Did you know that the majority of your body is composed of only four elements: carbon, oxygen, hydrogen, and nitrogen? These elements interact (along with others in smaller amounts) to form the major molecules and compounds in the body. How do atoms (the smallest particle of an element that retains the characteristics of that element) interact with one another? Describe the different types of chemical bonds that can be formed between atoms.

Part A - Homeostasis Overview
Homeostasis is essential to body function. The parts of a homeostatic control system communicate and work togetheInput
connect each term to the appropriate sentence describing its function within a homeostatic control system.

Control center
Stimulus
Effector
Output
Response
Receptor

: provides the means for the control center's response to the stimulus
: monitors and responds to changes in the environment
: effector feeds back to reduce the effect of the stimulus and returns the variable to homeostatic level
: control center's information sent to the effector
: determines the level at which a variable is to be maintained and analyzes the input to determine the appropriate output
: sensory information sent to the control center
: produces a change in variabler to influence changes to maintain homeostasis levels.

Part B - Summary of Homeostatic Control
Now that you have studied the components of a homeostatic control system and their roles, it is time to put that knowledge to use. In this question, you will build a homeostatic control system.
Drag and drop the items below in the appropriate order to represent a negative feedback homeostatic control system for body temperature regulation.

Muscles shiver to
produce heat.Body temperature
rises.Brain sends message
to muscles.Thermoreceptors detect
body temperature.Brain processes
temperature information.

Part C
Match the following.
Drag the terms on the left to the appropriate blanks on the right to complete the sentences.

Lateral
Distal
Superficial
Ventral
Medial
Superior
Proximal
Deep
Dorsal
1. above
2. toward the backside of the body
3. away from the midline
4. internal
5. farther from the origin of a body part or the point of attachment of a limb to the body trunk
6. toward the midline
7. external
8. close to the origin of the body part or the point of attachment of a limb to the body trunk
9. anterior

Part D
Match the following.
Drag the terms on the left to the appropriate blanks on the right to complete the sentences.

Coxal
Brachial
Superior
Tarsal
Crural
Femoral
Deltoid
Sural
Inguinal
Antebrachial
1. above
2. ankle
3. curve of shoulder
4. forearm
5. thigh
6. calf
7. hip
8. groin
9. arm
10. leg

As Americans with our vast wealth and technology, we often stereotype hunter-gathers like the Bushmen as 'primitive'. But how long could you do it? No running water, no automobiles, and (gasp!) no cell phones! Most of the skills and things you currently have would be utterly useless living of the land. How do the Bushmen do it? What skills would you have learn to survive by hunting and gathereing?

whate are the function components found in these three different vectors plasmides ,cosmides and YACs whate size fragments would you insert in to each

If a tree flowers thrice in a year (Oct., Jan. and July) in Northern India, it is said to be

(a) photo and thermo-insensitive

(b) photo and thermo-sensitive

(c) photosensitive but thermo-insensitive

(d) thermosensitive but photo-insensitive.

An adaptation for better gaseous exchange in plant leaves is

(a) hair on lower surface

(b) multiple epidermis

(c) waxy cuticle

(d) stomata on lower surface away from direct sun rays.

True or False? An antimicrobial drug with a therapeutic index of 100 would be have a higher selective toxicity than a drug with an therapeutic index of 5.

True?

True or False? Transduction is a type of horizontal gene transfer that involves the uptake of naked (extracellular) DNA by a competent recipient cell.

True?

True or False? Oxygenic photosynthesis uses water as an electron donor, while anoxygenic photosynthesis uses other molecules (e.g. H2S) as electron donors; however, both processes generate ATP by way of oxidative phosphorylation using a cyclic electron transport chain and production of a proton motive force

False?

