Genetics

Question 1

Mitosis

Answer 1

Creates two diploid cells

G1: rapid growth and cell activity
S: DNA synthesis
G2: cell prepares for division
M: mitosis
C: cytokinesis

Question 2

Mitotic phase

Answer 2

Prophase: chromosomes coil up and take shape, centrioles move to opposite poles and send out microtubules
Metaphase: chromosomes align themselves along the equatorial plate of the cell
Anaphase: chromosomes split at the centromere and separate (spindle fibers contract) to opposite poles
Telophase: chromosomes start to uncoil and decondense, cleavage furrow forms near center of the cell, one cell becomes two
Cytokinesis: cell membrane moves inward to create two daughter cells with identical chromosomes in their nucleus

Question 3

Karyotype

Answer 3

Look at all of your chromosomes

Question 4

Meiosis

Answer 4

Creates four haploid cells, just mitosis twice

Question 5

Gametogenesis

Answer 5

production of sex cells through meiosis

Question 6

Spermatogenesis

Answer 6

-Meiosis in males
-250 million sperm a day
-occurs from puberty to death

Question 7

Oogenesis

Answer 7

-meiosis in females
-starts before birth but pauses in meiosis 1 before the cells divide and resumes in puberty
-produces one egg and three polar bodies to support a zygote after fertilization

Question 8

Congenital disorders

Answer 8

-clinical problems visible at birth are congenital defects
-they are caused by mutations in genes or environmental agents (alcohol abuse, viruses e.g. measles)

Question 9

Nondisjunction

Answer 9

failure of chromosomes or tetrads to separate properly during anaphase

Question 10

Down syndrome

Answer 10

3 copies of chromosome 21

Question 11

Klinefelters syndrome

Answer 11

Infertile male XXY

Question 12

Triple x

Answer 12

Infertile female XXX

Question 13

Jacobs syndrome

Answer 13

Masculine and steric XYY

Question 14

Turners syndrome

Answer 14

Underdeveloped female X

Question 15

Gregor Mendel

Answer 15

Used pea plants to study genetics, heredity, and variation

Question 16

Anton Van Leewenhoek

Answer 16

Believed that there were miniature people in sperm

Question 17

19th century British theory

Answer 17

red plant + white plant = pink plant

Question 18

Charles Darwin

Answer 18

offspring have variations of parental characteristics

Question 19

Law of independent assortment

Answer 19

alleles of different genes assort independently of each other during gamete formation, so different traits are inherited independently of each other

Question 20

Law of segregation

Answer 20

hen any individual produces gametes, the copies of a gene separate so that each gamete receives only one copy of a gene and therefore only one allele for all possible traits

Question 21

Ideal ratio of alleles

Answer 21

9:3:3:1

Question 22

Incomplete dominance

Answer 22

either trait is dominant or recessive, a heterozygous individual is a blend of both traits
eg. red + white = pink

Question 23

Codominance

Answer 23

both phenotypes are expressed
eg. spotted cow

Question 24

Sickle cell anemia

Answer 24

-decrease the ability of red blood cells to carry oxygen throughout the body.
-Blood cells become hard and irregularly shaped, they get clogged in small vessels and do not deliver oxygen to tissues.
-These people are immune to malaria

Question 25

Type O blood

Answer 25

universal donor because it has no antigens

Question 26

Type A, B and AB

Answer 26

have antigens for themselves

Question 27

Hemophilia

Answer 27

condition that affects the body's ability to produce proteins that clot blood. (x-linked recessive)

Question 28

X-linked diseases

Answer 28

red-green colorblindness, hemophilia, x-linked severe combined immunodeficiency

Question 29

Barr bodies

Answer 29

-inactive X chromosome -in females only one X chromosome is functioning

Question 30

Autosomal

Answer 30

-not x or y linked - eg. albinism, tay sachs, cystic fibrosis

Question 31

PCR

Answer 31

Polymerase chain reaction: an enzyme that copies DNA (archaea). It moves along the DNA and creates complementary nucleotides. used for fingerprinting

Question 32

Gel electrophoresis

Answer 32

clear jello with pores that DNA travels through towards the positive end to separate the sizes of DNA

Question 33

Friedrich Miescher

Answer 33

isolated nuclein (RNA and DNA) from nucleus

Question 34

Phoebe Levine

Answer 34

identified four bases of DNA

Question 35

Linus Pauling

Answer 35

chromosomes were hereditary material

Question 36

Frederick Griffith

Answer 36

experiments on pneumonia by heat-treating and killed them

Question 37

Oswald Avery

Answer 37

discovered nucleic acids exchanging

Question 38

Chargaffs Rule

Answer 38

always have Adenine and Thymine at the same ratio, and Cytosine and Guanine

Question 39

Rosalind Franklin

Answer 39

x-ray crystallography, photographed first double helix

Question 40

James Watson and Francis Crick

Answer 40

Stole Franklins photo

Question 41

RNA

Answer 41

has uracil and adenine (instead of thymine)

Question 42

Nitrogenous bases

Answer 42

Pyrimidines: cytosine, uracil, thymine Purines: adenine, guanine

Question 43

DNA vs RNA

Answer 43

DNA has one more oxygen

Question 44

Nucleotide contains

Answer 44

-phosphate group -5-carbon sugar (ribose and deoxyribose) -nitrogenous base (pyrimidines and purines)

Question 45

Structure of DNA

Answer 45

Backbone: phosphates and deoxyribose sugar Teeth: nitrogenous bases

Question 46

Thymine and cytosine

Answer 46

-one ring of carbon and nitrogen atoms -TWO HYDROGEN BONDS

Question 47

Adenosine Triphosphate

Answer 47

what the mitochondria makes

Question 48

Adenine and guanine

Answer 48

-two rings of carbon and nitrogen atoms (guanine GOT the oxygen) -THREE HYDROGEN BONDS

Question 49

Types of chromosomal mutations

Answer 49

1. Deletion (missing a section) 2. Duplication (copy a section twice) 3. Inversion (DNA put back in backwards) 4. Translocation (moved to different spot on chromosome) 5. Nondisjunction

Question 50

Point mutation

Answer 50

Affects a single base pair by substitution from another 1. Nonsense mutations: code for a stop that can translate the protein 2. Missense mutations: code for a different amino acid 3. Silent mutations: code for the same amino acid

Question 51

Frameshift mutation

Answer 51

Entire code shifts forward or backward. (genes are read in threes) 1. Insert a new nucleotide into the chain 2. Remove one nucleotide into the chain (forwards)

Question 52

Causes of mutations

Answer 52

Physical: radiation from UV rays, x-rays, or extreme heat Chemical: molecules misplace base pairs or disrupt helical shape of DNA, drugs