Biology 2107                                                                                                  Spring,  2023

Test #2

 

Name: __________________________            Student ID:  __________________

 

 

Section 1A (22 pts)

Please circle the letters that precede the most appropriate answer to the question asked.  Be aware, there is only one answer to each question.  

 

1.   The ABO blood groups in humans are determined by a multiple allelic system in which IA and IB are codominant with each other and are both dominant over iO.  If an infant (whose blood type is O is born to a type O mother, possible genotypes for the father are……(careful)?

 

A   O or A

B   A or B

C   O only

D   O, A or B

E   A only

 

2.  As you know, in Labrador retrievers, the allele for a black coloured coat (B) is dominant to the allele for brown fur coat colour (b). However, if a lab has two copies of the "recessive allele" for a "pigment-depositing gene" (e), it can only have yellow coloured fur. In a cross of two doubly heterozygous black labs (BbEe x BbEe), what fraction of the next generation would one expect to have yellow fur?

 

A.            3/8

B.             1/8

C.             1/16

D.            1/4

E.             5/8

 

3.  If two genes experience independent assortment, which assumption is most likely true?

 

A.            Crossing over between the genes does not occur

B.             The two genes are located in very close proximity to each other on the same chromosome  

C.             The two genes are located on different chromosomes or are far from each other on the same chromosome

D.            The two genes are located on the X chromosome

E.             The expression of one gene masks the expression of the other

 

4.   Chiasmata are most clearly present in:

 

A.             Anaphase II of Meiosis

B.             Prophase I of Meiosis

C.            Metaphase of Mitosis

D.            G phase 2 of Mitosis

E.             Telophase II of Meiosis

F.             Prophase of Mitosis

 

 

 

5.  In the simplified version of atomic structure -referenced in the lectures..

How many electrons does the element Argon (one of the “inert, Noble” gases) have in its outermost

electron shell?

 

F.             1

G.            3

H.            5

I.               8

J.              7

 

6.   Similarly, how many electrons does a chloride ion have in its outermost electron shell?

 

A.             1

B.             2

C.            5

D.            8

E.             7

 

7.  Mendel’s 2nd law  states that:

 

A   During gamete formation the segregation of one gene pair is independent of all other gene pairs

B   Two members of a gene pair segregate from each other into the gametes, whereby one half of the gametes carries one of the traits, the other half carries the other       

C   The union of one gamete from each parent to form a resultant zygote is random with respect to that particular characteristic.

D   When fertilization occurs, the zygote gets one half of its chromosomal set from each parent, thus restoring the pair.

 

8.   If the atomic weight of sodium is 23, and the atomic weight of chlorine 35.5.  When 58.5 milligrams of sodium chloride are dissolved in a final volume of one liter of water, the solution is said to be:

 

A.             1 molar

B.             58.5 molar

C.            1 millimolar

D.            I cannot tell, because I don’t know whether sodium chloride is formed between ionic or covalent bonds

E.             23 micromolar

F.             12.5 molar

 

9.   Which one of the following statements is true.

 

A.       Acids accept H+; bases donate H+

B.       If a compound increases the OH+ ion concentration when added to water, then the compound is said to be acidic

C.      All acids dissolve fully in water

D.     pH is a measure of hydrogen ion (H+) or more correctly hydroxonium ion (H30+) concentration in a solution

E.     The pH value is defined as the positive logarithm of hydrogen concentration in moles per liter (molar concentration).

F.       Acids, such as hydrochloric acid, have a very HIGH pH

 

10.   The term “Monoecious” refers to:

 

      G.      the number of chromosomes in a cell

      H.      the presence of both male and female structures exhibited by the same individual

                organism

      I.       the presence of only male or female structures exhibited by the same individual organism

      J.       the number of membranes present in a Gram positive bacterium

      K.      a genetic unit of hereditary

 

11.   In a suburb of East London (England) called Lower-East Hempstead, an allele at a unique locus on the Y chromosome of the men in this community gives rise to a phenomenon called “blurred-vision”.   Assuming that this is a closed community, which one of the following answers would best describe the F1 generational offspring of a “blurred-visioned” male and a phenotypically normally visioned female.

 

      A       All offspring will have blurred-vision

      B       Half the offspring will have blurred-vision

      C       All the male offspring would die

      D       Half the female offspring would have blurred-vision, the other half would be “carriers”

      E       All offspring will have normal vision

 

 

 
Section 1  (12 pts).
In the next several questions each question is worth 3 pts. 
Please circle your evaluation of the statement given.  If you believe the statement to be “False” then explain why you think so in the space provided.
 