Please check if these are correct

how might Zika lead to microcephaly? 200 or more words please

You are asked to divert resources in your research division to fund a project to identify the receptor for “excitor”, a plant derived compound which is very hydrophobic, but potent at stimulating animal neurons to grow. Your research group has been studying the effects of an agonist molecule called “excitor” in a rat model for anxiety. The agonist is potent at inhibiting anxiety, so could potentially lead to a useful therapeutic for anxiety disorders. Your company has a library of putative GPCR cDNAs for which they also have RNA expression data in numerous rat tissues. After painstaking analysis on your computer, you have found a candidate GPCR cDNA ,G77R, which is expressed in the very brain regions you see effects with “excitor”. You are convinced this cDNA may represent the cDNA for the receptor for “excitor”, the discovery of which could lead to a promotion and pay increase for you.

Describe how you will demonstrate that this cDNA G77R encodes a specific receptor for “excitor” by performing a specific receptor binding assay on whole cells. Include which cells you will use, your controls and brief descriptions of the methods used.

Just looking to understand what it means by specific receptor binding assay... would a radio labeled ligand receptor assay be an option? Would using whole cells change what assay could be used? Or is a pull down assay an option since the potential receptor is a GPCR? If so, would a pull down assay be considered an example of a specific receptor binding assay? The G77R is just a name given to the potential receptor.

Kindly write a two page summary of the content below including important details. Thank you. kindly paraphrase as well

