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Flashcards in Ch 19 Deck (13):
1

Prokaryotic DNA

DNA is "naked" not complexed with proteins; negative charges neutralized by calcium ions; short circle of DNA; only 3,000 genes; few introns and mRNA processing is simple

2

Eukaryotic DNA

has nucleosome histones and forms chromosomes; each DNA molecule is long and can carry thousands of genes; contains introns and large segments of DNA do not code for any type of RNA

3

Organelles

prokaryotes lack membrane bound organelles; only have ribosomes and storage granules in their cytoplasm; eukaryotes have nuclei and mitochondria and plants and algae have plastids

4

Endosymbiont theory

the theory that plastids and mitochondria arose as prokaryotes that were living symbiotically within an early eukaryotic cell; prokaryotes evolved to the level of having a membrane-bound nucleus

5

Origin of Mitochondria

the early eukaryotes engulfed but did not digest a prokaryote, which then evolved into a mitochondrion

6

Origin of Plastids

some descendants of that early eukaryote would engulf but not digest a prochlorophyte type of cyanobacterium, which would evolve into a plastid

7

Spore (n)

a single cell that is a means of asexual reproduction; it can grow into a new organism but cannot fuse like a gamete

8

Gametophyte (n)

a haploid plant that produces gametes

9

Fertilization (n + n -> 2n)

fusion of two gametes (egg and sperm)

10

Zygote

the diploid cell formed as the result of the fusion of two gametes

11

Sporophyte (2n)

a diploid plant that produces spores

12

Sporangium (2n)

a structure that produces spores

13

Meiosis (2n -> n+n)

reduction division; a process in which nuclear chromosomes are duplicated once but divided twice; chromosome number is reduced; becomes independent chromosomes