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Notes Cell Cycle
Chapter 2.3
Pages 48-51
Life Cycle of a Cell
• Cell Cycle: Eukaryotes (with nucleus)
– Interphase – Growth phase
– Mitosis – Cell separates DNA
– Cytokenesis – Cell divides into two
identical cells.
• Cell Cycle: Prokaryotes (no nucleus)
– Interphase
– Binary Fission
Prokaryotic DNA
• Instead of chromosomes the DNA is
arranged into a ________
that is attached to
circle.
the _______________.
cell membrane.
Binary Fission
• Binary Fission means:
Splitting in two!
Eukaryotic DNA
• What it does:
Is the instructions or blueprint for all cell
activities.
• How it is organized:
DNA is wrapped with
proteins to create thick
structures called
chromosomes.
Chromosomes
• Chromosomes:
DNA wrapped with proteins to create thick
structures that are visible with a microscope.
• Number of chromosomes:
Each organism has a different number of
chromosomes.
• Homologous Chromosomes:
You have two copies of each chromosome (1
from mom & 1 from dad). This pairs have the
same type of information.
Interphase
• The cell grows.
– Makes copies of organelles.
– Makes a copy of chromosomes.
• Copied Chromosomes are called:
Chromatid pairs or sister
chromatids
Mitosis
• Has four stages:
– Prophase
– Metaphase
– Anaphase
– Telophase
Cytokinesis
• In Animal cells: (no cell wall)
The cell membrane pinches in toward the
middle until the two sides meet.
• In plant cells: (with a cell wall)
A cell plate forms in the
middle and grows outward
until it reaches the cell wall.