radha3217

Two brown-eyedparents are each heterozygous for a recessive blue-eye gene. Whatis the probability that the first two children will beblue-eyed?

Short answers please

1. What is the ultimate effect in an XY human with its SRY genemutated?

2. In humans, the allele for brown eye (B) is dominant to blue(b) eye color. If two heterozygous parents produce children, whatis the probability that:

a. The first child has brown eyes, and the next two childrenhave blue eyes?

b. If the couple above eventually produces a total of sixchildren, what is the probability that three of them will be boyswith brown eyes, and three of them girls with blue eyes?

3. In a paternity dispute, a type AB woman claimed that one ofthe four men was the father of her type A child. Which of thefollowing men could be the father of the child on the basis of theevidence below? Give your reasoning.

Man #1 = type A

Man #2 = type B

Man #3 = type O

Man #4 = type AB

4. Several mating were made among all-white cats. The progentfrom these mating showed the following phenotypic frequency:

All-white cats = 12/16

Black cats = 3/16

Gray cats = 1/16

a. Diagram the cross showing the genotypes of the parents, andtheir progeny as given above,

b. Which gene is epistatic? Explain your answer.

5. Mitosis and meiosis differ in that

a. homologues are seperated in prophase of mitosis

b. homologues are seperated in prophase I of meiosis

c. homologues are seperated in prophase II of meiosis

d. sister chromatids are seperated in prophase I of meiosis

6. The phases of meiosis that most resemble those of mitosisare

a. the meiosis I phase

b. the meiosis II phase

c. meiosis I, except for the pairing of homologues

d. meiosis II, except for the pairing of homologues

7. Genetic variability in sexually reproducing organism s arisesfrom

a. crossing over events between sister chromatids

b. crossing over events between nonsister chromatids

c. egg and sperm genetic recombination from distinctindividuals

d. egg and sperm recombination from an individual

8. A female contains an extra X chromosome, resulting fromnondisjunction. When this gamete is fertilized with normal sperm,it would result in an individual of a genotype

a. XXX

b. XXY

c. XYY

d. all of the above

e. only a and b

9. A diploid organism has the genotype AaBbCcDdEe. How manydifferent types of gametes can this individual produce?

a. 5

b. 10

c. 25

d. 32

e. 625

10. Assuming complete dominance, what is the phenotype ratio ofthe offspring of the cross AaBb x aabb?

a. 1:1

b. 3:1

c. 1:2:1

d. 1:1:1:1

e. 9:3:3:1

I just want to confirm few questions and some I am throughly confused with...

Q.3) What is asymmetrically distributed during an asymmetric cell division (DNA or cytoplasmic molecules)?
Answer: I think it's cytoplasmic molecules....I just want to confirm...

Q.4) How do cells get the morphogen inside if the morphogen is a transcription regulator?

Q.5) Give examples of signaling molecules involved in inductive signaling during development

Q.6) Does a larva have segments, or just an adult fly?
Answer: I believe that just adult fly..but I want to confirm this...

Q.7) Are the posterior and the anterior ends predetermined before fertilization? Are the dorsal and the ventral sides predetermined?

Q.8) What are the factors, determining the egg polarity? Are they coded by mother or zygote genes?

Q.9) Which protein segmental expression pattern persists throughout the life?
Answer: Is it protein engrailed???

Q.10) What is the Hox complex?

Q.11) Are homeotic genes expressed according to their order in the genome?

Q.12) What is the positional memory of an imaginal disc?

Thank you so much :D

1. When does differentiation begin in fruit fly (insects)?

a. Prior to fertilization

b. Just after fertilization, but before any cell divisions takeplace

c. Just after the first cell division

d. At the blastula stage

e. At the globular embryo stage

2. When does differentiation begin in frog (vertebrates)?

a. Prior to fertilization

b. Just after fertilization, but before any cell divisions takeplace

c. Just after the first cell division

d. At the blastula stage

e. At the globular embryo stage

3. When does differentiation begin in flowering plants?

a. Prior to fertilization

b. Just after fertilization, but before any cell divisions takeplace

c. Just after the first cell division

d. At the blastula stage

e. At the globular embryo stage

4. Which axis develops first in animals, anterior-posterior(A-P) or dorsal-ventral (D-V)?

a. A-P

b. D-V

c. They develop at the same time.

d. They are controlled by the same transcription factors at thesame time.

5. Which axis develops first in plants, anterior-posterior ordorsal-ventral?

a. A-P

b. D-V

c. They develop at the same time.

d. Plants only develop A-P, and with respect to gravity andlight.

