1.2. Physical Basis of Heredity Flashcards
• Cell Structure and Genetic Function • Chromosomes • Major Processes Involved in the Genetic Continuity of Nucleated Cells
cell structure that houses the dna
nucleus
site of rRNA synthesis and the initial stages of ribosome assembly
nucleolus
site of translation
ribosome
site of atp synthesis; contains dna
mitochondria
site of photosynthesis; contains dna
chloroplast
coiled chromatin fibers
chromosome
extended form of the chromosome
chromatin fiber
centromere in the middle
metacentric
centromere between middle and end
submetacentric
centromere is close to end
acrocentric
centromere is at the end portion
telocentric
chromosomes that have the same size, shape, position of centromere, gene sites along their lengths, and characteristics
homologous chromosomes
homologous chromosomes all carry the same information. true or false?
false; not necessarily the same
major process in genetic continuity that leads to the production of two cells with the same number of chromosomes as the parent cells; involves somatic cells
mitosis
what are the roles of mitosis?
(1) growth and development
(2) regeneration and repair
(3) basis for asexual reproduction for unicellular organisms (i.e., protozoa, fungi, algae)
constitutes the events that occur from the completion of one division until the completion of the next division
cell cycle
what happens in the g0 stage?
cells are dormant; cells are viable and metabolically active but do not proliferate; reversible or irreversible
cells spend most of their time in interphase. true or false?
true. they spend 15 hours in interphase(5 for g1, 7 for s phase, and 3 for g2 phase. only one hour is spent for mitosis
g1/s checkpoint checks for
cell size and dna quality
g2/m checkpoint checks for
dna replication and quality
m checkpoint checks for
spindle assembly checkpoint
no visible chromosomes but visible nucleolus; nuclear membrane starts to disintegrate
interphase
interphase
(1) chromatin number
(2) chromosome number
(3) chromatid number
(1) 92 chromatins/cell
(2) 0 chromosome/cell
(3) 0 chromatid/cell
visible chromosomes; complete disintegration of nuclear membrane; asters/star-like arrangement of microtubules; spindle fiber assembly
prophase
cohesin is formed during what stage?
interphase
prophase
(1) chromatin number
(2) chromosome number
(3) chromatid number
(1) 0/cell
(2) 46/cell
(3) 92/cell
period of chromosome migration to the equatorial plane called the metaphase plate; migration is facilitated by the binding of spindle fibers to the chromosome’s kinetochore
prometaphase