Chapter 8 Flashcards
The cellular basis of reproduction and inheritance
________________ Is the biological creation of the next generation.
Reproduction
reproduction occurs primarily at the ________________.
cellular level
Cell division is critical for the continuing replacement of __________________.
ageing or lost.
Cell division is critical for the production of additional cells to allow ________ and __________.
growth and reproduction
Cell division is called_____________.
mitosis
There are two types of reproduction, _____________ and ___________ reproduction.
asexual; sexual
During asexual reproduction there is ___________________________.
no exchange of genetic material.
An organism reproduces by making an ____________________.
exact copy of itself.
Most prokaryotic organisms reproduce asexually in a process called ______________.
binary fission
During _______________________, two organism exchange genetic material to produce a new generation of organisms that is similar.
sexual reproduction
During sexual reproduction, two organisms exchange genetic material to produce a new generation of organisms that is similar.
This exchange may be accomplished by __________ of eggs and sperm or direct DNA exchange (as in many Unicellular organisms)
fertilization
To achieve fertilization, gametes (eggs and sperm) are produced by gonads, and they ____________.
must be used
The production of gametes is a series of 2 cellular divisions called __________.
meiosis
Each cell contains all of the genetic information that makes up an organism, this molecular information is know as the___________.
Genome
Each cell contains all of the genetic information that makes and organism, most of this information is located in the nucleus of ______________.
eukaryotic cells
What are the two primary functions of a cell?
Conduct metabolic activities and divide to create more cells.
What is the metabolic phase called?
Interpahse
What is the reproductive phase called?
Mitotic phase
Metabolic activity and synthesis of enzymes.
G1: Gap phase.
All chromosomes are duplicated
S phase; DNA synthesis
Chromosomes divide and cell division occurs
M phase; Mitotic phase
Production of microtubules important for cellular division
G2 phase Last stage before mitosis
Chromosomes are assembled from DNA strands plus several ________ proteins.
histone
When chromosomes are assembled from DNA strands plus several histone proteins this assemblage is called___________.
Chromatin
During_______, when the DNA needs to be active, the chromosomes are _______.
interphase; unwound
When DNA needs to be replicated before ________, the chromosomes are ___________, like a ball of string.
mitosis, tightly wound
DNA has a _________ charge.
Negative
_____ is coiled and folded several times enabling this extremely long molecule to be packaged into a tiny ______.
DNA; Nucleus
In preparation for _______, all of the genetic material is replicated.
Mitosis
The resulting two copies of the DNA are __________________.
Sister chromatids
During Mitosis the sister chromatids are,___________ and __________ to different daughter cells.
Separated and distributed
After __________, the genetic material must be divided so that cell_______ can occur.
interphase; division
The steps leading up to a cell division are collectively known as ____________.
Mitosis
During mitosis, spindle fibers formed by the cells _________ attach to the chromosomes at structures called ________ and guide the chromosomes into position.
Certrioles; Kinetochores
The chromosomes are first moved to the middle of the cell by ____________.
Mitotic spindles
The spindle fibers then separate the chromosomes into two identical sets by moving them to the __________ of the dividing cell.
Polar end
What order does mitosis occur in?
Prophase metaphase anaphase telephase cynkinesis
What happens in the early Prophase and what step does this occur?
Mitotic spindle form
1st
What happens in the late prophase and what step does this occur?
Chromosomes compact
nuclear envelope breaks
1st
What happens in Metaphase and what step does this occur?
Chromosomes compact, move to middle of cell also mitotic spindle attaches to chromosomes at kinrtochore.
2nd
What happens in Anaphase and what steps does this occur?
Mitotic spindle shortens, pulls chromosomes to opposite ends of the cell.
This is the 3rd phase
What happens in the Telophase and Cytokinesis and what step does this occur?
mitotic spindle disintegrates, nuclear envelope begins to form again, and cell divides
________ is the final step in cell formation.
Cytokinesis
Cytokinesis is typically coincides with_________.
Telophase
During cytokinesis, the ________ is split up as the new cells are completed.
Cytoplasm
In animals, cytokinesis occurs by __________.
Cleavage
Cleavage “_______” the cell apart.
Pinches
In plants, ________ with cell wall material accumulate at the cell midline.
Vesicles
Vesicles with cell wall material accumulate at the cell midline, these vesicles form a ________________.
Membranous cell plate
Once the ends of the cell plate are connected to the cell wall, ______ cells have been formed.
two
The cell cycle operates as a control device for cell ___________ and ___________.
development; growth
__________ (cancer causing agent) or genetic may interrupt or change the timing of the cell cycle as a cell growth.
Carcinogens
Carcinogens may cause to reproduce at the wrong time or in the wrong place, causing _________.
Tumor growth
A __________ is a mass of defective cells that remains cohesive in its place of origin.
Benign tumor
A _________ is a spreading tumor, whose cells may spread to other parts of the body.
Malignant tumor
______ cells divide rapidly and may spread to other organs and tissues.
Cancer
_________ is the spread of cancer to other places.
Metastasis
What types of treatments are available for treating cancer?
Surgery (‘slash”) removes
Radiation therapy (“burn”) disrupts cell division
Cheotherapy (“poison”) uses drugs that disrupt cell division of fast-dividing cancer cells
What is the fundamental purpose of sex?
Reproduction
What is the cellular process that prepares reproductive cells?
Meiosis
When male and females reproductive cells fuse?
Fertilization
Most of the cells in an organism are called?
Diploid (two sets of chromosomes)
Somatic cells have ____ chromosomes.
46
46 chromosomes can be denoted as_____.
2n
Reproductive cells, such as gamates only have n= __ chromosomes or a haploid set.
23
An order of chromosomes pairs used to determine chromosome number and characteristics is known as.
Karotype
What are matching chromosomes pairs called?
Homologous chromosomes
Humans have 22 pairs of chromosomes that are of the same size and basic composition theses a referred to as what?
Autosome
What is the 23rd chomosomes referred to as?
Sex chromosomes
Men have __ chromosomes.
xy
Women have ___ chromosomes.
xx
Eggs and Sperm are___________.
gametes
Gametes are produced by _________.
gonads
The sequence of events that leads from one to the next is referred to as the __________.
Life cycle
Meiosis produces _____ ____, they fuse to form a ___________.
Haploid gametes
Diploid zygote
The diploid zygote undergoes ________.
Mitosis
How does meiosis divide chromosome numbers in half?
1st each chromosome is duplicated
2nd the 1st cell division occurs (meiosis I) segregating two chromosomes of a homologous pair into two haploid daughter cells ( each chromosome has two sister chromatids)
3rd, Meiosis II seprates sister chromatids, resulting in 4 haploid daughter cells (each chromosome with only 1 sister chromatid)
During meiosis diploid organisms produce ___________.
haploid gametes
During meiosis diploid organisms produce haploid gametes, it takes two divisions to do this. What are they called?
Meiosis I
Meiosis II
In contrast to mitosis,
Meiosis exchanges genetic information, allowing variation
meiosis only occurs in
overios or testes