6. Focusing in on A-P development in Drosophila, maternaltranscription factors produce

proteins that control axis development in what order?

a. bicoid and nanos proteins; caudal and hunchback proteins; gapand pair-rule

proteins

b. caudal and hunchback proteins; bicoid and nanos proteins; gapand pair-rule

proteins

c. gap and pair-rule proteins; bicoid and nanos proteins; caudaland hunchback

proteins

d. gap and pair-rule proteins; caudal and hunchback proteins;bicoid and nanos

proteins

7. What ultimately controls pattern formation in Drosophila?

a. Morphogen gradients and signaling molecules under maternalcontrol

b. Morphogen gradients and signaling molecules under embryoniccontrol

c. De-repressors and signaling molecules under maternalcontrol

d. De-repressors and signaling molecules under embryoniccontrol

PLANT STRUCTURE, CELLS, CELL WALLS, PLASMODESMATA

8. Which of the following cannot be found in leaves?

a. Xylem

b. Phloem

c. Mesophyll

d. Parenchyma

e. Apical meristem

9. What are intercalary meristems?

a. Meristems that develop between internodes in some plants

b. Meristems that develop primary meristematic tissues

c. Meristems that are responsible for secondary growth in woodyplants

d. Root meristems

10. Roots, shoots, and leaves all contain three basic tissuesystems. What are they?

a. Ground, structural, conductive

b. Ground, vascular, dermal

c. Vascular, dermal, structural

d. Conductive, transmissive, supportive

11. All growth in plants is due to

a. Cell division in the three basic tissue systems andsubsequent cell elongation

b. Cell division at meristems and subsequent cell elongation

c. Cell division as needed throughout the plant body, followedby cell elongation

d. Hormone-induced cell division throughout the plant body

12. Which plant cells are dead at maturity, although stillproviding some useful function?

a. Dermal

b. Ground

c. Xylem

d. Phloem

e. Lateral meristems

13. Which meristems are responsible for lateral growth (increasein girth)?

a. Apical meristem

b. Root meristem

c. Vascular and bark cambium

d. Intercalary meristem

14. Where are most guard cells generally located in vascularplants?

a. Stem dermal tissue

b. Root dermal tissue

c. Petiole dermal tissue

d. Undersides of leaves

e. Uppersides of leaves

15. How can you distinguish guard cells from non-guardcells?

a. They contain mitochondria

b. They contain chloroplasts

c. They do not have plasmodesmata

d. They have plasmodesmata

e. B and C

PINs, IAA, ACID GROWTH

16. What are PINs?

a. Plasma membrane transport inhibitors

b. Auxin efflux transporters for active transport across plasmamembranes

c. Growth regulators

d. Hormones

e. Membrane transport proteins for embryogenesis

17. What is IAA?

a. Cytokinen

b. Gibberellic acid

c. Florigen

d. Auxin

e. Abscissic acid

18. Which hormone can trigger cell wall expansion?

a. Cytokinen

b. Gibberellic acid

c. Florigen

d. Auxin

e. Abscissic acid

19. Which ion is used by plants to decrease pH and activateenzymes that break cress-bridges

between cellulose fibers for cell wall expansion?

a. Na

b. K

c. Cl

d. H

e. Mg

20. Where do the ions come from to cause acidification of thecell wall?

a. Apoplast

b. Cytoplasm

c. Chloroplasts

d. Mitochondria

e. Vacuole

PLANT EMBRYOGENESIS, SHOOT APICAL MERISTEM (SAM), ROOT APICALMERISTEM

(RAM)

21. The first cell division in a plant zygote isasymmetrical.

a. True

b. False

22. At what stage of embryogenesis do PIN proteins firstinfluence orientation of the root-shoot

axis?

a. First cell division

b. Second cell division

c. 8-cell stage

d. Globular stage

e. Heart-shaped stage

23. Which hormone most strongly affects cell division inembryos?

a. IAA

b. GA

c. Ethylene

d. AA

e. CK

24. How do the major tissue systems in plants become establishedin developing embryo?

a. Anticlinal cell divisions

b. Periclinal cell divisions

c. All of the above

d. None of the above

STEM/ROOT PRIMARY, SECONDARY GROWTH

25. Fifteen years ago, your parent hung a swing from the lowerbranch of a tree in your yard. It is at the exact same height as itwas then. Why isn

1• T/F: many (species) embryos show anatomical asymmetry immediately at fertilization •

T/F: many (species) embryos show genetic or sub-cellular asymmetry immediately at fertilization •

T/F: In some instances, mRNAs and proteins already have polarized distributions before fertilization occurred, meaning some aspects of embryonic polarity is maternally determined

2. The mid-blastula transition describes the point of development where: (could be multiple correct responses) a. Zygotic gene transcription initiates b. Zygotic gene transcription terminates c. Maternal gene transcription initiates d. Maternal gene transcription terminates •

Which axis is specified by fertilization and cortical rotation in the frog embryo? a. A-P b. D-V •

In Xenopus development the mesoderm derives from the: a. Vegetal pole cells b. Marginal zone cells c. Animal cap cells •

Liver, lungs, and pancreas are derived from a. endoderm b. ectoderm c. mesoderm

2-4 Explain the earliest mechanisms specifying each germ layer • XNR/Nodals are _____________ factors acting as morphogens to specify mesoderm. a. Secreted b. Intracellular

Why is it that starch is not digested in the stomach 

ellular totipotency is demonstrated by

(a) only gymnosperm cells

(b) all plant cells

(c) all eukaryotic cells

(d) only bacterial cells

Which of the following statement associated with your endodermal research papers is NOT correct? Select one:

Select one:

a. Long-term loss of Cdx2 led to a partial conversion of the intestinal epithelium to a stomach-like nature.

b. Pdx1 is not involved in pancreatic bud specification.

c. Foxa1 and Foxa2 are required for uptegulating Pdx1 expression in the pancreatic buds.

d. Foxa proteins are required to make the endoderm competent to respond to FGF and form liver.

e. Upregulation of Sox2 in the foregut leads to an inability to separate into the trachea and esophagus.

name the largest cell