Lecture 1- plant physiology

Question 1

what do plants need to grow

Answer 1

CO2

Question 2

primary function of roots

Answer 2

aquisition of soil based resources (water and ions)

anchoring plants

Question 3

secondary functions of roots

Answer 3

storage
synthesis of hormones
propogation

Question 4

some stats on roots - mass %

soil volume

Answer 4

40% of mass

5% of soil volume

Question 5

shape and depth determined by

Answer 5

genetics

Question 6

growth and distribution governed by

Answer 6

soil moisture
.soil temp
profile
o2
toxins
nutrients

Question 7

root tips will grow in what direction

Answer 7

positive moisture gradient

Question 8

what do the root tips produce during water stress

Answer 8

abscissic acid

Question 9

what does abscissic acid do and where is it produced

Answer 9

root tips, it closes the stomata

Question 10

three purposes of stems

Answer 10

display leaves to light
transport from roots to leaves
sometimes storage of water food etc

Question 11

purpose of flowers/fruit

Answer 11

reproduction and storage

Question 12

write the photosynthesis equation

Answer 12

ok

Question 13

more stomata on underside or top

Answer 13

more on underside (lower evap on bottom side so have more)

Question 14

when do stomata open or close

Answer 14

depends on water content and humidity

Question 15

how do stomata open and close

Answer 15

concentration of K changes (potassium ) -get flow of water into cells (opens)
out of cell (closes)

Question 16

what is crop development, crop growth, and how does the latter occur

Answer 16

development- progress from germination to maturity

growth- increase in size- due to new cells

• expansion of cells
• production of assimilates

Question 17

what are the 7 development stages

Answer 17

seeding
germination
emergence
vegetative stage
reproductive phase
ripening phase
harvest

Question 18

what are the four phases to the development of a seedling

Answer 18

imbibition -absorption of water
breaking of seed coat
first root
first leaf

Question 19

what is the vegetative phase

Answer 19

green leaves+ photsynthesis= dry matter production

Question 20

what does the rate of photosynthesis depend on

Answer 20

irradiance
co2 concentration
temperature
water status

Question 21

reproductive phase

Answer 21

flowering
pollination
fruit setting
maturity

Question 22

growth rate stages

Answer 22

lag period from sowing
exponential
linear
zero
negativeq

Question 23

2 main and other influences on growth rate

Answer 23

temp
photoperiod

light c02 nutrients toxins water

Question 24

what are the ranges for base temp, optimum temo, and max temp

Answer 24

0-5 base
20-25 optimum
35-45 max

Question 25

what is the thermal period

Answer 25

amount of time T between base and max limits

Question 26

how does the photoperiod effect growth

Answer 26

photosynthesis
induction of flowering
suitability for growing outside normal zone

Question 27

draw how the rates of photosythesis changes for varying light intenisty, and vary temp (two light intensities)

Answer 27

ok

Question 28

how does c02 affect growth

Answer 28

reduction in stomatal conductance
improve water use efficiency
higher photo synth rates
increased light use efficiency

Question 29

what is defined as the rate that co2 enters the stomata

Answer 29

stomatal conductance

Question 30

what are some macro nutrients

Answer 30

C H O
N P K
ca mg S

Question 31

micro nutrients

Answer 31

fe ma cu zn B cl

Question 32

draw graph of nutrient effect on growth

Answer 32

ok

Question 33

nutrient uptake dependent on

how is absorbed

Answer 33

nutrient avalability in soil
nutrient aquisition of plant

liquid phase only

Question 34

what is the soil nutrient supply dependent on

Answer 34

soil solution concentration
soil buffer power
soil water holding capacity
soil bulk density 
soil temperature

Question 35

5 roles of water in the plant

Answer 35

photosysnthesis
control temp
structural support
transport of gases 
makes up organs

Question 36

what is crop water use broken up into

Answer 36

99%transpiration

1% tissue