Chapter 19 - DNA, Meiosis, Inheritance Flashcards Preview

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Flashcards in Chapter 19 - DNA, Meiosis, Inheritance Deck (57)
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1
Q

the building blocks within DNA

A

nucleotide

2
Q

example of a nucleotide

A

ATP

3
Q

long polymer/molecule made up of a sequence of nucleotides

A

DNA

4
Q

specific segment of DNA that determines a particular protein

A

gene

5
Q

List the nucleotide bases for proteins for DNA:

A

Adenine
Guanine
Cytosine
Thymine

6
Q

List the nucleotide bases for proteins for RNA:

A

Adenine
Guanine
Cytosine
Uracil

7
Q

What happens in the “transcription” process?

A

DNA is transcribing to RNA. The RNA is a singl stranded “copy”.

8
Q

RNA carries information out of nucleus to a ribosome, where it is translated to make a ________

A

protein

9
Q

What is the 3 base code when translating?

A

For every three nucleotides determines a particular amino acid. Language is called codons

10
Q

Long sequences of amino acid chains form ______

A

proteins

11
Q

When a DNA is essentially loose, not condensed down.

A

chromatin

12
Q

During DNA synthesis, chromatin is replicated producing what?

A

sister chromatids

13
Q

Sister chromatids are joined by a _________

A

centromere

14
Q

Attachment point for spindle fibers that pull chromatids apart during cell division

A

centromere

15
Q

Individual strands of DNA

A

chromosomes

16
Q

How many chromosomes are in a human cell? How many pairs?

A

46; 23

17
Q

Why do cells divide?

A
  1. Development and growth
  2. Replacement and repair
  3. Sex
18
Q

single cell formed by union of sperm and egg

A

zygote

19
Q

cell division that results in identical (daughter) cells

A

mitosis

20
Q

Two main phases of the cell cycle:

A
  1. Interphase

2. M-phase

21
Q

when the cell pinches off and turns into 2 new daughter cells

A

cytokinesis

22
Q

List the phases of Mitosis:

A
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
23
Q

What is the product of mitosis?

A

two genetically identical daughter cells

24
Q

a pair of chromosomes that carry the same genes, but potential different versions (alleles)

A

homologous pairs

25
Q

identical, attached copy of a chromosome

A

sister chromatids

26
Q

different versions (forms) of a specific gene

A

alleles

One copy from maternal and one copy from paternal source

27
Q

What can different alleles produce?

A

May produce the same resulting protein or different forms of a protein and different physical characteristics

28
Q

Cells that have half the number of chromosomes

A

haploid

29
Q

What is the purpose of meiosis?

A

Sex and to produce genetically different cells - male or female gametes

30
Q

If two sematic (non-sex) cells came together to form a new individual, how many chromosomes would that zygote have?

A

92

31
Q

meiosis selectively reduces the number of chromosomes in gametes by half

A

selective reduction

32
Q

to increase genetic diversity in offspring

A

genetic recombination

33
Q

Meiosis is a lot like Mitosis, but what’s the difference?

A

Meiosis has two cell divisions

34
Q

Exchange of genetic information between non-sister chromatids

A

crossing-over

35
Q

when does crossing over occur?

A

when homologous chromosomes pair with one another

36
Q

nondisjunction

A

Not come together, do not come apart

37
Q

Imbalance in chromosome number causes abnormalities in development

A

most result in miscarriage

38
Q

What causes down syndrome?

A

an extra chromosome 21

39
Q

List characteristics of down syndrome:

A

• Limits in mental development
• Abnormal skeletal growth – short stature and body parts
• Unique facial features – flatten nose, protruding tongue that forces mouth open to cause speech impediment, folded skin at corner of eyes
• Heart and digestive defects are common
• Risk of down syndrome increases with mother’s age rapidly after age 35
o By age 45 the mother is 45X more likely than at age 20

40
Q

Human chromosomes have how many genes?

A

~20,000-25,000

41
Q

Segment of DNA that codes for a particular protein

A

gene

42
Q

Human chromosomes have roughly 25,000 genes, how many proteins do they produce?

A

~100,000 proteins

43
Q

Where does mitosis occure?

A

Somatic cells/body cells (everywhere else)

44
Q

Where does Meiosis occur?

A

Only in ovaries and testes during the formation of gametes

45
Q

What is the product of Mitosis?

A

2 diploid cells

46
Q

What is the product of Meiosis?

A

4 haploid cells

47
Q

What results from Mitosis?

A

growth and repair

48
Q

What results from Meiosis?

A

gamete (egg and sperm) production

49
Q

Mitosis involves no exchange of what?

A

genetic material

50
Q

What is exchanged in Meiosis?

A

parts of chromosomes are exchanged in crossing over

51
Q

The daughter cells from Mitosis are _______ _______

A

genetically identical

52
Q

Daughter cells in Meiosis are:

A

not genetically identical

53
Q

the process of allowing too many or not enough chromosomes

A

nondisjunction

54
Q

Example of an allele

A

Hair color is determined by multiple genes

55
Q

Why are nucleotides called bases?

A

they are nitrogen containing bases

56
Q

What are made out of nucleotides?

A

DNA and nucleic acids

57
Q

List the nucleic acids

A

mRNA, rRNA, and tRNA