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neurotransmitters vs. hormones
both are chemical messengers
neurotransmitters: transmit a message from a nerve cell across the synapse to a target cell
hormones: secreted directly into blood which carries them to organs and tissues of the body
epinephrine
- commonly called adrenaline
constricts blood vessels, increases heart rate, but also relaxes airway muscles (making it easier to breathe)
serotonin
used by body to send messages between nerve cells
- plays role in mood and emotion, regulates sleep-wake cycle and body clock
(known for happiness, focus, and calmness)
dopamine
pleasure hormone
also involved in ability to think and plan
endorphins
- used to cope with pain and stress
- pain reliever and happiness booster
“feel good” chemical
ways of transmission:
- AIDS
- Tuberculosis
- Dengue Virus
- Cholera
AIDS: sexual transmission, spread of bodily fluids
Tuberculosis: spreads from person to person through microscopic air droplets (coughing and whatnot)
Dengue Virus: spreads through mosquito bites
Cholera: spreads by drinking contaminated water or food
Hemophilia (+ inheritance pattern)
bleeding disorder that slows blood clotting process
- inherited in an X-linked recessive disorder
Co-dominant alleles
2 different alleles contribute to a particular characteristic would express themselves in a collaborative manner, phenotype is a combination the 2 different phenotypes
which type of cells have no cell walls?
liver cells
(fungal and bacterial cells have cell walls)
70S Ribosomes vs. 80S Ribosomes
70S Ribosomes: found in prokaryotic cells (including bacteria)
80S Ribosomes: found in eukaryotic cells (plants, animals, fungi, and protists)
According to the fluid mosaic model of the cell membrane, which zone is embedded inside?
hydrophobic
tissue
group of cells that have similar structure and function together as a unit
4 functions of the endoplasmic reticulum
- produces proteins
- involved in making lipids (fats)
- Detoxifies the cell by breaking down harmful chemical and drugs
- Stores and transports proteins and lipids within the cell
which cell organelle is involved in the synthesis of cell wall and middle lamella?
Golgi apparatus
(plays crucial role in processing, modifying, and packaging various cell materials including the ones for the cell wall)
hydrophobic exclusion
water likes to stay from hydrophobic things
- helps maintain the structure of things like cell membrane and keep them stable
water acts as a universal solvent because of
high polarity
lipids store double the amount of energy as compared to carbohydrates because
high proportion of C-H
(explanation: C-H bonds release more energy than breaking C-O bonds. lipids store more energy because they have a higher proportion of C-H bonds and less of C-O bonds)
unsaturated vs saturated fatty acid
unsaturated: contains one or more carbon double bonds
saturated: every carbon atom is attached to as many hydrogen atoms as it can be
monosaccharides have a general formula represented by
(CH2O) n
n carbon atoms and b H2O molecules
NAD
stands for “Nicotinamide Adenine Dinucleotide”
- dinucleotide
- helper that makes sure cells get their energy by moving around electrons
most enzymes have an optimum temperature of around
40 C
Calvin cycle
used by plants to help convert carbon dioxide into energy using sunlight and water
first stable compound during Calvin cycle is
3-phosphoglycerate
which is a copper containing protein in electron transport chain?
plastocyanin
allele (genetics)
partner of gene pair
loci (genetics)
the position of a gene on the chromosome
loci
the position
phenotype and genotype
phenotype: the form of appearance of a trait
genotype: the genetic component i.e. the genes in an individual for a particular trait
which is found in both messenger RNA and DNA of a mammalian cell?
sugar - phosphate backbone
DNA & RNA polymerase
DNA polymerase: copies DNA exactly
RNA polymerase: transcribes an RNA copy of the DNA
the particular array of chromosomes that an individual possesses is called its
karyotype
during meiosis, the homologous chromosomes come together and form pairs, this process is called
synapsis
at what cell division phase is the DNA content doubled?
interphase (S-phase which occurs during interphase)
transcription and translation
transcription: the formation of mRNA out of DNA
translation: synthesis of proteins using those mRNAs
endosymbiotic theory
some of the organelles in today’s eukaryotic cells were once prokaryotic microbes
- mitochondria and chloroplasts
analogous vs homologous organs
analogous organs: similar function but different structures (ex. flippers and webbed feet)
homologous organs: different function but similar structures (ex. arms of humans and flippers of whales)
recombinant DNA
DNA that has been altered and which now contains length of nucleotides from 2 different organisms
polymerase chain reaction (PCR)
technique used to rapidly increase the number of copies of specific regions of DNA for further analysis
DNA ligase
connects individual DNA fragments together by forming phosphodiester bonds between them
name the 3 components/tools of recombinant DNA technology
gene of interest (part of the DNA that’s being modified), molecular scissors, molecular glue and expression system
gel electrophoreses
laboratory method used to separate mixtures of RNA, DNA, or proteins according to molecular size
(molecules separated are pushed by an electrical field through a gel that contains small pores)
transgenic organisms
- created through genetic engineering
- gene from one species inserted into DNA of another
- used to artificially engineer things like insulin
- beneficial to humans
the end product in anaerobic respiration is
2 types of anaerobic respiration:
lactic acid fermentation: end product is lactic acid
alcohol fermentation: end product is carbon dioxide and ethanol
final answer: lactic acid, carbon dioxide, and ethanol
enveloped virus
virus that an outer wrapping or “envelope”
- envelope is derived from the host which helps it hide from antibodies as it travels (antibody resistant)
- survive for a short time
opportunist disease
disease that takes advantage of a weakened immune system
(would not otherwise be successful if the immune system was up to par)
a complete, mature infection virus particle is called
Virion
(main function is to deliver its DNA or RNA genome into the host cell so that the genome can be expressed in the host cell)