Chapter 5 Biology The Core
Cell Theory states that all life is cellular, and that all cells arise from preexisting cells
Cell Division the two offspring cells are genetically identical to each other and to the original
parent cell
Sexual Reproduction formation of genetically unique offspring
Fertilization joining of gametes to form a single cell called the zygote
Zygote fertilized egg
Gametes Egg and sperm cells are formed via cell division from adult cells in the gonads
Development Through repeated rounds of cell division, the single cells of the zygote develops into
an embryo, then a fetus, then a baby, and finally an adult.
Growth and Repair As a body grows from a baby to an adult, cell division, provides new cells needed to
expand tissues and organs. In an adult, millions of cells divide every second to
replace lost or damaged cells-- to heal a wound, for example.
Asexual Reproduction the creation of a new individual by a lone parent without participation of sperm and
egg.
Binary Fission Single-Celled organisms can reproduce asexually by binary fission (splitting into
two). In binary fission, an organism's single divides, creating two genetically
identical offspring.
Plant Reproduction Most plants reproduce sexually, but many plants can also reproduce themselves
asexually by sprouting (such as the eyes of potatoes) or by sending out runners.
Humans take advantage of this ability by removing cuttings and using them to grow
new plants.
Regeneration Some animals can regenerate lost limbs, and some of them (such as the sea star)
can even regenerate an entire body starting from a severed limb.
5.1 Core Idea (Cell division provides for reproduction, Cell division - the formation of cells from preexisting - underlies many important
growth, and repair) biological possesses, including the formation of gametes, the development of an
adult from an embryo, the growth and repair of bodily tissues, and asexual
reproduction.
From a cell division perspective, why are all of the trillions Because they all descended via cell division from a single original cell (the zygote).
of cells in your body genetically identical?
DNA genetic material
, Chapter 5 Biology The Core
Genes units of inheritance made from DNA that code for proteins
Chromosomes a gene carrying structure found in the nucleus of a eukaryotic cell and most visible
during mitosis and meiosis; also, the main gene-carrying structure of a prokaryotic
cell. Each chromosome consists of one very long threadlike DNA molecule and
associated proteins.
Chromatin the DNA and the protein form a package called the
Sister Chromatids as a cell prepares to divide, it replicates its chromosomes and then compacts them
into a dense pair called
Centromere Sister chromatids are held together by this
5.2 Core Idea (Chromosomes are association of DNA and Every eukaryotic cell contains chromosomes in the nucleus. Each chromosome
protein) consists of one long piece of DNA associated with proteins that help to compact and
organize it. Together, the DNA and protein form chromatin.
How many individual pieces of DNA are in the nucleus of Forty-six, one long piece of DNA for each chromosome.
each of your body cells?
Cell Cycle an ordered sequence of events from the time a cell is created from a dividing parent
cell until its own division into two cells
Interphase the cell performs its normal functions and duplicates the chromosomes
Mitotic phase the cell divides the nucleus and distributes the duplicated chromosomes into two
new cells.
Mitosis the nucleus divides and is distributed to the two offspring cells
Cytokinesis the cytoplasm is divided and distributed
5.3 Core Idea (Cells have regular cycles of growth and The cell cycle is an ordered sequence of events that leads from the creation of a
division) cell to the division of that cell. The cell cycle can be divided into two broad phases:
interphase (during which the cell grows, duplicates its chromosomes, and prepares
for division) and the mitotic phase (which includes mitosis and cytokinesis)
Explain why the following statement is incorrect: "During Because the chromosomes are already duplicated (during interphase) by the time
mitosis, chromosomes are duplicated and distributed." the mitotic phase starts.
Mitotic Spindle protein tracks that the cell lays down so the chromosomes can be organized.
Cell Theory states that all life is cellular, and that all cells arise from preexisting cells
Cell Division the two offspring cells are genetically identical to each other and to the original
parent cell
Sexual Reproduction formation of genetically unique offspring
Fertilization joining of gametes to form a single cell called the zygote
Zygote fertilized egg
Gametes Egg and sperm cells are formed via cell division from adult cells in the gonads
Development Through repeated rounds of cell division, the single cells of the zygote develops into
an embryo, then a fetus, then a baby, and finally an adult.
Growth and Repair As a body grows from a baby to an adult, cell division, provides new cells needed to
expand tissues and organs. In an adult, millions of cells divide every second to
replace lost or damaged cells-- to heal a wound, for example.
Asexual Reproduction the creation of a new individual by a lone parent without participation of sperm and
egg.
Binary Fission Single-Celled organisms can reproduce asexually by binary fission (splitting into
two). In binary fission, an organism's single divides, creating two genetically
identical offspring.
Plant Reproduction Most plants reproduce sexually, but many plants can also reproduce themselves
asexually by sprouting (such as the eyes of potatoes) or by sending out runners.
Humans take advantage of this ability by removing cuttings and using them to grow
new plants.
Regeneration Some animals can regenerate lost limbs, and some of them (such as the sea star)
can even regenerate an entire body starting from a severed limb.
5.1 Core Idea (Cell division provides for reproduction, Cell division - the formation of cells from preexisting - underlies many important
growth, and repair) biological possesses, including the formation of gametes, the development of an
adult from an embryo, the growth and repair of bodily tissues, and asexual
reproduction.
From a cell division perspective, why are all of the trillions Because they all descended via cell division from a single original cell (the zygote).
of cells in your body genetically identical?
DNA genetic material
, Chapter 5 Biology The Core
Genes units of inheritance made from DNA that code for proteins
Chromosomes a gene carrying structure found in the nucleus of a eukaryotic cell and most visible
during mitosis and meiosis; also, the main gene-carrying structure of a prokaryotic
cell. Each chromosome consists of one very long threadlike DNA molecule and
associated proteins.
Chromatin the DNA and the protein form a package called the
Sister Chromatids as a cell prepares to divide, it replicates its chromosomes and then compacts them
into a dense pair called
Centromere Sister chromatids are held together by this
5.2 Core Idea (Chromosomes are association of DNA and Every eukaryotic cell contains chromosomes in the nucleus. Each chromosome
protein) consists of one long piece of DNA associated with proteins that help to compact and
organize it. Together, the DNA and protein form chromatin.
How many individual pieces of DNA are in the nucleus of Forty-six, one long piece of DNA for each chromosome.
each of your body cells?
Cell Cycle an ordered sequence of events from the time a cell is created from a dividing parent
cell until its own division into two cells
Interphase the cell performs its normal functions and duplicates the chromosomes
Mitotic phase the cell divides the nucleus and distributes the duplicated chromosomes into two
new cells.
Mitosis the nucleus divides and is distributed to the two offspring cells
Cytokinesis the cytoplasm is divided and distributed
5.3 Core Idea (Cells have regular cycles of growth and The cell cycle is an ordered sequence of events that leads from the creation of a
division) cell to the division of that cell. The cell cycle can be divided into two broad phases:
interphase (during which the cell grows, duplicates its chromosomes, and prepares
for division) and the mitotic phase (which includes mitosis and cytokinesis)
Explain why the following statement is incorrect: "During Because the chromosomes are already duplicated (during interphase) by the time
mitosis, chromosomes are duplicated and distributed." the mitotic phase starts.
Mitotic Spindle protein tracks that the cell lays down so the chromosomes can be organized.