Abstract Representing the 60 trillion cells that build a human body, a sperm and an egg meet, recognize each other, and fuse to form a new generation of life. The factors involved in this important membrane fusion event, fertilization, have been sought for a long time. Recently, CD9 on the egg membrane was found to be essential for fusion [1], but sperm-related fusion factors remain unknown. Here, by using a fusion-inhibiting monoclonal antibody [2] and gene cloning, we identify a mouse sperm fusion related antigen and show that the antigen is a novel immunoglobulin superfamily protein. We have termed the gene Izumo and produced a genedisrupted mouse line. Izumo −/− mice were healthy but males were sterile. They produced normal-looking sperm that bound to and penetrated the zona pellucida but were incapable of fusing with eggs. Human sperm also contain Izumo and addition of the antibody against human Izumo left the sperm unable to fuse with zonafree hamster eggs. Identification of Izumo To identify factors involved in sperm–egg fusion, we used a monoclonal antibody, OBF13, against mouse sperm that specifically inhibits the fusion process [2]. The antigen was identified by separation of the crude extracts from mouse sperm by two-dimensional gel electrophoresis and subsequent immunoblotting with the monoclonal antibody. We named the antigen ‘Izumo’ after a Japanese shrine dedicated to marriage. The identified spot was analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS), and ten peptides that were 100% identical to a part of the sequence listed in the RIKEN full-length database were found. The registered DNA sequence was confirmed by sequencing after polymerase chain reaction with reverse transcription (RT–PCR) with total RNA prepared from the testis. A human homologue was found as an unverified gene in the NCBI database. The gene encodes a novel immunoglobulin superfamily (IgSF), type I membrane protein with an extracellular immunoglobulin-like domain that contains one putative glycosylation site (Fig. 1a). Mouse Izumo was shown to be a testis (sperm)-specific 56.4-kDa antigen by western blotting with a polyclonal antibody raised against recombinant mouse Izumo (Fig. 1b). Izumo was also detectable as a 37.2-kDa protein by western blotting of human sperm with anti-human Izumo antibody (Fig. 1c). Izumo was not detectable on the surface of fresh sperm. Coinciding with the fact that mammalian sperm are incapable of fertilizing eggs when ejaculated and that fertilization occurs only after an exocytotic process called the acrosome reaction, both mouse and human Izumo became detectable on sperm surface only after the acrosome reaction (Fig. 1d, e). This would probably be because Izumo is not localized on plasma membrane of fresh spermatozoa but is hidden under plasma membrane and accessible after the acrosome reaction, as occurs with CD46 on mouse sperm [3]. Figure 1 Identification and characterization of Izumo. a, Izumo is a typical type I membrane glycoprotein with one immunoglobulin-like domain and a putative N-glycoside link motif (Asn 204). b, Izumo was detected exclusively in testis and sperm by western blotting. The tissues examined are, from left to right: brain, heart, thymus, spleen, lung, liver, muscle, kidney, ovary, testis and sperm. The arrowhead indicates mouse Izumo protein. c, Western blotting analysis of human Izumo protein from human sperm. The arrow indicates human Izumo protein. d, Immunostaining of Izumo in sperm from an acrosin-promoter-driven transgenic mouse line that has enhanced green fluorescent protein in the acrosome. Izumo was not detected in fresh sperm with intact acrosomes expressing EGFP (indicated by green arrows), but was revealed on acrosome-reacted (non-green fluorescent) sperm (stained red, shown by white arrowheads), when stained with the polyclonal antibody against mouse Izumo. e, Human sperm were also stained with polyclonal anti-human Izumo antibody (red). Acrosome-reacted human sperm (stained green with anti-CD46 antibody) were reactive to the antibody against human Izumo but the same antibody did not react to acrosome-intact (CD46-negative) sperm. Scale bar, 10 mm. 40 ANNUAL REPORT OF OSAKA UNIVERSITY—Academic Achievement—2004-2005 Establishment of Izumo-deficient mice To address the physiological role of Izumo in vivo we generated Izumo-deficient mice by homologous recombination. An Izumo targeting construct was designed to replace exons 2–10 with a neomycin-resistant gene (neor ). Both the targeting event in D3 embryonic stem cells and the germline transmission of targeted genes were confirmed by Southern blot analysis. In the homozygous mutant mice, the full-length messenger RNA and the Izumo protein were not