Chapter 3

Question 1

What are the fundamental units of life in all organisms?

Answer 1

cells

Question 2

what type of cells on earth began life?

Answer 2

sukaroyotic cells

Question 3

these cells are three dimensional structures composed of carbohydrates, lipids, nucleic acid, proteins, and substructures called organelles

Answer 3

sukaroyotic cells

Question 4

What is a nucleus?

Answer 4

a part of cell surrounded by cytoplasm, (which breaks down nutrients and converts them to other substances to store energy through protein synthesis), a nucleus contains DNA and RNA

Question 5

What do mitochondria do?

Answer 5

produce energy within a cell

Question 6

What do ribosomes do?

Answer 6

assist in protein synthesis

Question 7

what are somatic cells?

Answer 7

they are cells composed of body cells

Question 8

what are gametes?

Answer 8

reproductive cells

Question 9

What are the three most important aspects of DNA code?

Answer 9

The code is triplet, the code is continuous ,the code is redundant, the code is universal

Question 10

What did Crick and watson do?

Answer 10

find DNA in 1953

Question 11

DNA is composed of what?

Answer 11

two chains of small units called nucleotides- these are made up of a sugar molecule, a phosphate group, and one nitrogenous base.

Question 12

What are the four bases of the double helix in DNA?

Answer 12

adenine, guanine, thymine, and cytosine- this allows for DNA to replicate

Question 13

DNA replication happens when?

Answer 13

When a cell divides and enzymes break the bond between bases through DNA, attraction occurs in a complimentary way (A’s only to T’s etc)

Question 14

What is the assembly of protein in a cell called?

Answer 14

protein synthesis

Question 15

Where does protein synthesis take place?

Answer 15

outside the cell nucleus,

Question 16

What do enzymes do?

Answer 16

regulate chemical reactions

Question 17

What is RNA also called?

Answer 17

messenger DNA

Question 18

What are the 3 important aspects of RNA?

Answer 18

1. Single Stranded, 2. contains a different type of sugar 3. contains the base uracil as a substitute for the DNA base thymine

Question 19

What are mRNA triplets called?

Answer 19

condons

Question 20

What does mRNA do?

Answer 20

transfers RNA (tRNA) to the ribosome

Question 21

What do ribosomes do?

Answer 21

join everything within the cell together

Question 22

What is a gene?

Answer 22

a sequence of DNA bases that specifies the order of amino acids in an entire protein, a portion, or any functional product (i.e. RNA). A gene made be made up of hundreds or thousands of DNA bases organized into coding and non-coding segments.

Question 23

Genome

Answer 23

the entire genetic makeup of an individual or species

Question 24

how many DNA bases do humans have?

Answer 24

3 billion

Question 25

Exons

Answer 25

segments of genes that are transcribed and are involved in protein synthesis

Question 26

Introns

Answer 26

segments of genes that are initially transcribed and then deleted. Are not involved in protein synthesis

Question 27

Regulatory Genes

Answer 27

Genes that influence the activity of other genes

Question 28

Why are regulatory genes important to evolution?

Answer 28

direct embryonic development and are involved in many processes throughout life

Question 29

homeobox genes

Answer 29

an evoutionarily ancient family of regulatory genes that direct the development of the overall body plan and segmentation of body tissues

Question 30

what are responsible for various physiological differences between closely related species or different breeds of domesticated animals?

Answer 30

homeobox genes

Question 31

What does sickle-cell anemia result from?

Answer 31

a defective beta chain

Question 32

What is a point mutation?

Answer 32

a change in one of the 4 DNA bases

Question 33

Chromosomes

Answer 33

consist of DNA and protein, humans have 46, chimps have 48

Question 34

Two types of chromosomes:

Answer 34

autosomes- all chromosomes except sex-chromosomes, and sex chromosomes or gametes

Question 35

Locus

Answer 35

the position or location on a chromosome where a given gene occurs

Question 36

alternate forms of a gene, occur at the same locus on paired chromosomes and thus govern the same trait

Answer 36

alleles

Question 37

karyotype

Answer 37

the chromosome of an individual or what is typical of a species, viewed microscopically and displayed in a photograph

Question 38

Mitosis

Answer 38

simple cell division, the process by which somatic cells divide to produce two identical daughter cells

Question 39

Meiosis

Answer 39

cell division on specialized cells in ovaries and testes, involves two division and results in four daughter cells, these can develop into gametes

Question 40

the exchange of genetic material between paired chromosomes during meiosis “crossing over”

Answer 40

Recombination

Question 41

a problem occuring during meiosis where chromosomes in fetal development do not separate

Answer 41

nondisjunction

Question 42

Clones

Answer 42

organisms that are genetically identical to another organism

Question 43

the chance distribution of chromosomes to daughter cells during meiosis. An important source of genetic variation

Answer 43

random assortment

Question 44

PCR

Answer 44

polymerase chain reaction-a method of producing thousands of copies of DNA samples for testing, allows for DNA fingerprinting