جستجوی مقالات مرتبط با کلیدواژه « development » در نشریات گروه « زیست شناسی »

Cadmium belongs to the group of heavy metals and is one of the most important environmental pollutants that enters the body of living organisms in different ways and causes damage to them. So far, many studies have been conducted on the dangers of cadmium on living organisms, but no study has been conducted on the teratogenic effects of cadmium on mice. Therefore, the aim of the present study was to study the teratogenic effects of cadmium on different stages of the embryonic development of Balb/c mice. In this study, 40 Balb/c mice with a weight range of 26±4 g were used. Mice were randomly divided into 4 groups. Each group have 10 mice. Experimental groups 1, 2, and 3, respectively, received doses of 6.25, 12.5, and 25 μg/g of cadmium with a volume of 0.1 ml, and the control group received the same volume of distilled water daily orally. The results of the study analyzed by ANOVA method. The rsults showed: The number of mice embryos, the number of live embryos, the length of the hind limbs, the length of the front limbs, the length of the tail, the length of the cephalo-caudal embryos and the weight of the embryos were reduced in compared to the control group but the number of reabsorbed embryos, the number of abnormal embryos, compared to the control group, it has increased significantly. Therefore, cadmium has a teratogenic effect on the different stages of embryo development of Balb/c mice and causes various morphological abnormalities in them.

Canola with the scientific name Brassica napus L., due to its high oil content in the seed, produces one third of all edible oils worldwide, which plays an important role in improving the nutritional needs of societies. Accelerated aging test is one of the most important tests used to evaluate the viability and physiological potential of seeds. Unsuitable environmental conditions as well as seed storage conditions can cause oxidative stress in seeds and other plant tissues. In this study, the improvement effect of pretreatment of vitamin C and Hydroquinone on canola seed under accelerated aging and the developmental and phytochemical characteristics of seedlings obtained from aged canola seed including morphological traits, germination indices and phytochemical changes were investigated. Pre-treatment of seeds with antioxidant compounds reduced the damage caused by decay, improved the quality of canola seeds and seedlings, and also changed the phytochemical composition of the seedlings. The reduction of seed germination and weak morphometric characteristics of seedlings obtained from old seeds indicate the relationship between the phytochemical changes of seeds and the aging process. Seedlings obtained from old seeds showed phytochemical changes in the metabolic pathways of carbohydrates and proteins. If the aging process of the seed does not lead to death of seed, the resulting seedlings will have a different destiny with high power to deal with oxidative stress. It seems that the seedlings receive the signal from the free radicals of seed aging and cause the growth of intelligent seedlings to deal with the stress.

Understanding the relationship between climate-based habitat conditions and survival is key to maintaining biodiversity in the face of rapid climate change. Water is a limiting habitat variable for amphibians because larvae must metamorphose before wetlands or ponds dry up. Changes in precipitation and temperature patterns globally affect the amount of water available, but the impact of these changes on amphibian growth, development, and survival is poorly understood. In this study, the effect of water level reduction on the growth, metamorphosis, and survival of Levant green frog (Pelophylax bedriagae) larvae in three treatments (control, moderate, and rapid water level reduction) was investigated for 129 days. In each tank, 50 larvae were subjected to the same diet with 4 replications. The results of the experiment showed that reducing the water level increases the growth rate. Treatments with moderate and rapid water reduction showed a decrease in the size of metamorphosis, a decrease in the duration of metamorphosis, and a decrease in survival compared to the control treatment. The statistical results showed that the effect of these treatments on metamorphosis time and metamorphosis size is significant but insignificant on growth rate and survival. This information can provide insight into the plasticity of this species under climate change.

Due to its great medicinal value, the Moldavian dragonhead, belonging to Lamiaceae, is naturally distributed in Europe, Siberia, and Central Asia and planted in different Iranian provinces. This research studied the development of male/female reproductive organs. Flowers and buds in different stages of development were fixed and preserved in order to prepare microtome sections using appropriate solutions and embed them in paraffin. Hematoxylin-eosin was used to stain the slices. Based on the results, despite the relative simultaneity of the formation of stamen primordium and carpel, stamens develop faster than ovules. Nurses’ cells in secretory and plasmodium types are rectangular, spindle-shaped, and often mononuclear or more. The microspore’s tetrads had tetrahedral ornamentations, and mature pollen grains were hexacolpate with reticulate ornamentation of the exine. The ovules were anatropous, unitegmic, and tenuinucellate. The functional megaspore has a micropillar position, and the embryo sac development belongs to the Polygonum type.

