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Flashcards in Lecture 1 Deck (72):
1

Molecular genetics def'n

Field of bio that studies the structure and function of genes at a molecular level

2

Albinism results from a defect in genes involved in which of following?

a. Hair color determination
b. Skin formation
c. Keratin productions
d. Melanin production

d.

3

T/F: If a gene is recessive it may be inherited from one parent for the phenotype to be expressed.

False, defective gene must be inherited from each parent.

4

What may be the reason that there is a high freq of albinism in Hopi Native Americans?

Cultural practices:

This tribe believes albinos to be blessed, so they are treated with great admiration and respect.

Seen as "high" members in tribe hierarchy

5

When does a normal cell convert to a cancer cell?

When an oncogene mutates and becomes inappropriately activated.

6

Which of the following is most true about the relationship btw diseases and genes?

a. Defective genes always cause disease
b. Genes have no effect on cause or prevention of diseases
c. Genes affect our susceptibility to many diseases and disorders
d. Environmental circumstances has no effect on disease onset

c.

7

What is advantage of using BabyGenes?

Screen for mutations not on most newborn screening panels

If find disorder, can intervene to improve quality of life for baby

8

Three aspects of regulation that genes must do correctly to be effective

Must regulate/control correct Mechanism
In correct Space/Area
At correct Time

9

Genome def'n

A complete set of genetic instructions for any organism

10

T/F: Coding system for genomic information is very different among organisms

False, coding system for genomic info is VERY SIMILAR among organisms

11

Transmission Genetics/Classical genetics def'n

How traits are passed from one generation to the next

12

Molecular genetics

Gene structure, function and regulation

13

Population genetics

Study of the genetic composition of groups (populations) and how gene freq changes geographically over time - essentially study of evolution

14

Model genetic organisms

Organisms w/ characteristics that make them useful for genetic analysis

15

Six most extensively used model organisms in genetics:

Fruit fly
E. coli
C. elegans
Arabidopsis
Mus musculus
Yeast

16

6 Common characteristics of model organisms

Short generation time
Many offspring
Ability to carry out controlled genetic crosses
Ability to be reared in a lab environ.
Accumulated body of knowledge about organism's genetic system

17

Why are animal model organisms valuable?

Similarity among all living things

18

Drosphila (fruit flies) have been very useful in studying what?

Regulation of development, specifically Wnt genes, HOX genes, and Notch genes

19

What does the fact that HOX (homeobox) genes has remained unchanged over millions of yrs of evolution tell us?

HOX genes play a vital role in the general organization of the body in almost all organisms

20

What was first multicellular organism to have its whole genome sequenced?

C. elegans

21

Which model organism has served as one of the foundations for perfecting the genetic modification of food for cultivation and human consumption?

Arabidopsis

22

Which model organism is a primitive eukaryote but still has the basic genetic make-up that humans do?

Yeast

23

Why are zebrafish a good model organism?

Fertilized egg to adult in ~13 days

Bodies are transparent up until day 12, so can modify a gene and see how organs are developing

24

What are some of the implications of all organisms having similar genetic systems?

a. That all life forms are genetically related
b. That research findings on one organism's gene function can often be applied to other organisms
c. That genes from one organism can often exist and thrive in another organism
d. All of the above

d.

25

Performationism

Incorrect

Miniature organism resides in sex cells (sperm) and miniature organism grows over time

All traits inherited from male parent (sperm)

26

Blending of inheritance

Incorrect

Genes blend/mix and are determined from a range bound by traits found in parents

27

According to blending of inheritance what should the height of a child born to one tall and one short parent be?

Height btw that of two parents

28

Problems with blending of inheritance theory

Don't always get intermediate when mix two extremes

When get intermediate, how do you then get the extremes back

Offspring can be taller than parents

29

Inheritance of acquired characteristics

Incorrect

Acquired traits become incorporated into hereditary info

30

Lamarckianism

Theory under umbrella of Inheritance of acquired characteristics

If an organism changes during its life in order to adapt to its environment, those changes are passed onto offspring

31

Lamarck's theory of giraffe evolution

Original short-necked ancestors stretched necks to grab food causing necks to grow incrementally and the resulting growth of neck was passed onto offspring.

