CH8 Flashcards
How many chromatids in one chromosome?
2
How many centromeres in one chromosome?
1
Name the six phases of the cell cycle in order.
Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis.
How many chromosomes do humans have?
46
How many autosomes do humans have?
44
What is an autosome?
Non-sex chromosome.
If the diploid number of an organism is 10, how many chromosomes would you expect to find in each cell in telophase of mitosis?
10
If the diploid number of an organism is 10, how many chromosomes would you expect to find in each cell in telophase II of meiosis?
5
What are the two sex chromosomes of a human female?
xx
What are the two sex chromosomes of a human male?
xy
What’s a karyotype?
A picture of all homologous chromosomes all paired up.
Define homologous.
Similar in size and genetic content.
Is MITOSIS involved in reproduction?
No, meiosis is, because it produces sex cells.
Is mitosis happening right now?
Yes, because we are constantly growing, as proven in cell division.
What are stem cells?
Undifferentiated cells that can become any kind of cell.
In which phase of mitosis do the chromosomes line up at the equator of the cell?
Metaphase.
Is prophase the phase that takes the longest?
No, interphase is the longest because it is preparing to divide by copying DNA.
When in the cell cycle, does DNA get copied?
Yes, during metaphase.
What kind of cells are haploid cells?
Sex cells.
What kind of cells are diploid cells?
Body/somatic cells.
In which phase of the cell cycle does the nuclear membrane dissapear?
Metaphase.
In which phase of the cell cycle do chromosomes uncoil and go back to chromatin?
Telophase.
What are the two types of human gametes?
Sperm and egg cells.
Cell division occurs __________.
Continuously.
Cell differentiation occurs __ ________ __________.
In embryonic formations.
Define duplication.
Selection of chromo is repeated.
Define deletion.
Selection of chromo is deleted.
Define inversion.
Selection of chromo is inverted/flipped.
Define translocation.
Two chromos switch places.
Define non-disjunction.
Extra/missing whole chromo.
What are the two causes of mutations?
- Errors in DNA.
2. Exposure to mutagens (UV light, cigarette smoke, or radiation etc).
Are mutations good or bad? Explain.
Both.
- Good = If a new trait makes survival easier.
- Bad = Disease, cancer, or death.
What happens if the signals that regulate the cell cycle are ignored?
Mutated cells continue to reproduce, along with a large amount of regular cells. This is also known as cancer.
Define oogenesis.
Meiosis that specifically makes egg cells.
Meiosis produces ___ ____, which join in a process called _____________ to produce the fertilized egg called a(an) ______.
- Sex cells.
- Fertilization.
- Zygote.
Differentiate gene mutation and chromosomal mutation.
Chromosomal mutations are larger than gene mutations.
What is cell division?
The process in which one cell splits and becomes two cells; occurs continuously and is used for growth and repair.
What is cell differentiation?
The process in which cells become specialized to preform specific tasks; occurs in embryonic formations.
Compare and contrast sexual reproduction and asexual reproduction.
- Sexual reproduction consists of 2 parents and a random, split DNA.
- Asexual reproduction consists of one parent and identical DNA between the parent and the daughter.
What is a centromere?
The center/meeting point of two chromatids.
What is a chromatid?
Half of a chromosome.
Where does cell division occur in?
Prokaryotes.
Describe interphase.
The longest part of the cell cycle, cell prepares to divide by copying DNA.
Define mitosis.
The end of interphase signals; the beginning of mitosis (cell division).
Describe prophase.
- Chromatin condenses into chromosomes.
2. Spindle fibers are seen coming from centrioles; they pull chromos around.
Describe metaphase.
- Chromosomes line up in the middle.
2. Nuclear membrane disappears.
Describe anaphase.
- Chromosomes separate.
2. Each chromatid moves to opposite poles.
Describe telophase.
- Chromosomes begin to uncoil and go back to chromatin.
2. Nuclear membrane reforms.
Describe cytokinesis.
The division of cytoplasm and cell membrane.
The chromosome number is ________ during mitosis.
Maintained.