Glutathione s transferase (GST) is one of the largest protein and multigene families present in all plant species and other living organisms. With respect to these proteins, which are highly ‌inducible to stress and internal and external stimuli, several functions in plants have been identified, including implication in secondary metabolism, growth and development, detoxification of herbicides, as well as coping with environmental stresses such as drought, heat, and salinity through antioxidant activity. These enzymes lead to cell detoxification by binding glutathione to a variety of substrates such as endobiotics and xenobiotics. Most GSTs are cytoplasmic soluble enzymes, but mitochondrial and microsomal isoforms are also have been known in plants and animals. This article presents some of the most important recent findings on the evolution of GST, its frequency and structural features, with an emphasis on their role in plants. Also, the latest applications of this family of proteins in environmental biotechnology will be mentioned.

Among the squirrel family (Sciuridae), the yellow ground squirrel (Spermophilus fulvus) has the longest summer sleep. Summer sleep of these squirrels begins in late winter and continues until late February. The aim of the present study was Evaluation of Embryonic Development in Yellow Ground Squirrels (Spermophilus fulvus) and Electrophoresis Comparison of Serum and Cytogenetic Proteins of TheseSquirrels with Gray Squirrels (Spermophilus xanthoprymnus) (Mammalia: Rodentia) in Iran.

In this project, a large number of babies were collected from several nests in May, and their development was examined in the laboratory.In this way, it was found that these squirrels give birth once a year, with 5-7 babies per calving.48 squirrels (28 males and 20 females) were collected from northeastern Iran (Mashhad and Bojnourd), western Iran (Kurdistan, Hamedan, Qazvin, and Zanjan), and northeastern Iran (Pīr Aḩmad Kandī, Kelisay-e Kandy, and Nadu village) to identify the species of ground squirrel (Spermphilus).The globulin and albumin proteins of all samples were first tested using the SDP-PAGE technique.

According to the results, in the sedimentary range of globulin proteins (G = Globulin), the samples collected from northeastern and western Iran formed 5 electrophoretic bands and those collected from northwestern Iran formed 11 electrophoretic bands.Besides, in the sedimentary range of albumin proteins (A = Albumin), the samples collected from northeastern and western Iran formed only one electrophoresis band and those collected from northwestern Iran formed 4 electrophoretic bands.During the karyological studies according to the method proposed by Ford and Hamerton, karyotypes were obtained from bone marrow cells to confirm the results of electrophoresis studies on the distribution of two of these squirrels in the collection areas in Iran.The results indicated that the karyotype of the samples collected from northeastern Iran (Mashhad) and western Iran (Qazvin, Hamedan, Zanjan, and Kurdistan) had 36 diploid chromosomes (2n = 36) and that the karyotype of the samples collected from northwestern Iran (Mako) had 42 diploid chromosomes (2n = 42).

According to the results of electrophoresis and karyological methods, among ground squirrels, Sprmophilus fulvus species are distributed in northeastern and western Iran and Spermophilus xanthoprymnus species are distributed in northwestern Iran.

We have developed a basic three-dimensional finite difference hydrodynamic oceanic model using baroclinic primitive equations based on the earth's spherical coordinate modified by vertical sigma coordinate with eleven levels equivalent to five layers to study the thermodynamics of wind-driven currents. In this basic model, we consider an enclosed rectangle area, with constant depth of 120 m. We have simulated the horizontal velocity fields, salinity and temperature distributions by forcing the model with the steady bellowing wind over the area for four days with the speed of 10 m/s and direction . According to the Rossby number of the order of one tenth thousands, the large scale processes are dominated in the middle of such basins.The salinity and temperature of the layers are changed due to the diffusion and convection terms in the salinity and temperature equations, respectively.

This study was conducted to determine the effect of cold plasma on growth and anatomical features of Foeniculum vulgareL. plants.

After preparation, fennel seeds were exposed to cold plasma irradiation for 0, 5, 10, and 20 minutes. After germination and initial growth of seedlings, the anatomical features of roots stems and leaves grown from seeds treated with cold plasma were investigated using Carmen Zaji staining.

The results showed that cold plasma was able to make changes in the pattern of differentiation of xylems of the fennel plant, which was mainly dependent on cold plasma time. These changes include an increase in the size of xylem cells and a change in the distribution pattern of the vascular system in the leaves, stems, and roots.

It was concluded that cold plasma treatment causes changes in the anatomical features of leaves, stems , and roots, which can be responsible for the beneficial effects of cold plasma on seed germination characteristics and early plant growth.

Finger length ratios are organized during embryonic development of fingers as they exposed to sex steroid hormones, and may show varying degrees of sexual dimorphism between males and females in different animal groups. Among all the finger length ratios calculated in a sample, the ratio between the second to fourth fingers (2D: 4D) is the most important one. In this study, the 2D:4D ratios in both sides of the body (right and left) in all limbs were investigated to determine if sexual dimorphism is present in the 2D: 4D ratios in 44 specimens studied (20 males and 24 females) of Acanthodactylus blanfordi. Other morphological traits of the two sexes were also examined (23 metric and meristic traits), as a result, sexual dimorphism was observed in five metric and meristic morphological traits. In terms of the ratio of the size of the fingers and toes, sexual dimorphism in the length of the fingers was observed only in 2D: 4D on the right side of the body in forelimbs and hindlimbs. The value of this trait was higher in males than females and this difference was statistically significant P ≤0.05).

