lecture 3

Question 1

what are bryophytes

Answer 1

nonvascular land plants (mosses, liverworts, hornworts)

Question 2

what new evidence has come up about bryophytes

Answer 2

in past years bryophytes were not a clade but now they are seen as a clade and are equally related to vascular land plants

Question 3

what are the main characteristics of bryophytes

Answer 3

1. they have NO true ROOTS, STEMS or LEAVES, 2. have no strong support tissue plant body 3. obtain and move water in a undirected fashion 4. they have signaling protein involved in desiccation tolerance 5. have swimming sperm with two tails

Question 4

what is desiccation tolerance

Answer 4

they can voluntarily dry out and shut down cells to preserve water and open up again when in contact with water

Question 5

what are the key adaptions for colonization for bryophytes

Answer 5

they live in moist areas, small so they dont need to move water too far, can live on rocks and buildings, small enough to get minerals through diffusion, and have relationship with fungi

Question 6

what is gametangia

Answer 6

organs that make and enclose gametes an prevent them drying out

Question 7

what are archegonium

Answer 7

creates female eggs through mitosis

Question 8

what are antheridium

Answer 8

creates male sperm through mitosis

Question 9

what is an embryo

Answer 9

young plants contained with a protective structure

Question 10

sporangium

Answer 10

makes spores through meiosis

Question 11

what is a gametophyte

Answer 11

haploid adult dominant form of bryophyte

Question 12

what is a sporophyte

Answer 12

diploid adult , dependent on gametophyte for nutrition, needs water to be splashed to move sperm

Question 13

what are the three bryophyte linages

Answer 13

mosses, hornworts, and liverworts

Question 14

what are characteristics of liverworts

Answer 14

1. green flat leaflike gametophytes 2. growth occurs at the apex 3. no true stomata so no internal water conduction 4. has unique parallel ridges 5. 2 sperm tails

Question 15

what are characteristics of liverworts sporophytes

Answer 15

sporophyte has a stalk and a capsule (sporangium), stalk elongates rapidly by cell elongations, they have elaters

Question 16

what are elaters

Answer 16

assists in dispersal flexible in response to change in humidity

Question 17

what are characteristics of mosses

Answer 17

erect, leafy gametophytes, have stomata, have cells called hydroids and have peristome teeth

Question 18

what are hydroids

Answer 18

cells that die and leave a channel through which water can move

Question 19

peristome teeth

Answer 19

they line the apex of the capsule or sporangium and change shape with humidity and moves spores

Question 20

what are characteristics of hornworts

Answer 20

the sporophytes look like small horns, the cells contain one chloroplast, and the sporophyte grows from the basal region capable of indefinite cell division, THEY HAVE A SYMBIOTIC RELATIONSHIP WITH CYANOBACTERIA TO FIX NITROGEN

Question 21

what are characteristics of moss Sphagnum**

Answer 21

the sporophyte capsule pops off, large in ecologically and economically are (good in short summer), the sphagnum removes a lot of CO2 and burns well when its dry, it is used for fertilizer, whiskey, and burning