Quiz 1 Deck

Question 1

List the three major divisions of genetics and what each includes

Answer 1

Transmission : focused on individual, refers to how traits are passed on from one generation to next

Population: explore the genetic composition of populations and how they change geographically over time, focus is on the GROUP of genes in a population

Molecular: looking at gene itself, gene structure, formation organization

Question 2

describe common features of most model genetic organisms

Answer 2

-short generation time
-large but manageable population size
-adaptability for lab
-inexpensive to house and propagate
-the availability of numerous genetic variants
-an accumulated body of knowledge about their genetic systems

Question 3

compare the theory of pangenesis and the germ plasma theory

Answer 3

PANGENESIS: NOT TRUE CONCEPT, EACH PART OF BODY CONTAINS GENETIC INFO gemmules, carry information from parts of the body to the reproductive organs, then passed to embryo at the moment of conception

Germ-plasm theory : A CORRECT THEORY
weismann, cells in reproductive organs carry a complete set of genetic into that is passed to the egg and sperm, egg and sperm has info already

Question 4

define preformationism

Answer 4

a concept of herdity where inside the egg is a fully formed minature adult; a homunculus, that simply enlarges in the course of development
all traits inherited from only one parent

Question 5

explain blending inheritance

Answer 5

traits of offspring area blend or mixture of parental traits (mom red hair dad blue hair kids purple hair)

Question 6

compare the different concepts of heredity

Answer 6

correct ones are mendalian, germ plasm, and cell theory the rest are all incorrect

Question 7

briefly describe mendels contribution to genetics

Answer 7

traits are inherited with defined principles, depends on what trait is to see how/what is inherited.
his conclusion of monohybrid crosses
- one character is encoded by two genetic factors
-two genetic factors (alleles) separate when gametes are formed
the concept of dominant and recessive traits
-two alleles separate with equal probability into the gametes

Question 8

compare eukaryotic and prokaryotic cells

Answer 8

Prokaryotic cells are single celled with an absolute nucleus and they are relatively small prokaryotic cells usually have one circular DNA molecule DNA are not complex with histones in bacteria some histones in Archea a relatively small amount of DNA and membrane bound organelles are absent

Eukaryotic cells are unicellular or multicellular they have a present nucleus and they are relatively large they have multiple linear DNA molecules to form a genome in their DNA is complexed with histones the amount of DNA is relatively large membrane-bound organelles are present

Question 9

give definition of a gene

Answer 9

they are the fundamental unit of heredity
Come in multiple forms called alleles
Confer phenotypes
Are located on chromosomes

Question 10

explain the relationship between genes and alleles

Answer 10

genes come in multiple forms called alleles

a gene is an inherited factor(encoded in the DNA) that helps determine a characteristic

Question 11

explain the relationship between genotype and phenotype

Answer 11

a genotype is a set of alleles possessed by an individual organism

a phenotype (or trait) is the APPEARANCE or manifestation of a characteristic

Question 12

explain the relationship btwn genes and chromosomes

Answer 12

Genes are located on chromosomes

chromosomes seperate through mitosis and meiosis

Question 13

briefly describe the function of mitosis and meiosis

Answer 13

Mitosis purpose is cellular proliferation CELLULAR DUPLICATION, chromosome number remains the same and genetic variation doesn’t change, 2 diploid daughter cells produced

meiosis’s purpose is sexual reproduction, chromosome number is halved in each daughter cell and genetic variation is increased, 4 haploid daughter cells are produced

Question 14

explain the relationship between DNA,RNA, and proteins

Answer 14

DNA -> RNA -> PROTEINS IS CENTRAL DOGMA,

GENETIC INFO IS CARRIED IN DNA AND RNA

DNA contains the information necessary for encoding proteins, although it does not produce proteins directly. RNA carries the information from the DNA and transforms that information into proteins that perform most cellular functions

Question 15

define mutation

Answer 15

Mutations are permanent changes

Question 16

explain how traits are affected by multiple factors

Answer 16

Most traits are shaped both by a person’s genes and by environmental factors. Environmental factors include everything outside of DNA that affects your traits. They are very broad and can influence you in many ways, either alone or in combination with genes.

Question 17

describe how evolution occurs

Answer 17

evolution is genetic change overtime
chromosomal duplication can influence evolution
reprodcution alone will not bring about evolution

Question 18

explain the relationship of bacteria and eukaryotes

Answer 18

The leading hypothesis, called the endosymbiotic theory, is that eukaryotes arose as a result of a fusion of Archaean cells with bacteria, where an ancient Archaean engulfed (but did not eat) an ancient, aerobic bacterial cell.

