Download Plants without Seeds A54-65

Science Notes for Ch. 3 Plant Diversity
Lesson 5- Plants without Seeds
What are mosses? (p. A58-59)
-nonvascular plants= don’t have tubelike structures
-tiny plants that are only 1-2 inches tall
-only 1 or 2 cells thick
-have no roots or seeds
-have rhizoids= hairlike fibers that take in water from their surroundings
-have spores= cells that grow into new organisms
What are ferns? (p. A60-61)
-have fronds= leaves
-grow above ground
-have rhizomes= underground stems
-reproduce with spores
How do the life cycles of mosses and ferns differ? (p. A62-63)
-asexual reproduction= stage of life cycle that produces spores using only 1 type of cell,
the spore
-male branches of spores produce sperm (male sex cells)
-female branches of spores produce eggs (female sex cells)
-fertilization= process when male and female sex cells join together
-sexual reproduction= stage in cycle when plant needs both male and female sex cells to
reproduce
-alternation of generations= process of going from sexual to asexual reproduction
What were the ancestors of plants? (p. A64-65)
-1st land plants developed from algae about 420 million years ago and were nonvascular
similar to mosses
-earliest vascular plants were ferns that were seedless and developed about 315 million
years ago
-first plants with seeds were gymnospores about 275 million years ago
-angiosperms are flowering plants that first developed about 130 million years ago