Bio general Flashcards
use ideas about atoms ions and the transfer of electrons to explain the formation during electrolysis
one electron moves from ion to anode // ions attracted to anode
How white blood cells defend against disease
Produce antibodies // responsible for phagocytosis // antibodies destroy pathogens
roles of mitosis
growth, repair of damaged tissue, asexual reproduction, replacement of cells
compare direction of movement of substances during translocation and transpiration
transpiration occurs upwards from root to leaf // translocation occurs up and down the plant
role of enzymes in the chemical digestion that occurs in the mouth
amylase breaks down starch // to simple sugars // large insoluble to smaller soluble MOLECULES
differences between selective breeding & natural selection
SB : humans select the desirable features // faster process // results in less variation // inbreeding is more common
effect of ciliated cells dying, on the gas exchange system
alveoli get blocked // reduces area for gas exchange // goblet cells produce mucus // mucus traps bacteria // cilia unable to remove mucus // decreases surface area of gas exchange // bacteria multiply // causing infection // breathing difficulties
why nitrate increases plant growth
nitrate needed to make amino acids
amino acids needed for protein synthesis
proteins are needded for growth which increases the yield
uses of carbohydrates made during photosynthesis
reactant for respiration
to make cellulose for cell walls
converted to sucrose for transport
how skin responds to cold temperatures to maintain constant internal body temp
vasoconstriction // arterioles narrow // blood flow to surface capillaries reduced // less heat lost by radiation // hair stands on end
why is chlorophyll needed for photosynthesis
transfers light energy to chemical energy // to synthesise carbohydrates
features of placenta that enable efficient gas exchange
thin membrane // large surface area // good blood supply // permeable membrane
mitosis vs. meiosis
chromosome produced by MITOSIS have a diploid number
cells produced by MITOSIS contain two sets of chromosomes , are paired / cells produced by MEIOSIS are unpaired
cells produced by MITOSIS are GENETICALLY identical to parent cell
features of alveoli that make them efficient gas exchange surfaces
good blood supply, thin, large surface area, ventilated
difference between artificial selection & natural selection
A - traits selected by humans
- usually chosen for economic reasons ( N : beneficial for survival)
- faster results
- takes place in selected individuals (N takes place in whole populations)
- does not lead to evolution
results in decreased genetic variation
- leads to increased likelihood of genetic disease