detected. Because the disruption of a gene can cause a concomitant increase or decrease in some related genes, we examined CD46, sp56, CD55, CD147, and ADAM2, which were reported to be involved in sperm–egg interactions. We could not find a significant change in these protein levels in sperm after the deletion of Izumo gene. The fecundity of Izumo-deficient males Izumo −/−mutant mice were healthy and showed no overt developmental abnormalities. Izumo -/- females demonstrated normal fecundity. Izumo +/− males also showed normal fertilizing ability. However, Izumo −/− males were sterile despite normal mating behaviour and ejaculation, with normal vaginal plug formations. After observation of 28 plugs, nine pairs of Izumo −/− male and wild-type females were kept for another 4 months but no pregnancies were observed. In at least four different cases of gene knockouts that resulted in male sterility attributed to impaired zonabinding ability, the sperm also failed to migrate into the oviduct. However, disruption of Izumo did not cause any defect in sperm migration into the oviduct (data not shown, and there was no reduction of sperm motility in Izumo −/− sperm motility was measured 120 min after incubation by computer-aided sperm analysis (CASA; mean; s.e.m.=81.7±7.7% in Izumo +/− sperm and 77±8.9% in Izumo −/− sperm)). The sterile nature of Izumo −/− sperm was shown in the in vitro fertilization system (Fig. 2a). The impaired fertilization step undoubtedly followed zona penetration because sperm penetrated the zona pellucida and accumulated in the perivitelline space of the eggs (Fig. 2b). Fusion ability in Izumo-deficient sperm Syngamy can be considered to occur to two stages: binding of the sperm plasma membrane to that of the egg, and actual membrane fusion. Izumo −/− sperm were capable of binding to the plasma membranes of eggs whose zona pellucida had been mechanically removed [4] (Fig. 2c). In this system, the Izumo +/− sperm incubated for 2 and 6 h fused to eggs in approximate ratios of 4.5 and 6 sperm per egg, respectively, but no Izumo −/− sperm fused with eggs (Fig. 2c). Sperm can not fuse with eggs unless the former have undergone the acrosome reaction. To verify the acrosomal status of Izumo −/− sperm, we stained the sperm accumulated in perivitelline spaces with the MN9 monoclonal antibody, which immunoreacts only to the equatorial segment of acrosomereacted sperm [5]. The staining indicated that the Izumo −/− sperm had undergone the acrosome reaction (Fig. 2b) but failed to fuse with eggs. Development of eggs after intracytoplasmic sperm injection (ICSI) with Izumo-deficient sperm Because no offspring were fathered by Izumo −/− male mice, it was unclear whether the defect was limited to fusion or extended to later developmental stages. To address this question, we used ICSI to insert Izumo −/− sperm directly into the cytoplasm of wild-type eggs and bypass the fusion step. Eggs injected with Izumo −/− sperm were successfully activated and the fertilized eggs were transplanted into the oviducts of pseudopregnant females. The eggs implanted normally and the resulting embryos developed appropriately to term with rates similar to those of heterozygous mice. Human Izumo is also involved in sperm-egg fusion Sperm–egg fusion is known to be less species-specific than sperm–zona interaction. For example, human sperm can not penetrate the hamster zona pellucida but they can fuse with zona-free hamster eggs, and this system (zona-free hamster-egg sperm penetration test) has been used for the assessment of human sperm fertility. We first examined the contribution of mouse Izumo in a zona-free hamster-egg sperm penetration assay. As indicated in Fig. 3a, the mouse Izumo was essential not only in the homologous fusion system but also for heterologous fusion with hamster eggs. Similarly, when the anti-human Izumo polyclonal antibody was added to the incubation mixture, no fusion was observed, whereas the sperm treated with control IgG fused with eggs at an average of 5.9±0.7 sperm per egg. The total numbers of eggs observed were 23 and 29, respectively (n=3). These results indicated that human Izumo is involved in the fertilization process in human sperm (Fig. 3b). Rescued fertility of Izumo-deficient male by transgene The phenotypes of gene knockout mice are not always related Figure 2 Male infertility caused by Izumo disruption. a, In vitro fertilization of sperm from Izumo +/−and Izumo −/−mice. Unlike Izumo +/−, the eggs inseminated with Izumo −/− sperm had many sperm on their zona pellucida, owing to the failure of sperm–egg fusion that probably leads to the absence of zona-reaction to lessen the sperm-binding ability of the zona pellucida. b,Upper panel, accumulation of many