Final Exam pre Midterms Flashcards
Split Brain Surgery
Done to alleviate epileptic seizures. Sever the corpus callous. The hemispheres can’t communicate directly with one another. Coordinated movement is still possible thanks to the brainstem and spinal cord.
Corpus callosum
The bundle of white matter tracts connecting the left and right hemispheres.
Cerebral Hemispheres
Consciously process sensory information and initiate purposeful movement.
Lateralized function of cerebral hemisphere
Left brain:
- Control of muscles on right half of the body
- Couple language comprehension, speech, writing
- Processing right half of visual field
Right brain:
- Control of muscles on left half of the body
- Limited language, small ‘dictionary’
- Processing left half of visual field
Vision and the Hemispheres
When focusing on a fixation point, vision is divided into a left and right visual field:
The left visual field is processed by the right half of each eye. The right visual field is processed by the left half of each eye.
Nasal half of visual information (half closer to the midline) crosses over at the optic chasm.
Left hemisphere of brain processes right visual field. Right hemisphere processes left visual field.
Gazzaniga’s Interpreter Theory
In experiments with split brain patients, researchers give a visual command to the nonverbal right brain. Then ask the patients to verbally explain why they had done that thing. The left brain would create a story to explain the behaviour. Gazzaniga theorized that this is how unified conscious experience arises. Our behaviour is out of our control (no free will). The left brain develops a meaningful narrative through which we can understand our experiences.
Atoms
Every element is a type of atom. Atoms can and to form molecules. If an atom or molecule has a charge, it is an ion.
CHNOPS
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur
The CHNOPS elements form 5 main molecules
Water, sugar, fat (lipids), nucleic acids, amino acids.
RNA
Single stranded chain of nucleic acids. Fragile. Ribozymes: Subgroup of RNA that catalyze chemical reactions. Thought to give rise to first life on Earth.
DNA
Double stranded chain of nucleic acids. Stable. In eukaryotes, stored safely in the nucleus. Primary storage of genetic info today.
Cell membrane
Phospholipid bilayer. Hydrophilic (water loving) phosphate head. Hydrophobic (water hating) lipid tail. The structure makes diffusion across the membrane difficult - a good thing if you want an enclosed cell.
Prokaryotic Cells
Single cell organisms. Cell membrane filled with cytoplasm (salty, nutrient filled liquid inside a cell). DNA, RNA, and ribosomes floating around.
Eukaryotic Cells
Single- or multi-cell organisms. Contains organelles like mitochondria and nucleus. Can now store DNA and create energy.
Protein Synthesis
- A segment of DNA in the nucleus is unraveled and a complementary strand of RNA is created (mRNA) - Transcription.
- mRNA leaves the nucleus
- Ribosome latches onto mRNA, recruits tRNA to bring in complementary amino acids - Translation.
- Amino acids are added to a growing chain that eventually breaks off and folds into a protein.
What is a neuron
A specialized type of cell that is electrically excitable. Neurons send electrical and chemical signals that permit fast communication.
Reticular Theory (Golgi)
Believed that the brain was a physically connected network
Neuron Doctrine (Cajal)
Believed that the brain was composed of individual cells communicating.
Soma
Cell body. Location of the nucleus and other organelles.
Dendrites
Sites for receiving chemical or sensory input.
Axon
Electrical signals (action potentials) are sent down the axon. Only one axon, but that axon can branch many times.
Axon terminals
End of axon, where the action potential triggers the releases of neurotransmitter.
Phospholipid Bilayer
Cell membrane. Ions cannot move across it. Hydrophilic (water loving) phosphate head. Hydrophobic (water hating) lipid tail. Inside: Cytosol (salty like solution filled with potassium, chloride, and sodium).
What makes a cell specialized?
All cells within an organism have the same DNA. Not all cells read the same sections of DNA. A section of the DNA (the gene) codes for a certain protein (strings of amino acids). Other sections of DNA define what cells should read the gene and when. Neurons are filled with proteins that determine the cell’s role.