As generations passed ever longer necks passed on

32

Pangenesis

Incorrect

Genetic info travels from diff parts of the body to reproductive organs and packaged into sperm/egg and then passed on to resulting embryo

33

Germ-plasm theory

Correct

All cells contain complete set of genetic info
- Germ cells contain and transmit heritable info
- Somatic cells contain genetics info to carry out bodily functions but do not transmit hereditary info

34

Cell theory

Correct

All life composed of cells, and cells only arise from other cells

35

Mendelian inheritance

Correct

Traits are inherited in accord with defined principles

36

Genetics def'n

Study of genes, heredity, and genetic variation in living organisms

37

Main differences between Prok and Euk?

Prok - unicellular, Nucleus absent, smaller, circular DNA, small amount of DNA, eubacteria no histones/some archaea histones, no membrane bound organelles
Euk - unicellular or multicellular, Nucleus present, larger, chromosomes, histones, large amount of DNA, membrane bound organelles

38

Viruses differences

Neither Prok or euk

Outer protein coat surrounding nucleic acid

39

Similarities between Prok and Euk cell reproduction

Reproduce perfect copy of parent's genome

High rate of replication

40

Diploid cells

Carry two sets of genetic info organized as homologous pairs

N=23
23 pairs = 2n = 46 chromosomes total

Examples: Zygotes and somatic cells

41

Haploid cells

Carry one set of genetic info

1n = 23 chromosomes

Examples: Gametes

42

Homologous chromosomes

Similar but NOT identical

Each homologous chromosome carries same genes in same order, but the alleles for trait may not be the same

43

Staining of chromosomes

Each chromosome has DNA seq unique to that chromosome

Allow staining unique to each chromosome

Can be used in treatment of disease

44

Diploid cells have:

A. Two chromosomes
B. Two sets of chromosomes
C. One set of chromosomes
D. Two pairs of homologous chromosomes

D.

45

Centromere

Attachment point for spindle fibers/microtubules

Where kinetochores form

46

Telomeres

Unique DNA seq/proteins that form the stable tip/cap of a linear chromsome

47

Function of Telomeres

Linear chromosomes have exposed ends that can be easily damaged

Telomeres protect chromosomes from this damage

48

Origins of replication

Where DNA synthesis begins

Unique DNA seq/proteins that allow for replication of the chromosome to begin

49

Does circular DNA have telomeres?

No

50

Can the telomeres be easily replicated?

No

51

Interphase

An extended period btw cell divisions: G1, S, and G2 phases

DNA synthesis
Chromosomal replication
Cell growth

52

Phase check points

Key transition points

53

M phase

Mitotic phase - nuclear and cellular division

Mitosis and cytokinesis

54

G1 phase

Cell growth
Proteins necessary for cell division synthesized

55

G1/S checkpoint

Regulated decision point

After pass this cell is committed to dividing

56

G0

Non-dividing phase

57

When is the cell committed to dividing?

After G1/S checkpoint

58

S phase

DNA synthesis and replication

59

G2

Cell prepares biochemically for mitosis

60

G2/M checkpoint

Only passed if DNA is completely replicated and undamaged after which cell can divide

61

Order of phases/checkpoints of cell cycle

G1, G1/S checkpt, S, G2, G2/M checkpt, Mitosis, Spindle-assembly checkpt, cytokinesis

62

Mitosis (in general)

Separation of sister chromatids

63

Cytokinesis

Separation of cytoplasm

64

Phases of mitosis

Prophase
Prometaphase
Metaphase
Anaphase
Telophase

65

Prophase

Chromosomes condense
Chromosomes = Two sister chromatids
Mitotic spindle/centrosomes form

66

Prometaphase

Nuclear membrane disintegrates
Spindle microtubules attach to chromatids

67

Metaphase

Chromosomes line up along metaphase plate

68

Anaphase

Sister chromatids separate and toward oppo poles

69

Telophase

Chromosomes arrive at poles
Nuclear membrane reforms
Chromosomes relax
Cell divides

70

Genetic consequences of cell cycle

Produces two cells that are genetically identical (but not always) w/ cell that gave rise to them

Have a full complement of chromosomes

Each daughter cells have half the cytoplasm and organelle content of parent cell

71

Why are the daughter cells resulting from mitosis NOT always identical to parent cell

Mutations
Crossing over

72

Which is correct order of stages of cell cycle?

A. G1, S, metaphase, anaphase
B. S, G1, metaphase, anaphase
C. prophase, S, G1, metaphase, anaphase
D. S, G1, anaphase, prophase, metaphase

A