sperm in the perivitelline space of the eggs recovered from the females mated with Izumo −/− males. Lower panel, sperm in perivitelline space labelled with acrosome reacted, spermspecific monoclonal antibody MN9. c, Fused sperm stained by Hoechst 33342 preloaded into the egg. The arrowheads show the fused sperm. to the disrupted genes but are sometimes caused by disruption of a neighbouring gene. To examine whether the phenotype was directly derived from the lack of Izumo on sperm, we performed a rescue experiment by crossing Izumo −/− mice with transgenic mouse lines generated to express Izumo by using the testis-specific calmegin promoter [6]. The sterile phenotype was rescued with the transgenically expressed Izumo on mouse sperm (Fig. 4). Discussion In the search for sperm surface proteins that function in sperm–egg plasma-membrane binding and fusion, various candidates such as DE, CD46, equatorin, Sperad and SAMP32 have been reported. ADAM family proteins are given the most attention for their possession of a putative fusion peptide (ADAM1) and disintegrin domain (ADAM2 and ADAM3). None of the mice possessing disrupted ADAM1a, ADAM2 and ADAM3 show a significant defect in the ability to fuse with eggs [7-9], but do show an impairment of sperm–zona binding ability. Similarly, CD46 disruption does not diminish fusion [3]. In contrast, CD9 on the egg surface is essential for the fusing ability of eggs [1] and some indications for the involvement of the binding of integrins to CD9 are postulated in reference to sperm–egg fusion. However, the disruptions of the most probable candidate integrin α6β1 cause no major influence on the fusing ability of eggs. Thus, for several years, postulated fertilization mechanisms were repeatedly changed as a result of gene disruption experiments. This suggests that the essential nature of the candidate gene must be judged after observing the phenotype of the gene-disrupted mice. In this context, Izumo is the first sperm membrane protein shown to be essential for fusion. It is not yet known whether sperm Izumo interacts with egg CD9, as occurs with placental IgSF protein PSG17; neither do we know why the localization of Izumo after acrosome reaction is not limited to the 41 Osaka University 100 Papers : 10 Selected Papers ANNUAL REPORT OF OSAKA UNIVERSITY—Academic Achievement—2004-2005 Figure 4 Transgene to express mouse Izumo under the control of calmegin promoter. a, The locations of primers A to E were indicated in this figure. b, lane 1; Izumo +/− mouse with intrinsic Izumo, lane 2 and 3; Izumo −/− mouse with transgenically expressed Izumo and Izumo His-tag, respectively. c, Litter size obtained by mating male mice with C57BL/6 wild-type mice. The group numbers are equal to those shown in b. The numbers in parentheses indicate the numbers of matings. References 1. Miyado, K. et al., Requirement of CD9 on the egg plasma membrane for fertilization. Science, 287, 321-4 (2000). 2. Okabe, M. et al., Capacitation-related changes in antigen distribution on mouse sperm heads and its relation to fertilization rate in vitro. J Reprod Immunol, 11, 91-100 (1987). 3. Inoue, N. et al., Disruption of mouse CD46 causes an accelerated spontaneous acrosome reaction in sperm. Mol Cell Biol, 23, 2614-22 (2003). 4. Yamagata, K. et al., Sperm from the calmegin-deficient mouse have normal abilities for binding and fusion to the egg plasma membrane. Dev Biol, 250, 348-57 (2002). 5. Manandhar, G. & Toshimori, K., Exposure of sperm head equatorin after acrosome reaction and its fate after fertilization in mice. Biol Reprod, 65, 1425-36 (2001). 6. Ikawa, M. et al., Calmegin is required for fertilin alpha/beta heterodimerization and sperm fertility. Dev Biol, 240, 254-61 (2001). 7. Cho, C. et al., Fertilization defects in sperm from mice lacking fertilin beta. Science, 281, 1857-9 (1998). 8. Nishimura, H., Cho, C., Branciforte, D. R., Myles, D. G. & Primakoff, P., Analysis of loss of adhesive function in sperm lacking cyritestin or fertilin beta. Dev Biol, 233, 204-13 (2001). 9. Nishimura, H., Kim, E., Nakanishi, T. & Baba, T., Possible Function of the ADAM1a/ADAM2 Fertilin Complex in the Appearance of ADAM3 on the Sperm Surface. J Biol Chem, 279, 34957-62 (2004). equatorial segment where fusion initially takes place. All we can say now is that continued study of this protein’s function will undoubtedly lead to a fuller understanding of the cell–cell fusion process in fertilization and perhaps in other somatic systems such as muscle cells or trophoblasts. The finding not only provides insight into the enigmatic fusion mechanism but also promises benefits in the clinical treatment of infertility and the potential development of new contraceptive strategies

