Chapter 3 - Chromosomes transmission Flashcards
What are chromosomes composed of?
- DNA
2. protein
What is chromatin?
It is DNA - protein complex
Does prokaryotic cells have nuculus?
No, it doesn’t
Does prokaryotic cell have membrane bounded organelles?
No, it doesn’t
Does prokaryotic cells have cytoblasm?
Yes, its cytoplasm enclosed by membrane.
Does prokaryotic cell have rigid wall?
Yes, it has rigid wall outside the membranes
What are the two types of animal cells?
- somatic cells
2. gametes cells
What is the cytogenetic?
It is the field that involves microscopic examination of chromosomes.
What are the differences between chromosomes in homologous pair?
- They are identical in size.
2. Have the same banding pattern and centromere location.
What are the characteristic of sex chromosomes?
- They are not homologous.
- They differ in size and genetic composition.
- They have short region of homology.
What are the two purposes in cell division?
- asexual reproduction
2. achieving multicellularity.
How does the prokaryotic cell reproduce?
They reproduce asexually by binary fission.
How many cells does the binary fission produce?
They produce two daughter cell by process of binary fission.
What is the function of FTsZ protein?
It recruits other proteins to create new cell wall that separate the two mother cells into two daughter cells.
What phases are included in interphase?
- G1 phase
- S phase
- G2 phase.
What happens during G1 phase?
A cell prepare to divide.
What happens during S phase?
Chromosomes are replicated
What happens during G2 phase?
The cell accumulate the material that are necessary for nuclear and cell division.
What happens during M phase?
Cell goes through mitosis.
What is a dyad?
It is a pair of sister chromatid.
What is monad?
It is one chromatid.
What is the purpose of mitosis?
The primary purpose of mitosis is to distribute the the replicated chromosomes to the two daughter cells.
What are the five phases of mitosis?
- prophase
- prometaphase
- metaphase
- anaphase
- telophase.
What is the centrosome?
It is the attachment point of the mitotic spindle.
How is the spindles are made?
They are formed by rapid polymerization of tubulin protein.
What are the three types of microtubules spindles?
- Aster microtubules
- polar microtubules
- Kinetochore microtubules
What is the function of Aster microtubules?
They position the spindle appartus
What is the function of polar microtubules?
They push the poles away from each other.
What is the function of Kinetochore microtubules?
They attach to the kinetochore which is bound to the centromere of each individual chromosomes.
What happens during Prophase?
- nuclear envelope dissociates into small pieces.
- chromatid condense into more compact structure
- centromeres begin to separate
What happens during prometaphase?
- centrosomes move to the opposite ends of the cell forming the spindle pole.
- spindle apparatus form
- Kinetochore microtubules grow from the poles.
How does the spindle apparatus form?
The spindle fibers interact with the sister chromatids.
What happens during metaphase?
- pair of sister chromatids align themselves along a plane called the metaphase plate.
- Each pair of chromatid are attached to both poles by kinetochore microtubules.
What happens during Anaphase 1?
- the connection that is holding the two sister chromatids together is broken.
- Kinetochore microtubules shorten
- polar microtubules lengthen
What happens during telophase?
- The chromosomes reach their respective pole and decondense.
- nuclear membrane reform to from two separate nuclei
What happens to plants during cytokinesis?
They from cell plate
What happens to animal during cytokinesis?
They from cleavage furrow.
What is the outcome of mitotic cell division?
Two genetical identical daughter cells.
What are the 5 phases of prophase 1?
- leptotene
- zygotene
3 pachytene - diplotene
- diakinesis
What happens during Leptotene?
The replicated chromosomes condenses.
What happens during zygotene?
Synapsis begin
What happens during Pachytene?
A bivalent has formed and crossing over has occurred.
What happens during diplotene?
Synaptonemal complex dissociates
What happens during diakinesis?
End of prophase 1
What is the isogamous?
Some Eukaryotic cells that produce gametes that morphologically identical.
What is heterogamous?
most Eukaryotic cell that produce gametes that are morphologically different.
What does the head of sperm contains?
it contains a haploids nucleus, and a digestive enzyme
what is the function of the digestive enzyme in the sperm?
It enables the sperm to penetrate the protective layer of the egg.
When the does the primary oocytes intiates?
It initiates in meiosis 1
