Lecture 17 Flashcards
Cells that have one full set (copy) of all chromosomes are _________
Haploid (N)
Cells that have 2 sets (copies) of all chromosomes are _______
Diploid (2N)
Cells have 3 sets (copies) of all chromosomes are _______.
Triploid (3N)
Cells that 4 have sets of chromosomes are _______.
Tetraploid (4N)
are life cycles a sexual or asexual process?
sexual
what are the two steps of eukaryotic cell divison?
nuclear division and cytoplasmic division
the nuclear division step of eukaryotic cell division includes what processes?
mitosis and meiosis
the cytoplasmic division step of eukaryotic cell division includes what processes?
cytokincaia
Nuclear division resulting in two cells, each with nuclear genetic material identical to the original cell
mitosis
is there a change in chromosome number in mitosis?
no
is there a change in ploidy in mitisos?
no, ploidy remains the same the entire time (2N–> 2N+2N or N–> N+N)
Nuclear division that results in four cells, each with only 1/2 the genetic information of the original cell, and each with a different subset of the genetic material in the original cell.
Meiosis
what is an example of a ploidy change in meiosis
2N–>N+N+N+N
what kind of cells are formed by mitosis?
vegetative cells
Reproductive cells
Spores
gametes
can gametes undergo fertilization
yes
can spores under go fertilization?
no, only mitosis
syngamy
fertilization
what kind of cells are formed by mitosis?
Reproductive cells
Spores
gametes
how many types (styles) of life cycle are there?
3
how do the different types of life cycles differ from each other?
•Differ in timing of meiosis and mitosis.
•Differ in ploidy of free-living stage(s).
(diploid, haploid, both)
what is the ploidy of a gamete?
N
what is the ploidy of a zygote?
2N
what is the ploidy of the cells produced by meiosis?
N
what is the ploidy of the cells produced by fertilization
2N
what are the different forms of gametes that we see in nature?
Isogamy, anisogamy, oogamy
Isogamy
both gametes are identical in size and both are motile by flagella.
Anisogamy
gametes are different sizes, both gametes are motile by flagella.
Oogamy
large non-motile egg, smaller motile sperm.
is the haploid or diploid phase dominant in a diplontic life cycle
the diploid phases
which phase is multicellular and free living in a diplontic life cycle
the diploid phases
what produces gametes in a diplontic life cycle
meiosis
are there spores in a diplontic life cycle?
no
what kind of organisms undergo gametic meiosis?
animals, some protists, and algae
is the haploid or diploid phase dominant in a haplontic life cycle
the haploid phase
describe the haploid phase of a haplontic life cycle
- Multicellular
- long lived
- Free living
what is the diploid stage of a haplontic life cycle
a zygote
what kind of meiosis does an organisms that has a haploid life cycle undergo
zygotic meiosis
what produces spores in an organism with a haplontic life cycle
meiosis
what produces gametes in an organism with a haplontic life cycle
mitosis
what kind of organisms have zygotic meiosis
fungi, some algae
which stage of the sporic life cycle is free living and usually multicellular
both the haploid phase and diploid phase
what kind of meiosis does an organisms that has a sporic life cycle undergo
sporic meiosis
what does meiosis produce in organisms with a sporic life cycle
spores
what does mitosis produce in organisms with a sporic life cycle
gametes
which type or life cycle has an alteration of generations
a sporic life cycle
what are the variations of the sporic life cycle
isomorphic generations
heteromorphic generation
what are isomorphic generations
sporophyte and gametophyte look similar
what is a gametophyte?
the gamete producing stage (N)
what is a sporophyte?
the spore producing stage (2N)
what are heteromorphic generations?
the sporophyte and gametophyte look different
example of an organism with heteromorphic generations
the laminaria
example of an organism with isomorphic generations
the ulva
