CHAPTER 11 AND 12: FINALS REVIEW Flashcards
What is a charcater trait?
Physical, psychological, or physiological attribute that varies from one individual to another within the same species
What is the difference of chromatin and chromosomes?
Chromatin- mass of DNA and protein within the nucleus when a cell is not undergoing division
vs.
Chromosome- rods of condensed chromatin that is formed when a cell is undergoing division
what are homologus pairs?
pairs of chromosomes that are similar to eachother in size and shape
What is a karyotype?
a representation of an individual’s chromsomes by grouping them into homologus pairs
What is DNA made up of?
nitrogenous bases (A,T,C,G), sugars (deroxyribose), and phosphate bases
What is a gene?
DNA segment containing information (series of nitrogenous bases) for making a specific protein
What is a genome?
all genes received by an organism’s parents
what is a protein?
molecule that plays a specific role in the body and in the expression of character traits
What are amino acids?
molecule that combines in chains to create proteins
What is the difference between DNA and RNA?
DNA: in a double-helix formation, has bases A T C G, has deoxyribose sugar, Bases are linked with weak H bonds
RNA: in a single strand, has bases A U C G, has ribose sugar
What is protein synthesis? What are its steps?
Protein synthesis is the creation of protein by cells.
- Transcription of DNA into messenger RNA: DNA is unzipped, MRNA is built by copying nucleotide sequence
- Attachemnt of the MRNA to the ribosome: MRNA attaches itself to a ribsome. Ribosome slides over MRNA and reads nucleotides in triplets. Protein synthesis begins when start codon is read
- Translation of MRNA into protein: Triplets are red by ribsosome, amino acid is linked one after another by TRNA
- End of protein synthesis: UAA, UAG, UGA is read, the chain is complete. protein is released from ribosome.
What is heredity?
The transmission of parents’ character traits to their offspring
What is a pure line?
group of individuals of the same species who produce offspring with the same character trait without variation
What is crossbreeding?
exchange of gametes between two individuals during sexual reproduction
What is a hybrid?
Individual obtained by the crossbreeding of two genetically different individuals
What is a generation?
group of individuals descended from common parents
What is an allele?
Possible form of a gene. Alleles all have different nucleotide sequences
what is the difference between a homozygote and a heterozygote?
Homozygote: individual with two identical alleles for a character trait
Heterzygote: individual with two different alleles for a character trait
What are the differences between dominant and recessive alleles?
Dominant allele: allele that is expressed as a character trait when someone carries two alleles for the same gene
Recessive allele: allele that is not expressed as a character trait when someone carries two alleles for the same gene
What is the difference between a genotype and a phenotype?
Genotype: individual’s genetic inhertitance, expressed in alleles (e.g., B for brown eyes)
Phenotype: describes the appearance (e.g., brown eyes)
True or false: recessive alleles are represented by a capital letter
False
What is a constraint?
the effect of external forces on a material?
What are the main constraints?
Compression, defelction, tension, torsion, shearing
What are the three types of material deformation?
Elastic (constraint causes temporary change) , plastic (constraint causes permanent change) , and fracture (constraint causes material to break)
What is a component?
part or fluid that performs a mechanical function
What is linking?
mechanical function performed by any component that connects the different parts of an object
What are the characteritics of a link?
Direct (can hold without a linking component) vs indirect (requires a linking component to stay together)
Rigid vs flexible (linking component and surfaces can be deformed like springs or rubber)
Removable (linked parts can be sperated without damage) vs non-removable (linked parts cannot be seperated)
Complete (linked parts cannot move independently) vs incomplete (at least one part can move independently)
What is a motion transmission?
mechanical function of relaying a motion from one part to another without transforming the motion
What is a motion transmission system?
set of components that perform the fucntion of motion transmission
What are the three components in a mechanical system?
Driver, driven, and the occasional intermediate component
What are the five common motion transmission systems?
Gear trains, chain and sprocket systems, worm and worm gear systems, friction gear systems, and belt and pulley systems
Which motion transmission systems are irreversible (diver can become driven and vise versa) ?
Worm and worm gear systems
What are elelments to consider when making a gear train?
all teeth must be identical, rotationla axi sof gears can be positioned in different ways, larger gears = slower rotation, more teeth= slower rotation
What are elelments to consider when making a chain and sprocket system?
teeth and sprockets must be identical, chain link must mesh easily with sprocket teeth, system needs lubrication, smaller sprocket= faster rotation
What are elelments to consider when making a worm and worm gear system?
worm grooves must fit w/ the gear teeth, worm will always be the driver
What are elelments to consider when making a fcition gear system?
there are straight, bevel, and spherical fiction gears, larger diameter= slower roation, friction must be higjh to avoid slipping of gears (need of adhesive materials)
What are elelments to consider when making a belt and pulley system?
pulleys must contain groove where belt can fit, belt must adhere to pulleys, smaller pulleys = faster rotation
How do speed changes occur?
when the driver does not turn at the same spped as the driven component(s)
How do speed changes occur in worm and worm gear systems?
one full turn of a worm= worm gear moves an equal distance of one tooth. Therefore, more teeth on the gear= slower speeds
How do speed changed occur in other motion transmission systems?
When motion is transmitted from one component to one with…
Smaller diamater/few teeth = speed increase
larger diamteter/many teeth= speed decrease
same diamteter/teeth = no change
How do you calculate speed ratio?
diameter or teeth of driver/ diameter or teeth of driven
What is the difference between engine torque and resisiting torque?
engine torque: increases rotational speed
resisting torque: slows or stop rotation
When engine torque is greater than resisting torque, speed…
increases
