Significance of Mitosis and Meiosis, and Chromosomal Abnormalities from Cell Cycle

Question 1

significance of mitosis

Answer 1

• maintains the proper size of the cell (large cell - more difficult)
• maintains the genetic stability in daughter cells
  -helps repair tissue
• provides an opportunity for growth and development of a zygote

Question 2

significance of meiosis

Answer 2

• maintains a constant number of chromosomes in organisms
• provides an exchange in genes, results in genetic variation

Question 3

Identical twins

Answer 3

developed from the same egg and sperm, same sex

Question 4

fraternal twins

Answer 4

developed from 2 sets of egg and sperm, same-sex/ one of each

Question 5

incorrect number set of chromosomes

Answer 5

aneuploidy

Question 6

correct number set of chromosomes

Answer 6

euploid

Question 7

gain or has an additional chromosome

Answer 7

trisomy

Question 8

loss one chromosome

Answer 8

monosome

Question 9

the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei.

Answer 9

non disjunction

Question 10

• extra chromosome 21
• some physical characteristics include: protruding tongue, small stature, short neck, eye slanted upward

Answer 10

down syndrome/trisomy 21

Question 11

• extra X chromosome
• mostly on men
• typically have small testes
• may have low muscle tones and problems with coordination

Answer 11

Klinefelter syndrome

Question 12

• chromosome 5 is missing
• a high-pitched cry that sounds like a cat
• small head size, low birth weight, and weak muscle tone
• widely set eyes, low-set ears, small jaw, rounded face

Answer 12

cri du chat syndrome

Question 13

• a single defective gene on chromosome 4
• affects the person’s functional abilities and usually results in movement, thinking, and psychiatric disorders

Answer 13

huntington’s disease

Question 14

• all X chromosome is missing
• woman
• below average in height and experience early loss of ovarian function

Answer 14

turner’s syndrome

Question 15

why does DNA mutation change?

Answer 15

can result from errors in DNA replication during cell division, exposure to mutagens or a viral infection. radiation, diet, etc.

Question 16

occurs when the DNA sequence of an organism changes.

Answer 16

mutation

Question 17

mutations that arise when a single DNA nucleotide alteration inside a protein-coding region of a gene does not affect the amino acid sequence that makes up the gene’s protein.

Answer 17

silent mutation

Question 18

a DNA change that results in different amino acids being encoded at a particular position in the resulting protein. Some of these mutations alter the function of the resulting protein.

Answer 18

missense mutation

Question 19

a concept that helps to explain the mechanisms behind cellular aging. The concept states that a normal human cell can only replicate and divide forty to sixty times before it cannot divide anymore, and will break down by programmed cell death or apoptosis.

Answer 19

hayflick limit