Midterm Review

Question 1

During which phase of the cell cycle does the cell carry out its normal functions?

Answer 1

Growth 1

Question 2

During which phase of the cell cycle does the DNA replicate and why is it before the cell divides?

Answer 2

S phase - before the cell divides so that the new cells have an exact complete set of chromosomes

Question 3

What is the role of cyclins and kinases in the cell?

Answer 3

Control the cell

Question 4

What happens in the G2 phase of the cell cycle?

Answer 4

Final growth and critical checkpoints before mitosis

Question 5

What are the steps of mitosis in the correct order?

Answer 5

Prophase, Metaphase, Anaphase, Telophase

Question 6

When in the cell cycle does the cytoplasm divide (what phase does it follow)?

Answer 6

Follows Telophase

Question 7

What is the division of the cytoplasm called?

Answer 7

Cytokinesis

Question 8

What is the difference between diploid and haploid cells?

Answer 8

Haploid- 1 set of chromosomes, ex. include reproductive cells and gametes
Diploid- 2 sets of chromosomes, ex. include somatic/body cells

Question 9

How many chromosome are found in human body cells?

Answer 9

46

Question 10

When does crossing over take place?

Answer 10

Meiosis 1 (Prophase 1- when homologous chromosomes line up)

Question 11

How does meiosis/crossing over help with the continuation of a species?

Answer 11

Provides genetic variation

Question 12

Describe the process of Meiosis’s first phases of PMAT

Answer 12

Prophase 1- homologous chromosomes appear and crossing over occurs (leads to variation)
Metaphase 1- homologous chromosomes line up along the middle of the spindle
Anaphase 1- Homologous chromosomes separate and are pulled to opposite ends of the cell
Telophase 1- Spindle fibers disassemble and cell undergoes cytokineses and is ready for PMAT 2

Question 13

Describe the process of meiosis 1

Answer 13

Division of homologous chromosomes

Question 14

Describe the process of meiosis 2

Answer 14

Sister chromatids are divided to make four haploid cells

Question 15

What is cancer?

Answer 15

Uncontrolled cell growth

Question 16

What effect do cancer cells have on other healthy cells?

Answer 16

Cancer cells deprive health cells of nutrients

Question 17

What is the difference between a malignant and benign tumor?

Answer 17

Benign- doesn’t move

Malignant- moves to other parts of the body

Question 18

What are stem cells?

Answer 18

Unspecialized cells that have not yet differentiated

Question 19

What is/results from nondisjunction?

Answer 19

Failure of the chromosomes to separate correctly thus resulting in too many or too few chromosomes

Question 20

What is a photo of an organism’s chromosomes called?

Answer 20

Karyotype

Question 21

Who was the father of genetics?

Answer 21

Mendel

Question 22

What are Mendel’s three laws?

Answer 22

1. Law of Dominance- dominant allele is expressed when it is present
2. Law of Independent Assortment- Allele pairs separate independently of each other during gamete formation
3. Law of Segregation- organism inherits 2 copies of each gene, one from each parent. Organisms can only donate one copy of each gene in their gametes

Question 23

Which of Mendel’s Laws is an explanation of the variation between species?

Answer 23

Law of Independent Assortment

Question 24

Which of Mendel’s Laws states that organism inherit two copies of each gene, one from each parent?

Answer 24

Law of Segregation

Question 25

What is the genotype of a person with a recessive disorder?

Answer 25

Homozygous Recessive

Question 26

What do you call a distinguishing characteristic that can be inherited?

Answer 26

Trait

Question 27

What is the difference between dominant and recessive traits?

Answer 27

Dominant- expressed if present in genotype | Recessive- only seen if a dominant allele is not present to mask it

Question 28

What chromosomes determine the sex of the offspring?

Answer 28

Sex Chromosomes

Question 29

What is the sex of a human with chromosomes "XX"?

Answer 29

Female

Question 30

What is the sex of a human with chromosomes "XY"?

Answer 30

Male

Question 31

With X-linked traits (such as colorblindness) why are males more often colorblind compared to females?

Answer 31

They only have one X chromosome

Question 32

What is the process that produces an exact copy of DNA?

Answer 32

Replication

Question 33

During which phase of the cell cycle does the DNA replicate?

Answer 33

Synthesis

Question 34

What does semi-conservative mean?

Answer 34

Gives a copy- not original, translates to mRNA

Question 35

What do we call organisms that have altered genes or genomes

Answer 35

Genetically Engineered

Question 36

Which scientists discovered the shape and built a model of DNA?

Answer 36

Watson and Crick

Question 37

What is the shape of DNA?

Answer 37

Double Helix/Twisted Ladder

Question 38

What are the base pairing rules for DNA?

Answer 38

A -> T | C -> G

Question 39

What is transcription?

Answer 39

DNA is converted into mRNA

Question 40

Which enzyme builds and "proof reads" DNA while replicating?

Answer 40

DNA Polymers

Question 41

What does the central dogma state?

Answer 41

DNA -> RNA -> Protein

Question 42

What are the three letter sequences in RNA called?

Answer 42

Codon

Question 43

What is a point mutation or a substitution?

Answer 43

Only one base is incorrect

Question 44

What is frame-shift mutation?

Answer 44

Base is either inserted or deleted (most destructive)

Question 45

Where in the eukaryotic cell is the DNA located?

Answer 45

Nucleus

Question 46

What is DNA composed of?

Answer 46

Nucleotides

Question 47

What is the difference between the three types of RNA?

Answer 47

1. mRNA- carries message or instructions that will be changed into amino acids 2. tRNA- carries/transfers amino acids to ribosomes 3. rRNA- located in ribosomes & does the building

Question 48

What is the sequence of the entire DNA in an organism (every chromosome)?

Answer 48

Genome