Sexual dimorphism in the ratio of digits length is a morphological feature resulted from the interaction between sex hormones and prenatal Hox genes, the latter is known to control the development of both limbs and genitals. The status of this trend and ratios have been investigated in various animal groups, including humans, other mammals, birds, reptiles, and amphibians. In this study, the body length and sexual dimorphism in the second-to-fourth, second-to-third and third-to-fourth digit lengths ratios (i.e., 2D:3D, 2D:4D, 3D:4D) of left fore and hind limbs were investigated in 54 specimens of toads collected from the northern Iran, including Bufo viridis (16 males and 19 females) and Pelobates syriacus (10 males and 9 females). In addition, the body length of the studied specimens were recorded. The results showed that the average body length (SVL) of female individuals of Pelobates syriacus was higher than those in males, which was found to be statistically significant (P≤0.05). Meanwhile, the average body length (SVL) of female individuals of Bufo viridis was found to be higher than those in males, however, the difference was not statistically significant. No sexual dimorphism was detected in the second-to-fourth, second-to-third and third-to-fourth digit lengths ratios of left fore and hind limbs between the male and female undividuals of Bufo viridis. However, the second-to-fourth digit ratio (2D:4D) in Pelobates syriacus species were found to be significantly different (P=0.040) between the male and female individuals, as the ratio was higher in males than females. Therefore, it could be concluded that the sexual dimorphism in 2D:4D of Pelobates syriacus species is consistent with those in most amphibians and diapsids.

Bunium persicum (Boiss.) B.Fedtsch is a family member of Apiaceae which fruits are considered as an important export in food and pharmaceutical industries. According to the significant role of the mentioned native plant and necessity of becoming familiar with the anatomical and developmental structures, some samples of this plant were collected in the current study. Moreover, the vegetative and generative parts were investigated using cell - histological methods include of the fixation with F.A.A fixator, preparation, embedding in paraffin, slices the samples, staining with Hematoxylin- Eosine utilizing stereomicroscope and optical microscopes.Preposition of results, the apical part of root is tuberiformis and leaves are polymorphic with anemocytique Stoma .The flower structure consists of 5 sepals, 5 petals, and 5 stamens, biloculate and inferior ovary. Furthermore, secretory canals were observed in all parts of the plant. The anther was tetra-sporangiate, the tapetum was of secretory type and also the shape of mature pollens was oval. The results of female reproductive organ showed the presence of anatropus ovule with one layered integuments and development of the embryo sac is of polygonum type.

The environmental conditions which the parent plant has undergone during seed development can affect many properties of the seeds such as degree of dormancy, weight and the amount of their compounds. In this study, mature pistachio seeds of Ahmadaghaei cultivar, collected from the two cities of Rafsanjan and Shahrbabak located in Kerman Province (Iran), were compared. It was found that the seeds collected from Shahrbabak being a cooler and wetter region had a longer dormancy, although the water content of the two seed series were similar. Dehydrin proteins generally play a role in protecting plant cells against dehydration stress. Dehydrin contents of the cotyledons and embryonic axes of the two seed series were compared by western blot method using an antibody against the conserved K segment in dehydrin proteins. It was found that the cotyledons had five dehydrin versions with molecular weights of 23, 25, 32, 39 and 48 kDa, the expression of which not being influenced by environmental factors. It was found that the embryonic axes had seven other versions of dehydrin with weights of 17, 19, 20, 28, 67, 77 and 98 kDa in addition to those five versions. This shows higher protection of embryonic axes compared with the cotyledons. The 25 and 28 kDa versions had higher expression levels in embryonic axes of Shahrbabak seeds, while the 39 kDa version had a higher expression level in embryonic axes of Rafsanjan seeds.

Age, stage of plant development, and vegetative and reproductive growth stage at harvesting time are effective and important factors in determining the content of secondary metabolites in medicinal plants. In the present study, the variation of essential oil in Artemisia absinthium L. was studied. Sampling of cultivated plants was carried out from the plants grown in the field of Agricultural Research and Education Center of Hamadan province at three phonological stages of five years old plants (vegetative, beginning of flowering, full flowering) and vegetative stage of one year old plants picked in the early morning. The essential oil was extracted by Clevenger's apparatus and essential oil was analyzed by GC and GC/MS. A total of 40 different components were identified. The main component of essential oil in all samples was (z) -B-Ocimene oxide. The amount of (z) -B-Ocimene oxide in a one-year plants, a five-years plants at vegetative stage, a five-years old plant at the beginning of flowering stage and five years old at the stage of full flowering were 76.53%, 47.84%, 66.59% and 52.93%, respectively. Among the other dominant components of the plant, carvacrol and sabinene can be mentioned wich the highest level of carvacrol (7.27%) was observed in vegetative stage and Sabinene (4.44%) at full flowering stage of five years old plants.

