REVISION SHEET CORE CONCEPT
BREAKDOWN
◉ Chapter 9: Cellular Reproduction (cell cycle & DNA).
Answer: Includes: genes, chromosomes, bases, DNA, mutations,
homologous chromosomes, gametes. cell cycle interphase (G1,S,G2),
mitosis (PMAT), meiosis
◉ cellular division.
Answer: parent cell gives rise to two daughter cells
-- Each daughter cell receives a complete set of hereditary
information from the parent cell and about half its cytoplasm (info
usually identical to the hereditary info found in the parent cells)
◉ -- Cell division is required for ___ and ___
-- After cell division, the daughter cells may ___ or ____.
Answer: -- required for growth and development
-- grow and divide, or differentiate (becoming specialized for specific
functions)
◉ What is DNA?.
,Answer: Hereditary info in all cells
◉ What is DNA composed of?.
Answer: -- Nucleotides
Nucleotides composed of 1) a phosphate, 2) a sugar (deoxyribose),
and #) one of four bases - adenine (A), thymine (T), guanine (G), or
cytosine (C)
-- linked by hydrogen bonds
◉ What holds the two strands of DNA together? Explain the
structure..
Answer: -- Hydrogen bonds between complementary bases hold two
DNA strands together in a double helix, twisted, ladder-like
structure
[ The bases protrude inward toward each other from the sugar-
phosphate backbone like rungs on a ladder. Hydrogen bonds hold
the base pairs together and twisted into a double helix ]
◉ What is a chromosome?.
Answer: -- a threadlike structure of nucleic acids and protein found
in the nucleus of most living cells, carrying genetic information in
the form of genes
• Contains DNA and a protein
• Passed on during sexual reproduction
,◉ What are genes?.
Answer: -- a unit of hereditary information that is inherited from the
parent cells [and encodes information needed to produce proteins,
cells, and entire organisms]
-- sequence segments of nucleotides in DNA at specific locations on
chromosomes that contain traits passed down to offspring
◉ Inheritence.
Answer: the process by which the characteristics of individuals are
passed to their offspring
◉ How do the bases in DNA pair?.
Answer: A-T and C-G
◉ What is the cell cycle?.
Answer: The repeating pattern of divide, grow, and differentiate,
then divide again in cells
◉ What is the order of the phases in the cell cycle?.
Answer: • Interphase- G1, S, then G2 (cell growth, DNA
synthesis/replication, differentiates)
• Prophase- chromatin condense and nucleolus disappears
, • Metaphase- chromosomes line up in the middle of the cell
• Anaphase- paired chromosome separate and begin moving to
opposite sides of the cell
• Telophase- cell splits in two
• Cytokinesis- cytoplasm divides
◉ What occurs during interphase?.
Answer: A cell grows in size, replicates DNA, and differentiates
◉ What occurs during prophase?.
Answer: The chromosomes condense, the spindles form, and the
chromosomes are captured by the spindles
◉ What occurs during metaphase?.
Answer: The chromosomes line up along the equator of the cell
◉ What occurs during anaphase?.
Answer: Sister chromatids separate and are pulled to opposite poles
of the cell
◉ What occurs during telophase?.
Answer: Nuclear envelopes form around both groups of
chromosomes and the cytoplasm is split (cytokinesis)