Three genes with recessive mutant phenotypes are located on the same chromosome in maize: short stem (ss), purple aleurone (pr), and knotted leaf (kn). A plant with all three mutant phenotypes is crossed with a true-breeding, wild-type plant. Resulting F1 plants are then backcrossed to the parental mutant line to produce the following progeny:   (7 points)

Short        Purple     Knotted       Number
ss                       +                  kn                   2342
+                        pr                 +                    2297
ss                       pr                 kn                   4095
+                        +                  +                    3963
+                        +                  kn                   979
ss                       pr                 +                    992
ss                       +                  +                    77
+                        pr                 kn                   75
        
         A.   How many non-recombinant progeny were identified?
         B.   How many of the F2 plants contained a crossover between the short stem and knotted leaf genes?
         C.   Draw a chromosome map with the correct distances (rounded to one decimal point) noted                                           between adjacent pairs of genes.
         D.   What is the gene order and arrangement of alleles for the P and F1 plants used in these crosses?

A number of human-mouse somatic cell hybrid closes were examined for the presence or human chromosomes and the expression of specific human genes. Part of the results are summarized in the table below. Assign each gene to the chromosome on which it is located.

Applying your knowledge of metabolism, glycolysis starts with one molecule of glucose (6C) and produces a net total of __________.

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Applying your knowledge of metabolism, glycolysis starts with one molecule of glucose (6C) and produces a net total of __________.

1. Put the general step in order necessary to create bacteria capable of producing human insulin.

step 1

step 2

step 3

step 4

step 5

a. splice the human insulin DNA into the bacterial plasmid

b. Cut the bacteria plasmid with HindIII

c. Treat bacterial to induce transformation

d. culture bacteria and isolate the protein

e. cut the bacteria plasmid with BamH1

f. isolate and cut the human insulin gene with BamH1

2. Human DNA cut with BamH1 can be joined to

a. human DNA cut with HindiIII

b. bacteria DNA cut with BamH1

c. Human DNA that is uncut

d. none of the above

e. bacterial DNA that is uncut

3. which of the following could not be a recognition site of a palindromic restriction endonuclease?

a. GAATTC

CTTAAG

b. ATCGAT

TAGCTA

c. CTGCAG
GACGTC

d. GCTTGC

CGAACG

e. GGATCC

CCTAGG

4. Because eukaryotic genes contain introns, they cannot be translated by bacteria, which lack RNA-splicing machinery. But if you want to engineer a bacterium to produce a eukaryotic protein (such as insulin), you can synthesize a gene without introns. The best way to do this is to:

a. alter the bacteria so that they can splice RNA

b. Use a restriction enzyme to remove introns from the gene

c. work backward from mRNA to make a version of the gene without introns

5. The gene for human growth hormone (HGH) can be inserted into the genome of bacteria. The bacteria that take up the HGH gene can transcribe and translate this gene into small quantities of this protein. How is this technology possible?

a. bacteria employ the same genetic code as humans

b. Humans require HGH grow normally.

c. Reproductive cloning is possible only in bacteria

d. The genomes of bacteria and human are similar

6. In the process of gel electrophoresis, DNA segment can be separated from each other based on?

a. the ratio of thymine to adenine base-pairs compared to cytosine to guanine base-pairs

b. the fact that some segments are negatively charged while others are positively charged.

c. the fact that some of the DNA will be single-stranded while others will be double-stranded

d. the length of each base-pair segment

7. which of the following is not true about restriction endonucleases?

a. restriction endonucleases cut in an internal region of the DNA

b. Restriction endonucleases are used by bacteria to cut viral DNA

c. restriction endonuclease can produce "sticky ends."

d. Restriction endonucleases are only useful to scientists if they cut specific recognition sites.

8. you are given a linear piece of DNA Gel electrophoresis and restriction digestion results in the following data:

DNA + Ecoli produces two bands of 800bp and 200 bp

DNA + BamHI produces one band of 500 bp

DNA + Ecoli + BamHI produces three bands of 500bp, 300bp, and 200bp

Which of the following is not true?

a. there is a single Ecoli recognition site in the DNA

b. There are two Ecoli recognition sites in the DAN

c. There is a single BamHI recognition site in the DAN

d. the uncut DNA would produce a single band of 1.000bp

9. sequences in DNA that restriction enzymes bind to and cut are mostly:

a. random sequences

b. symmetrical about the midpoint

c. antiparallel

d. not symmetrical about the midpoint.

10. the single strand ends of DNA molecules can be joined together by:

a. restriction endonucleases

b. DNA polymerase

c. RNA polymerase

d. DNA ligase

11. If a circular piece of DNA has three sites for a particular restriction enzyme, how many fragments will be generated by complete digestion with that enzyme .................