Read each question carefully !

 

13.   With respect to proteins the term Tertiary structure” refers to the 3D organization of protein subunits in

            a complex protein, resulting in the final structure of a protein, like haemoglobin. 

 

True                                                               False

 

__the statement refers to “quaternary structure” _______________________________

 

14.   During Mitosis microtubular spindle fibres attach to the chromosomes through “kinetochores”.

 

True                                                               False

 

____________________________________________________________________

 

15.       Macromolecules can be considered to be a molecule, whose molecular weight is greater than 1,000 Daltons 

 

True                                                               False

 

____________________________________________________________________

 

16.     The “Golgi apparatus” is an organelle in eukaryotes that modifies newly synthesized proteins for “export”  and passage around the cell

 

True                                                               False

 

____________________________________________________________________

 

 

 

 

 

Section 2 (50 pts) Please answer the following questions in the space provided, using short, concise answers.

 

 

2.1. (a) (2pts) Give an example of a disaccharide.

 

_______Sucrose__________________________________________________

 

       (b) (2pts) Give an example of an amino acid or any lipid .

 

_______Glutamate, Glutamine Cysteine etc.  or triglycerides, some hormones eg. testosterone, wax,_lipid bilayers__________

 

       (c) (6pts) Define TWO major differences and ONE similarity between proteins or (lipids) and carbohydrates.

 

______CH2O, ring structure, alpha carbon, “amino “acid” _______________________

 

______lipids are not really polymers… CHO, ___VERY hydrophobobic___________________________________

 

______each form macromolecules … through removal of water, contain carbon, hydrogen oxygen_

 

____________________________________________________________________

 

____________________________________________________________________

 

____________________________________________________________________

 

____________________________________________________________________

 

____________________________________________________________________

 

____________________________________________________________________

 

____________________________________________________________________

 

____________________________________________________________________

 

 

 

2.2. (a) (5 pts.) Give one example of an “Extension” to Mendelian Genetics

 

_______Table

Description automatically generated

 

 

       (b) (7 pts.)  Define what is meant by the term “sex-linked” inheritance, giving an example.

In your answer give some explanation as to why a family tree of such a sex-linked trait would be quite different

from that of a typical Mendelian trait. 

 

Diagram

Description automatically generated

 

_Far from any 1:1 or 3:1 or All heterozygotes________________________________________

 

 

2.3. (10 pts.)

 

  (a)  (5 pts) Differentiate between an ionic bond and a covalent bond -giving an example

   of each.

 

___Diagram

Description automatically generated

 

As opposed to sharing of electrons_____________________________________________________

Shape, polygon

Description automatically generated

 

NaCl and Methane, Glucose?, Benzene?

 

                        and EITHER

 

 (b)  (5 pts) (What is a “hydrogen bond”?  Give two examples of where you might find one.

 

Diagram

Description automatically generated

DNA base pairs..

 

                                    OR

 

 (b)  (5 pts) What molecular interactions between what kind of entities give rise to curly hair –naturally,

or induced by a visit to the hairdresser.

 

Diagram

Description automatically generated

 

2.4. (5 pts.)

 

To what does the term “Cytoplasmic inheritance” refer?  In your answer, please give an example.

 

___Only female gamete will carry the “extranuclear” DNA_____

 

Extranuclear Inheritance- Cytoplasmic Factors and Types - Genetics -  Microbe Notes

 

 

     2.5. (8 pts.)

 

Why is water such an excellent solvent?

 

____________________________________________________________________

 

 

__________A picture containing diagram

Description automatically generated

__________________________________________________________

 

 

  2.7(a). (2 pts.)  YOU WILL NEED A CALCULATOR

 

What is the Hardy Weinberg equation?

 

____p2 + 2pq + q2 = 1 ___________________________

 

2.7(b). (3 pts.)  

 

The frequency of two alleles in a gene pool is 0.20 (A) and 0.80(a). If you

assume that the population is in Hardy-Weinberg equilibrium

 

Calculate the fraction or percentage of heterozygous individuals in the population

 

PLEASE show your working out.

 

Heterozygous is 2pq, which equals 2 *(0.2 * 0.8 )  2 * 0.16  =0.32 or 32%.

 

 

BONUS QUESTION (3 pts.)

 

Give one example, which was given in lecture where the Hardy Weinberg principle might actually be useful in proving something, one way or the other?  Quickly explain your answer

 

_Effectively, it is a “null hypothesis” for ANY analysis, eg. chromium plant in in Hinkley Ca.

 

____________________________________________________________________

Text

Description automatically generated

 

____________________________________________________________________