Lecture 7

Question 1

adventitious shoots/roots

Answer 1

roots/shoots which grow along the stem/ any non-root tissue

Question 2

monocot vs dicot roots

Answer 2

monocots have fibrous roots, dicots have a single tap root with laterals

Question 3

what is meristem

Answer 3

regions with undifferentiated cells that can continue dividing (stem cells)

Question 4

totipotency

Answer 4

cells that can continue divide and differentiate ex. spores and zygotes

Question 5

what are cells in the meristem like

Answer 5

they are small and densely cytoplasmic

Question 6

what are root buds

Answer 6

roots that produce shoots

Question 7

what is suckering

Answer 7

lateral roots formed from stems and give rise to other erect stems underground; from above it looks like a ton of trees

Question 8

what are ramets

Answer 8

multiple genetically identical stems (clones); part of suckering

Question 9

what are prop roots

Answer 9

roots which arise from the lower side of branches and hold u the plant as it spreads and gets heavy
- ex. ficus trees

Question 10

what are aerial roots

Answer 10

prop roots, before they make contact with the earth (when theyre still hanging down)

Question 11

what is clonal propagation

Answer 11

tree that spreads to create a large colony comprising of thousands of trees around itself (arises due to prop root formation and thickening)

Question 12

what are stilt roots

Answer 12

grow from basal nodes of some monocots and mangrove trees

- emerge from lower nodes than prop roots and contact the ground at an angle

Question 13

what are buttress roots

Answer 13

aerial extensions of lateral roots; buttress the trunk by spreading all around it in a shallow soil

Question 14

why are carrots, beets, etc a thing

Answer 14

it is a major survival strategy - food reserves underground (mostly starch)

Question 15

what is an example of a tap root

Answer 15

carrot, turnip, beet

Question 16

what is an example of a tuberous root

Answer 16

sweet potato

Question 17

what are cluster roots

Answer 17

when a ton of extensions form from the main root (looks like a pipe cleaner)

Question 18

what are runners (stolon)

Answer 18

stems that spread on top of the soil and produce adventitious roots on the nodes

Question 19

what are rhizomes

Answer 19

horizontally extending stems that run below the soil and have clear nodes, internodes, shoot buds, and adventitious roots
- ex ginger

Question 20

what are tubers

Answer 20

thickened rhizomes or stolons, where new shoots sprout from the nodes and adventitious roots grow on the lower side

Question 21

what is a bulb

Answer 21

compressed, concave, fleshy leaves surrounded by outer scaly leaves and enclosing shoot buds borne on a compressed stem
- onion, tulip

Question 22

what is a corm

Answer 22

solid, have fibrous as well as contract roots

- taro, eddoes

Question 23

what are bulbils

Answer 23

tiny bulbs borne on a scape that look like a flower but do not get pollinated
- ex garlic

Question 24

what is a scape

Answer 24

a long leafless stalk growing out from an underground bulb, corm, rhizome

Question 25

what is vivipary

Answer 25

when an embryo starts germinating prematurely on a parent plant
(bulbil makes leaf and roots while still attached)

Question 26

what is somatic embrogenesis

Answer 26

formation of an embryo without pollination and fertilization (no gametes involved)
- considered an embryo bc it has two meristems (SAM and RAM)

Question 27

can somatic embryogenesis occur under natural conditions

Answer 27

yes! when the environment doesn’t allow for flowering or if the plant gets cut in some way you might see tiny structures hanging onto the stem without going through the process of forming a flower or embryo

Question 28

what are epiphytes

Answer 28

plants growing on other plants

Question 29

what are xerophytes

Answer 29

cacti and succulents; have true leaves that shrivel up under harsh conditions to make spikes