Chapter 29 Flashcards
Cyanobacteria and protists likely existed on land __________ years ago
1.2 Billion
Around __________ years ago, small plants, fungi, and animals emerged on land
500 million
Land plants are defined as having __________ ancestors, even though some are now _______
Terrestrial; aquatic
Land plants share what four characteristics with only charophytes
1) Rings of cellulose-synthesizing proteins
2) Structure of flagellated sperm
3) Formation of a phragmoplast
4) DNA
Bryophytes
Non-vascular plants
Spermatophytes
Seed plants
Embryophytes
Land plants
Streptophytes
Green plants
In charophytes, a layer of a durable polymer called __________ prevents exposed zygotes from drying out
sporopollenin
Land presented challenges: a _______ of water and lack of ____________
scarcity; structural support
Five key traits appear in nearly all land plants but are absent in the charophytes
1) Alternation of generations
2) multicellular, dependent embryos
3) Walled spored produced in sporangia
4) Multicellular gametangia
5) Apical meristems
Alternation of generations
the process by which plants alternate between two multicellular stages; a reproductive cycle
gametophyte
haploid and produces haploid gametes by mitosis
sporophyte
Arises from the fusion of gametes; produces haploid spores by meiosis
Embryophytes
the name for land plants; given because of the dependence of the embryo on the parent
Cuticle
a waxy covering of the epidermis
Stomata
specialized cells that create pores which allows for gas exchange between the outside air and the plant
Mycorrhizae
symbiotic associations between fungi and land plants; may have helped plants without true roots obtain nutrients
A
Cuticle
B
Upper Epidermis
C
Palisade Layer
D
Spongy Mesophyll
E
Lower Epidermis
F
Cuticle
Fossil evidence indicates that plants were on land at least __________ years ago
470 million
Fossilized spores and tissues have been extracted from _______________
450-million-year-old rocks
Fossils of larger structures, such as sporangium, date to __________ years ago
425 million
Land plants can be informally grouped based on the presence or absence of _________
vascular tissue
vascular plants
Plants that have vascular tissues
Nonvascular plants are commonly called ________
bryophytes
The two clades of vascular plants
- Lycophytes
- Monilophytes
Lycophytes
Club mosses and their relatives
Monilophytes
ferns and their relatives
A grade
a group of organisms that are together based on shared key biological features, rather than shared ancestry
The three phyla of bryophytes
- Hepatophyta
- Bryophyta
- Anthocerophyta
Hepatophyta
liverworts
Bryophyta
Mosses
Anthocerophyta
Hornworts
T/F: In Bryophytes, sporophytes are dominant and are longer lived and larger
False; the gametophyte is dominant
Xylem
vascular tissue that conducts most of the water and minerals
Tracheids
tube-shaped cells found in the xylem
lignin
strengthen and support water-conducting cells
Phloem
vascular tissue that has cells arranged into tubes that distribute sugars, amino acids, and other organic products
Roots
organs that anchor v vascular plants
Leaves
organs that increase the surface area of vascular plants, thereby capturing more solar energy that is used for photosynthesis
Microphylls
leaves with a single vein
Megaphylls
leaves with a highly branched vascular system
Sporophylls
modified leaves with sporangia
Sori
clusters of sporangia on the undersides of sporophylls
Strobili
cone-like structures formed from groups of sporophylls
