization envelope acts as a slow block to polyspermy which is deadly. Fast block is electrical barrier depolarization. NO FAST BLOCK in mammals
What is capacitation?
Spermatazion maturation
Holoblastic vs Meroblastic cleavage:
(Holoblastic) complete division of the egg, little yolk, examples: sea urchins, frogs, and annelids. (Meroblastic) incomplete division of egg, lots of yoke, examples: birds, fish, insects
3 Germ Layers
- Ectoderm outer
- Endoderm digestive tract
- Mesoderm fills space between other 2
Totipotent:
All types of cells including placenta
Pluripotent:
All BUT placenta
Multipotent:
more limited, adult stem cells/cord blood cells
Saltatory Conduction
action potential in myelinated axons jump between nodes of Ranvier
Oligodendrocytes
myelin sheaths made by gila, insulating sheath on nerve fibers
What is the botulinum toxin:
causes botulism, reduces the synaptic release of acetylcholine (muscle paralysis)
5 Groups of Neurotransmitters:
acetylcholine, biogenic amines, amino acids, neuropeptides, and gases (Nitric Oxide)
Known to function in the CNS:
Glutamate (excitatory), Gamma-aminobutyric acid (GABA, operates at most inhibitory synapses in the brain), Glycine (inhibitory)
What are Neurons?
Nerve cells that transfer information within the body
3 STAGES OF NERVOUS SYSTEM PROCESSES
- Sensory (input/reception)
- Integration (integrating center)
- Moter output (effectors vis motor neurons)
Central Nervous System CNS:
where integration takes place; includes brain and nerve cord
Peripheral Nervous System PNS:
carries information in and out of CNS
Synapse:
Junction between an axon and another cell
Cone shaped base of an axon is called:
axon hillock
Membrane potential of a neuron not sending signals:
Resting Potential
During Resting Potential:
K+ is highest inside cell, Na+ is highest outside cell
What is the body’s automatic response to a stimulus:
reflex
What animals DO NOT have a central nervous system?
Animals that have radial symmetry example: sea sponges
Gray Matter:
unmyelinated
What functions to cushion the brain and spinal cord as well as provide nutrients and remove wastes:
Cerebrospinal fluid
White Matter:
myelinated
2 Components of PNS:
motor system signals to skeletal muscles and is voluntary, autonomic nervous system regulates smooth and cardiac muscles involuntary
Sympathetic division:
fight or flight
Enteric division:
digestive tract, pancreas, gallbladder
Parasympathetic division:
rest and digest
Medulla oblongata:
respiration and circulation (breathing, heart rate, blood vessel, digestion, sneezing, swallowing)
Hypothalamus:
links nervous system to endocrine system via the pituitary gland (parenting, hunger, thirst, sleep)
Brainstem:
diffuse network of neurons called the reticular formation (amount and information that affects alertness, melatonin)
Functional regions of the cerebral cortex:
Frontal Lobe: speech, movement, emotions
Parietal Lobe: sensory input from skin, skeletal muscles, understanding speech
Occipital Lobe: seeing, perception of visual stimuli
Temporal Lobe: hearing, perception, auditory stimuli
Neural Plasticity:
ability of nervous system to be modified after birth
DISORDERS OF NERVOUS SYSTEM:
Schizophrenia, depression (Fluoxetine), drug addiction, Alzheimer’s (destroy myelin sheath), Parkinson’s (death of dopamine-secreting neurons)
Brain reward center:
nucleus accumbens
Sexual reproduction:
creation of offspring by fusion of male gamete (sperm) and female gamete (egg) to form a zygote
Asexual reproduction:
creation of offspring without fusion of egg and sperm
What is fission:
separation of a parent into two or more individuals of about the same size.
What is Parthenogenesis:
development of new individual from an unfertilized egg, examples: bees, whiptail lizards, Komodo dragon, hammerhead sharks
Ovulation:
release of mature eggs at midpoint of a female cycle
What is hermaphroditism:
one individual has a male and female reproductive system
Oogenesis:
the process in which an oocyte develops into an ovum once a month, development of a mature egg
Spermatogenesis:
development of sperm
Parkinson’s:
muscle tremors even at rest, flexed posture, slowness of movement, a shuffling gait/posture instability
What is the amygdala?
structure most important for storage of emotion in the memory
Define Menopause:
cessation of ovulation and menstruation