Reproduction & chromosome transmission Flashcards
Reproduction
Process where new cells or new organisms are produced
Chromosomes
Structure within living cells that contain the genetic material (Genes are located within the chromsomes because DNA is in the chromosomes)
Chromatin
Is the DNA strain that is wrapped within a chromosome
Prokaryetes
SIngle celled organism that dont have a nucleus
Prokaryetes chromsomes are not contained in the nucleus instead are contained in the __________
Nucleiod
Eukaryotes
Contain membrane bound organelle & a nucleus
Cytogenetics
A field of genetics that involves the microscopic examination of chromosomes
Human have ______ chromsomes
23 (total of 46)
Karyotype
AN organized representation of the chromosome within a cell
Eukaryotic cells are ________
Diploid- each type of chromsome is a # of a pair
A diploid cell has ________ of chromosome
2 sets ( like in a human has 46 chromosome 2 sets of 23 chromosomes)
Homologs
Are the pair of chromosome within a diploid cell (The two sets of chromosomes are identical so whatever is found in one pair is in the other pair)
Alleles
Are two chromosomes in a pair that carry different verisons of a given gene
_____ chromosomes X & Y are not homologous chromosomes
Sex Chromosomes
__________ reproduction is how unicellular organism reproduce
Asexual
Bateria reproduce (divide) asexually by ___________
Binary Fusion
Eukaryotic cells divide by a process called __________
Cell cyle
What are the phases in the cell cyle?
- G phase (Gap phase, G1 & G2)
- S phase (Synthesis phase)
- M phase (Mitosis phase)
Cells in the _______ phase are either temporarily not moving through the cell cycle or will never divide again
G0
The G0 phase is the __________
Non-dividng phase
During the _____ a cell is prepared to divide where it will come to a restriction point & if it passes through will move on to the other stages
G1
After the cell past the restriction of the G1 it goes on to the _______ where the chromosome is replicated (DNA Transcription & translation)
S phase
After the S phase the two copies (chromatids) are joined to each other at the centromere to form _____________
Sister chromatids (Dynad)
A single chromatid in a dynad is called a ________
Monad
After the _____ phase a cell has twice as many chromosomes than it orginally had
S phase
Kinetochore
A group of proteins that are bound to the centremere
The ___________ hold the sister chromatids together & also help sort chromosomes
Kinetochore
During the _____ phase the cell accumulates the materials that are necessary for nuclear & cell division
G2
After the G2 phase the cells goes to the _____ phase where yhr replicated cells are distributed to the daughter cell
M phase
The two daugther cells are formed by a process called ____________
Cytokinesis
The ______________ organizes & sorts eukaryotic chromosomes
Mitotic spindle
Mitosis
THe transmission of chromosomes during divison of eukaryotic cells
What are the phases of Mitosis
- Prophase (the chromosome replicated)
- Prometaphase
- Metaphase
- Anaphase
- Telophase
In plant cells the two daugther cells are seperated by a process called ________
Cell plate
__________ & ___________ produces two daughter cells having the same number of chromosomes as the mother cell
Mitosis & Cytokinesis
Meisois
Haploid cells (which only contain one set of chromosomes) are produced from cell that was originally diploid
_________ produces cells that are haploid
Meiosis
What are the phases of meiosis?
- Leptotene
- Zygotene
- Pachtene
- Diplotene
- Diakinesis
During the ________ stage the replicated chromosomes begin to condense & become visble with a light microscope
Leptotene
The Zygotene stage involves a process called __________
Synapsis
Synapsis
The homologus chromosomes recongnize each other & begin to align themselves along their entire lengths
At the ___________ stage the homologs have become completely aligned where the chromatids are known as bivalents
Pachytene
Each _________ contains two pairs of sister chromatids or a total of 4 chromatids
Bivalent
A bivalent is also called a _______ because it is composed of four chromatids
Tetrad
Before the pachytene stage & after synopsis is complete an event called _____________ occurs
Crossing over
Crossing over
Involves a physical exchange of chromosome pieces that results in an exchange of genetic information
In the ___________ stage the synaptonemal complex completely disappears
Diakinesis
After prophase os meisosis 1 ___________ occurs where the spindle appartus is completely formed & the chromatids are attached by kinetochore microtubules
Prometphase
In the __________ of meiosis 1 the bivalents are organized along the metaphase plate where they are randomly aligned in the middle but in 2 rows
Metaphase
During the _________ of meiosis 1 the two pairs of sister chromatids within a bivalents seperate from each other
Anaphase
What happens in the anaphase of meiosis 1
The two dyads(chromosomes) within the tetrad seperate from each other & migrate to opposite sides
At the _________ phase of meiosis 1 the sister chromatidshave reached their respective poles & decondensation occur
Telophase
During __________ the cells that begins __________ begin with 3 dynads (in mitosis it begins with 2 dynads)
Meiosis 2
The daughter cells produced in ________ are genetically identica but not in ________
Mitosis, Meiosis
During ____________ gametes are made that contain half the amount of an organism’s gentic material
Sexual reproduction
Gametogenesis
Process that produces gametes
Gametes are usually ________
Haptoids
Haploids gametes contains ___________ set of chromsomes
A single set
Diploid contains ________ of chromosomes
2 Sets
Most eukaryotic species are _____________
Heterogamous- they produce two morphologically different types of gametes (Males gametes (sperms) & Female gametes (egg cells)
Spermatogenesis
The production of sperm that occur in the testes
Oogensis
