DNA Replication Chapter 8.1 Flashcards
Clones
genetically identical individuals from asexual reproduction (plants and fungi)
In animals 9 sponges, coral animals, hydra, and jellyfishes “bud” genetically identical clones that breakaway from the parent.
How long do new cells live for
An average of about 35 days
Purpose of cell division
produces a continuous supply of replacement cells. (cell death)
. Reproduction
. Growth and development
. Cell death
Asexual reproduction
A single cell organism( or some eukaryotes) replicates its genetic material and splitting the contents of one cell into two
. It generates genetically identical offspring
. From one parent
How do most prokaryotes reproduce
BINARY FISSION
BINARY FISSION
The simplest form of asexual reproduction usually used by bacteria and archaea
Sexual Reproduction
The production of offsprings whose genetic makeup comes from two parents.
. Each parent contribute a sex cell
. Because sexual reproduction mixes and recombines traits, the offsprings are genetically different from each other
Cell division
process by which a parent cell divides into two or more daughter cells.
3 types of cell division
- Binary fission —- prokaryote
2. Meiosis and 3. Mitosis ——Eukaryotes
2 types of cell division in Eukaryotes
- Meiosis
2. Mitosis
Meiosis
A special type of cell division necessary for sexual reproduction in eukaryotes.
.The cells produced by meiosis are gametes or spores.
. In many organisms, including all animals and land plants (but not some other groups such as fungi), gametes are called sperm and egg cells.
. meiosis produces cells that are genetically DIFFERENT from one another and the parent.
. For Reproduction
Fertilization
The union of the gametes ( sperm cell and egg cell ) to make a zygote
Zygote
the first cell of a new eukaryotic organism ( created by fertilization , when the 2 sex cell join ( sperm and egg)
What type of cell division creates gametes ( sex cells )
Meiosis (meiosis produces cells that are genetically DIFFERENT from one another and the parent.)
After fertilization and the creation of the zygote what happens
Mitosis immediately takes over
Mitosis
divides a eukaryotic cell into 2 identical daughter cells
. for growth and development
Difference between Meiosis and Mitosis
Meiosis– creates genetically different cells
Mitosis— creates genetically identically daughter cells ( similar to binary fission)
Purpose of Mitosis in Eukaryotic cells ( animals, fungi, plants)
.for growth and development
. repair damage after injury( healing)
. replace cells after they die (
Summary of cell division
That every cell in the body results from countless rounds of cell division, each time forming 2 genetically identical cells from one.
Summary of cell division and a eukaryotic life cycle
Adults produce gametes through meiosis ( sperm cell and egg). Fertilization unites the gametes creating a zygote. Mitosis immediately takes over to develop the zygote into a newborn and the newborn into an adult.
Apoptosis ( falling away from)
programmed cell death.
. disintegration of cells into membrane bound particles that eliminated by phagocytes or by shedding.
How do apoptosis and cell division work together for growth and development
. During early development they work together to shape new structures.
. They are both in balance so that tissue neither over grows or shrinks
. Cell division equally compensates for the death of a cell
. they work together to protect an organism
. healing
.
Explain the roles of mitotic cell division, meiosis, and fertilization in the human life cycle.
Mitosis allows for growth and repair from the fertilized egg to the adult.
In reproductively mature individuals, meiosis creates gametes with half the genetic material.
The male gamete then fertilizes the female gamete during sexual reproduction, forming a zygote with a full set of genetic material.
Why are both cell division and apoptosis necessary for the development of an organism?
Cell division is needed to produce the large number of cells necessary to form the individual. Combined with apoptosis, the structures in the organism can be carved out and constantly recycled.
