PERIODICAL EXAM

• Nervous System

  • Central nervous system (Brain and spinal cord)
  • Peripheral nervous system
  • Autonomic nervous system (communicates with internal organs and glands)
  • Somatic nervous system (communicates with sense organs and voluntary muscles)
  • Sympathetic division (arousing)
  • Parasympathetic division (calming)
  • Motor (efferent) nervous system (motor output)
  • Sensory (afferent) nervous system (sensory input)
• Nervous System

  The master controlling and communicating system of the body. It controls and coordinates all essential functions of the human body.
• Central Nervous System (CNS)

  The main processing center for the entire nervous system.
• Three Main Parts of Brain

  • Cerebrum
  • Cerebellum
  • Brainstem
• Cerebrum

  • Controls thinking, planning, organizing, problem-solving, short-term memory and movement
  • Interprets sensory information, such as taste, temperature and touch
  • Processes images from your eyes and links information with images in memory
  • Processes information from your senses of smell, taste, and sound, and plays a role in memory storage
• Cerebellum

  • Helps your muscles to coordinate your movement and your balance
• Brain Stem

  • Controls many autonomic functions, including breathing, blood pressure, and heart rate
  • Allows passage of nerve fibers between brain and spinal cord
• Spinal Cord

  • Serves as a channel for signals between the brain and the rest of the body, and controls simple musculoskeletal reflexes without input from the brain
• Peripheral Nervous System (PNS)

  Connects the central nervous system to the organs and limbs
• Somatic Nervous System

  • Spinal nerves – nerves that carry motor and sensory signals between the spinal cord and the body
  • Cranial nerves – serve fibers that carry information into and out of the brain stem
• Autonomic Nervous System

  • Sympathetic – activated when the body is in dynamic role or stress (e.g., increased heart rate and breathing, dilation of pupil, sweating, etc.)
  • Parasympathetic – maintains body function and restores the body to normal or relaxed mode
• Nerve Cell

  The basic unit of the nervous system, also called neurons. They are like cables that carry electrical impulses between your brain and the rest of your body.
• Nerve Cell

  • Dendrites carry impulse towards the cell body
  • Axons carry impulses away from the cell body
• Nerve Impulse

  A combination of an electric charge and a chemical reaction. It is an electrochemical signal moving along a neuron.
• Nerve Impulse

  1. Nerve impulse comes to the end of an axon

  2. Produces the chemical, called neurotransmitter

  3. Neurotransmitter crosses the space between neurons called synapse

  4. Stimulates the nerve impulse to start in the next dendrite
• Stimulus

  Any factor in the environment that may trigger a nerve impulse
• Response

  A reaction to a stimulus
• Menstruation is the periodic discharge of blood and cellular debris from the female genital tract
• Menstrual cycle

  Cyclic changes occurring from one menstruation to the next
• The duration of menstrual cycle is about 28 +/- 4 days
• Follicular Phase

  1. Starts on day 1 of menstruation and ends with ovulation (day 14)

  2. Brain (anterior pituitary) sends Follicle Stimulating Hormone (FSH) to ovaries to signal follicles to grow and mature

  3. Follicles produce estrogen

  4. Estrogen acts on uterus to stimulate thickening of endometrium (uterine lining)

  5. When estrogen peaks, it signals brain to release Luteinizing Hormone (LH)

  6. LH triggers ovulation
• Ovulation

  Mature egg from follicle travels from ovary down to fallopian tube and into uterus
• If fertilization does not occur during ovulation, the egg continues to the uterus and dies within 6 to 24 hours
• Luteal Phase

  1. Includes the day after ovulation to the day before next period

  2. LH and FSH levels decrease

  3. Empty follicle develops into corpus luteum which produces progesterone

  4. If egg isn't fertilized, corpus luteum degenerates and estrogen level decreases

  5. Hormonal changes associated with premenstrual syndrome (PMS) symptoms
• Menstruation is important in a woman's body
• The ovary releases an egg on the 14th day of a 28 day cycle
• If there is no fertilization, the egg will disappear
• Estrogen

  Hormone that causes the uterine lining to increase in thickness
• Pituitary gland

  Gland that controls and starts the menstrual cycle
• Hormones that assist in maturation of follicles

  • FSH
  • LH
  • GnRH
  • Estrogen
• DNA

  Deoxyribonucleic acid that stores and transmits the genetic information from one generation of an organism to the next
• Nucleotide

  Building block of DNA, composed of one phosphate group, the sugar deoxyribose and one of the four bases Adenine, Thymine, Cytosine and Guanine (A, T, C, G)
• RNA

  Ribonucleic acid, a nucleic acid that differs from DNA in three ways: it is single stranded, the sugar is ribose, and it contains uracil (U) instead of thymine
• Types of RNA

  • Messenger RNA (mRNA)
  • Ribosomal RNA (rRNA)
  • Transfer RNA (tRNA)
• mRNA

  Brings information from the DNA in the nucleus to the protein manufacturing area, the cytoplasm
• rRNA

  Holds tightly into the mRNA using its information to assemble the amino acids in correct order
• tRNA

  Supplies amino acids to the ribosome to be assembled as protein
• DNA Replication

  1. Helicase breaks the bond between nitrogenous bases

  2. Bases attach to free nucleotides in cytoplasm

  3. DNA polymerase adds complementary nucleotides to form new strands
• Transcription

  1. RNA polymerase enzyme binds and opens the DNA molecules

  2. RNA polymerase links free RNA nucleotides that pair with nitrogenous bases of the complementary DNA strand

  3. RNA molecule breaks away as the DNA strands rejoin
• Translation

  1. mRNA binds to a ribosome

  2. tRNA anticodon pairs with the first mRNA (start) codon AUG

  3. Ribosome slides along the mRNA to the next codon

  4. New tRNA molecule carrying an amino acid pairs with the second mRNA codon

  5. Enzyme joins the first and second amino acids by forming a peptide bond

  6. Process continues until ribosome reaches a stop codon on the mRNA strand