part 1 Flashcards
word equation for photosynthesis
carbon dioxide + water = glucose + oxygen
describe how energy for photosynthesis is gained by plants
- light shines on palisade layer
- palisade cells of palisade mesophyll tissue has lots of chloroplasts
- contains chlorophyll absorbs sunlight
how did the student deal with the anomylous result?
- observe scale better
- ask someone else to read it
give one factor the students should have kept constant in this investigation
light intensity
why did the rate of photosynthesis decrease from 35 to 40 degrees?
the enzymes are damaged
what is diffusion?
the random movement of particles from an area of high concentration to an area of low concentration until equilibrium is reached
what increases the rate at which carbon dioxide diffuses into the mesophyll cells?
- decreased chloroplasts
- stomata
explain how the lungs are adapted for efficient exchange of gases by diffusion
- contains alveoli and surrounded by network of blood capilleries
- maximises diffusion of substances
- give lungs large surface area:more contact
- thin walls: shorter diffusion distance
- moist, permeable walls: gas dissolve
- extensive blood supply: deoxygenated blood to lungs, oxygenated away
- large diffusion gradient: higher concentration oxygen in alveoli move to blood
how does root hair cell use active transport?
- carrier proteins in cell membrane
- absorb nitrate ions from dilute solution in the soil
- against a concentration gradient
- uses energy from respiration
similarities between prokaryotic and eukaryotic cells
- cytoplasm
- ribosomes
give 3 differences between the prokaryotic and eukaryotic cell
- prokaryote has a single loop of dna and plasmids
- prokaryote has no chloroplasts but mesophyll cell does
- prokaryote is smaller
ratio between bacteria and mesophyll cell
- 0.05 is 50 micrometers
- 1:50
what is stage 1 of the cell cycle?
- interphase
- dna spreads out in long strings
- before divides, cell grows and increases subcellular structures eg mitochondria
- duplicates DNA forms X-shaped chromosomes
what is stage 2 of the cell cycle?
- chromosomes line up at centre
- cell fibres pull them apart
- two arms of each goes to opposite ends of cell
- nucleus divides as membrane froms around two nuclei
what is stage 3 of the cell cycle?
- cytoplasm and cell membrane divides
- two daughter cells
- same dna
- identical to parent cell