Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
70 Cards in this Set
- Front
- Back
During cell division, the DNA in a eukaryotic cell is tightly packed and coiled into structures called____________
|
chromosomes
|
|
Between cell divisions, the DNA in a eukaryotic cell is uncoiled and spread out; in this form it is called
|
chromatin
|
|
The chromosomes of most prokaryotes consist of proteins and
|
a single circular DNA molecule.
|
|
Humans have 46 chromosomes in all cells except sperm and egg cells how many of these chromosomes are autosomes?
|
44
|
|
If an organism has a diploid or 2n, number of 16, how many chromosomes do its sperm cells or eggs cells contain?
|
8
|
|
What role do proteins play in enormous amount of DNA in a eukaryotic cell to fit into the nucleus and what are those proteins called?
|
Histones help coil and package the DNA into a very small volume
|
|
In what ways are homologous chromosomes similar
|
the same size and shape and carry genes for the same traits.
|
|
What 2 chromosomes do females carry?
|
XX
|
|
What 2 chromosomes do males carry?
|
XY
|
|
What is it called when you take a picture of the chromosomes
|
Karyotype
|
|
Histone proteins
|
help maintain the shape of a chromosome and aid in the tight packing of DNA
|
|
chromatid
|
is one half of a chromosome
|
|
centromere
|
is the constricted area of a chromatid that holds the two chromatids in a chromosome together
|
|
autosome
|
is any other chromosome
|
|
sex chromosome
|
is a chromosome that determines the sex of an organism
|
|
diploid cells
|
has both chromosomes in each homologous pair
|
|
haploid cell
|
has only one chromosome in each homologous pair.
|
|
what are tightly coild DNA molecules?
|
Chromosomes
|
|
What help maintain the compact structure of chromosomes?
|
histone protein
|
|
T/F Chromosomes in prokaryotes are simpler than chromosomes in eukaryotes
|
true
|
|
T/F All creatures and organisms have the same number of chromosomes.
|
F
|
|
cells having two sets of chromosomes are called _______
|
diploid (2n)
|
|
cells that have 1/2 the number of chromosomes that are present in diploid cells are __________
|
haploid cells (1n)
|
|
What is one main difference between prokaryotic and a eukaryotic?
|
Prokaryotic has only one chromosome
|
|
How many chromosomes do humans have?
|
46
|
|
How many sexual chromosomes do humans have?
|
2
|
|
Explain what is chromatin
|
Where the instructions are in the long strands
|
|
Is DNA A NUCLEIC ACID?
|
yes
|
|
Where is the DNA found in eukaroytic cell?
|
nucleus of a cell
|
|
What helps the DNA to coil?
|
histone proteins
|
|
Prokaryotic cells reproduce by a process called
|
binary fission
|
|
In eukaryotic cells, DNA is copied during a phase of the cell cycle called?
|
S phase
|
|
The cytoplasm of a eukaryotic cell divides by a process called
|
cytokinesis
|
|
The fibers that extend from centrosome to centrosome during mitosis are
|
polar fibers
|
|
What happens to the cells in the G.o phase?
|
exit from the cell cycle
|
|
What are the 5 main phases of a cell cycle?
|
G 1 phase
S Phase G 2 phase Mitosis or M phase Cytokinesis |
|
What does the G1 phase do?
|
Cell growth
|
|
What does the S phase do?
|
DNA is copied
|
|
What does the G2 phase do?
|
cell prepares for cell division
|
|
What does the M phase or mitosis do?
|
nucleus divides
|
|
What does the Cytokinesis phase do?
|
cytoplasm divides
|
|
List the four phases of mitosis
|
1. prophase
2. metaphase 3. anaphase 4. telophase |
|
What happens in the prophase?
|
the chromatin coils and forms chromosomes, the nucleolus and nuclear envelope disappear. and the mitotic spindle forms
|
|
What happens in the metaphase?
|
kinetochore fibers move the chromosomes to the cell equator.
|
|
What happens in the Anaphase?
|
the chromatids in each chromosome separate and move toward the opposite poles of the cell.
|
|
What happens in the telophase?
|
the mitotic spindle disappears and the chromatids unwind to form chromatin, the nuclear envelope reforms and a nucleolus appears.
|
|
Describe cytokinesis in a plant cell
|
Vesicles formed by the Golgi apparatus fuse at the midline of the cell to form the cell plate, a cell wall that elongates to separate the cell into 2 cells.
|
|
One large chromosomes and a series of smaller rings of DNA in a Prokaryotic cells is called?
|
plasmids
|
|
Do muscle cells and brain cells copy themselves?
|
No
|
|
What is an example of which kinds of cells keep copying themselves and can not stop?
|
Cancer cells
|
|
What is an example of which cells stop at G1 and does not keep repairing and building cells.
|
Spinal cord
|
|
Where does the cell spend most of its time carrying out its job before mitosis?
|
Interphase
|
|
What is it called when it is a programmed cell death? If a call fails to replicate itself properly, they will take themselves out of the cycle.
|
apoptosis
|
|
Is Mitosis involved in reproduction process?
|
No, meiosis is.
|
|
What is the function of mitosis?
|
is to evenly divide the DNA to the daughter cells
|
|
What kind of division has to happen with a diploid cell to become a fully functional multi-celled organism?
|
Mitotic divison
|
|
What is the purpose of meiosis?
|
is to make haploid cells for reproduction.
|
|
How many haploid cells are there in meiosis?
|
23 from each parent
|
|
What produces haploid cells in reproduction ?
|
meiosis
|
|
What are the 2 kinds of reproduction processes?
|
asexual and sexual reproduction
|
|
What are the names of the structure that produce haploid cells?
|
Gonads
|
|
What are the 2 different types of gonads in male and female?
|
male is the testes --sperm cells
female is the ovaries--egg or ova cells |
|
A sperm cell + egg cell = ????
|
zygote cell
|
|
What is the most complex stage in the meiosis I phase?
|
prophase I stage
|
|
What are a few differences in meiosis I compared to mitosis.
|
1. Synapsis happens-pairing of homologous chromosomes
2. tetrad are made--each pair of homologous chromosomes 3. The HC line up face to face 4. Crossing over occurs-exchanges ends 5. Regegentic recombination |
|
What does crossing-over means in meiosis I?
|
This is where they exchange instructions on the ends of the chromatids.
|
|
During the anaphase I in meiosis, do the chormosomes line up independently or in order?
|
independently
|
|
What is the difference with the starting prophase II and Prophase I in meiosis?
|
Prophase II starts with 2 haploid cells
Prophase I starts with a diploid cell |
|
What are some differences between Prophase I and Prophase II?
|
In Prophase II, there is no homologous chromosomes coming together.
2. No crossing over 3. No tetrad 4. No replication |
|
During the telophase II phase in meiosis, how many new cells are formed?
|
4
|