Antibiotics that do not inhu=ibit protein synthesis in eukaryotes inhibit protein synthesis in bacteria and mitochondria
The most obvious difference between eukaryotes and bacteria is that there is a membrane-bounded nucleus in eukaryotes and not in bacteria

Question 19

decribe the process of binary fission in prokaryotes

Answer 19

a part of cell reproduction
binary fission: separation of replicated circular chromosome

Question 20

describe 3 functional elements of eukaryotes chromosome and their functions

Answer 20

chromatin: complex of dna and proteins
histone proteins : the most abundant proeitns in chromatin
nucleosome: consist of DNA wrapped around an octamer of eight histone proteins

centromeres: constricted region of a chromosome where spindle fibers attach
telomeres: end of chromosomes that stabilize the chromosomes

Question 21

summarize the key genetic consequences of the cell cycle

Answer 21

Cycle produces two cells that are genetically identical to each other and the parental cell

new cells contain approximately half the cytoplasm and organelle content of the original parental cell

cytoplasm and genetic cells not necessarily identical

Question 22

predict the number of chromosomes and number of DNA molecules found in a cell at different stages of the cell cycle

Answer 22

G1: 4 chromosomes per cell and 4 Dna molecules per cell
S: 4 chromomes per cell and 4-8 DNA
G2 4 chromosomes and 8 DNA molecule per cell
Prophase and prometaphase: 4 chromome and 4 DNA
Metaphase: 4 chromosomes and 8 DNA molecules per cell
Anaphase : 8 chromosomes and 8 DNA molecules
Telophase and cytokinesis: 4 chromosomes and 4 DNA

Question 23

outline the important events that occur in each stage of meiosis

Answer 23

Meiosis describes the process of cell division by which gametes are made. In this process, we begin with a cell with double the normal amount of DNA, and end up with 4 non-identical haploid daughter gametes after two divisions.

There are six stages within each of the divisions, namely prophase, prometaphase, metaphase, anaphase, telophase and cytokinesis.

https://teachmephysiology.com/biochemistry/cell-growth-death/meiosis/#:~:text=In%20this%20process%2C%20we%20begin,%2C%20anaphase%2C%20telophase%20and%20cytokinesis.

Meiosis I
In meiosis I, homologous chromosomes are separated into two cells such that there is one chromosome (consisting of two chromatids) per chromosome pair in each daughter cell, i.e. two chromosomes total.

Prophase I
Prior to prophase, chromosomes replicate to form sister chromatids. There are initially four chromatids (c) and two chromosomes (n) for each of the 23 chromosome pairs (4c, 2n). The nuclear envelope disintegrates and the chromosomes begin to condense. Spindle fibres appear which are important for the successful division of the chromosomes.

To further increase genetic diversity, homologous chromosomes exchange small parts of themselves, such that one chromosome contains both maternal and paternal DNA. This process is known as crossing over, and the points at which this occurs on a chromosome are referred to as chiasmata.

Prometaphase I
Spindle fibres attach to the chromosomes at points along the chromosomes called centromeres. While this is happening, the chromosomes continue to condense.

Metaphase I
Maternal and paternal versions of the same chromosome (homologous chromosomes) align along the equator of the cell. A process called independent assortment occurs – this is when maternal and paternal chromosomes line up and randomly align themselves on either side of the equator. This in turn determines which gamete chromosomes are allocated to, which leads to genetic diversity among offspring.

Anaphase I
Here, each of the homologous chromosomes is pulled towards opposite poles of the cell as the spindle fibres retract. This equally divides the DNA between the two cells which will be formed.

Telophase I and Cytokinesis I
During telophase I, the nuclear envelope reforms and spindle fibres disappear. In cytokinesis I, the cytoplasm and cell divide resulting in two cells that are technically haploid – there is one chromosome and two chromatids for each chromosome (2c, n).

Question 24

summarize the key genetic consequences of meiosis

Answer 24

Four cellls are produced from each originial cell

chromosome number in each new cell is reduced by half

newly formed cells from meiosis are genetically different from one another and from the parent cell

Question 25

explain how crossing over leads to genetic variation

Answer 25

Crossing over happens in meiosis 1 and it is an exchange of genetic material between homologous but non sister chromatids generating genetic variation

Question 26

explain why sister chromatids seperate in anaphase of mitosis but do not separate until anaphase 2 of meiosis

Answer 26

They remain attached and travel together to increase genetic variability, when they split in anaphase 2 of meiosis and pulled to opposite poled each chromatid is now a distinct chromosome

Question 27

Identify factors that led to Mendel’s success in discovering the principles of heredity.

Answer 27

used pea plant moel which is easy to replicate and had a rapid grow rate

also had a successful experiment where he did not have many variations to see the true target

Question 28

Explain the principle of independent assortment

Answer 28

alleles at different loci separate independently of one another, genes located close together on the same chromosome do not assort independently (will travel together during phase1 of anaphase meiosis unless crossing over takes place

Question 29

Explain how the principle of independent assortment results from the separation of chromosomes
in meiosis

Answer 29

alleles at different loci separate independently in anaphase 1

Question 30

Interpret the probability obtained from a chi-square goodness of fit test.

Answer 30

The calculated value of Chi-Square goodness of fit test is compared with the table value. If the calculated value of Chi-Square goodness of fit test is greater than the table value, we will reject the null hypothesis and conclude that there is a significant difference between the observed and the expected frequency.