Chapter 3 Flashcards
How do Unicellular organisms reproduce
through cell division.
When does most growth in multicellular organisms occur
when cells dividing produce new cells.
How do multicellular organisms reproduce?
cell division is involved in growth, development, and reproduction.
The genetic material of eukaryotic cells is organized in
chromosomes
The genetic material of a cell contains information needed for
the cell’s growth and other activities
What happens When a cell divides into two new cells,
each new cell receives a full set of genetic material
The genetic material in cells is contained where?
in DNA molecules
What is DNA
deoxyribonucleic acid
It is the genetic material in cells.
And is a chemical that contains information for an organism’s growth and functions.
James Watson and Francis Crick showed that DNA is made of what?
two strands of molecules joined in a structure that resembles a twisted ladder or a double helix.
In a eukaryotic cell, where is most of the cells DNA found?
in the nucleus and exists as a mass of loose strands.
DNA is wrapped around what?
proteins like threads that wrap around a spool and compacted into structures called chromosomes.
During division, a duplicated chromosome can be seen as two identical structures called
chromatids that are held together by a centromere
Humans have how many chromosomes,
46
fruit flies has how many chromosomes
8
corn plants has how many chromosome
20
What happens When an organism ages or is injured?
the worn-out or damaged cells are replaced by new cells forming from healthy cells dividing
What is the limits to the size that cells can reach.
It’s related to the control of cell division.
When the cell divide into two smaller cells, the ratio of surface area to volume for each cell increases.
What happens through cell division and development?
cells become specialized to perform particular functions.
The body repairs injuries by means of
cell division
The human body is made up of about how many different types of cells
200
What is a cycle?
A cycle is an activity or set of event that regularly repeats.
The cell cycle includes what?
interphase and cell division.
Life cycle
The process in which All living things live, grow, reproduce and die
cell cycle
the normal sequence of development and division of a cell.
What are The cell cycle two main phases
1- interphase- in which the cell carries out its functions,
2- the cell divides, which can include mitosis and cytokinesis.
eukaryotes undergo what?
mitosis
Interphase
The part of the cell cycle during which a cell is not dividing.
What activities takes place During interphase,
the cell grows to about twice the size
The cell transports materials in and transporting wastes out.
Also, cellular respiration occurs, which provides the energy the cell needs.
Before a cell can divide what must occur
The cell must duplicates its DNA exactly to ensures that, after cell division, each new cell gets a complete set of DNA.
Mitosis
is the part of the cell cycle during which the nucleus divides.
Why don’t Prokaryotes do not undergo mitosis
because they have no nucleus.
What Is The function of mitosis
to move the DNA and other material in the parent cell into position for cell division.
Cytokinesis
the division of the parent cell’s cytoplasm, and occurs immediately after mitosis.
Daughter cell
A result of mitosis and cytokinesis, the original cell splits into two genetically identical daughter
Each daughter cell receives a complete set of DNA from the parent cell.
What do new cells do?
New cells help your body grow, develop, repair itself and replace worn-out parts.
Mitosis has how many phases
4
Phase 1. Chromosomes form.
the DNA in the nucleus of a cell condenses and becomes visible under a light microscope. Each chromosome consists of two identical chromatids held together by a centromere. The membrane around the nucleus disappears.
Phase 2 metaphase
The chromosomes line up in the middle of the cell.
Phase 3- anaphase
Chromosomes separate. the chromatids split, resulting in two separate identical chromosomes. These chromosomes are pulled to opposite sides of the cell.
Phase 4 telophase
A new nuclear membrane forms around each group of chromosomes. The chromosomes return to their threadlike form.
the parent cell’s cytoplasm is divided to complete the parent cell’s division into two entirely separate daughter cells.
What is Cytokinesis
the division of the parent cell’s cytoplasm, Cytokinesis differs slightly in animal cells and plant cells.
What happens during cytokinesis in an animal cell?
the cell wall prevents the cell membrane from being pulled inward. A structure called a cell plate grows between the two nuclei. The cell plate develops into a membrane an eventually becomes part of the new cells. Forming 2 completely separate daughter cells