Inroduction & Objective: Breeding carp species included common carp, grass carp or amor, silver carp or phytophagus and bighead.This study has been doneonimpact of button mushroom compost as an alternative and fertilizer on tissues structure of four cultured warm water species. Material and For this purpose juveniles a month with an average weight of 69.60 ± 1.28g for two months in six pool werefed with button mushroom compost and fertilizers in warm water fish culture at Shahid Ahmadian Khorramshahr. During breeding,treatment groups and control were fed by button mushroom compost and chemical fertilizer. At the end of the stipulated time and biometrics,5 millimeter tissue samples removed from primary, middle and end part of the intestine.Then rutine procedure of tissue preparation was done and sections staining with (H & E), studied by light microscope equipped with Dinolite lens. The results indicated an increase in the number of mucus cells in common carp and silver carp in the treatment group, an increase in the thickness of epithelium in the bighead in the control group, an increase in muscle layer thickness in grass carp and silver carp in the control group and an increase in the length of villi in bighead and silver carp in the treatment group with compost(p≤ 0.05). Therefore, it can be reported that in the recent study, the use of compost, has a positive effect on various parts of the intestinal in most cultured warm water species, because the compounds in it make the food easy to get in the species has been studied.For this purpose, compost can be used as a suitable alternative for enrichment in cultured warm water species.

Medicago sativa L is from Fabaceae family that has several flavonoid compound in roots and shoots. Medicarpin is a dominant isoflvonoid that induces in nodul of root in different stage of developmentl. In this study, PAL (phenyl alanine amonialyase) activity was assayed using spectrophotometer. In this rse arc the concentration of medicarpin evaluete by HPLC (high performance liquid chromatography) were studied in different stages of development. The anatomical structure of leaves, stem, root and nodules were studied in transversal section by optical microscope. Different tissue such as epiderme, pharanshime, vascular systeme includes xylem and pheloem, were studied, measured and which are shown in different tabels.The results indicated that activity of PAL enzyme are altered during the plant development stage and changes of medicarpin content were correlated to the activity of PAL enzyme.The highest level of production of medicapin and activity of PAL enzyme have been observed during of growth in root.

Aim: The treatment of the electromagnetic field is a the physical pretreatments of seed to increase yield of plants. In this paper, the effects of electromagnetic fields on seed germination and growth parameters of Nigella sativa L. were investigated.
In the study dry and wet seeds are exposed to two electromagnetic fields strength of 1.6 and 0.8 mT for 30 minutes and seed germination were evaluated. 3 months after sowing the Growth and development of seedlings was investigated.
Dry seeds germination comparing to wet and control seeds had a significant increase. Plant samples of dry pre-treated seeds, showed significant reduction in time to start flowering in both the intensity of the electromagnetic fields, (p These studies show that electromagnetic fields can affect seed germination and plant growth and development.

The present study aimed to investigate the possibility of developing and promoting organic agriculture in Qom province from the viewpoint of agricultural experts. The present research is applied in terms of purpose, in terms of data collection, monitoring, and degree of control of variables and generalizability of descriptive - correlation type that has been done by survey method and using a questionnaire tool. The spatial and geographical scope of this research is at the level of experts in Jihad-e-Agriculture Organization in Qom. In this research, the statistical simulation of the present study included experts working in the Department of Agricultural Production, Agricultural and Agricultural Research Institute, Scientific and Applied Higher Education Institution, and Agricultural Research Institute of Agriculture and Rural Development, affiliated with the Ministry of Jihad-e-Agriculture. Their number was 320. For sampling, stratified random sampling with proportional assignment was used among the statistical population. The sample size is 175 experts who have obtained the Morgan table. In this study, two main methods of documentary and field studies were used to collect information. In the field stage, a questionnaire was used to collect information. The questions were designed using theoretical foundations and research hypotheses. After determining the validity and validity of the necessary corrections, a field study was used to complete and fill it. To assess the reliability of the questionnaire, 20 copies of it were completed by the same statistical society as the similar statistical society. The completed questionnaire was evaluated using SPSS 16 software and Cronbach Alpha method. The obtained alpha coefficient was also 89%. The results of Spearman correlation coefficient showed that the viewpoint of agricultural experts regarding the educational / extension factors, technical factors and the possibility of developing and promoting organic farming at 1% error rate is significant. Using step-by-step method, two variables of educational factors and technical factors were entered into the multivariate regression equation, which ultimately explained these independent variables of 0.32% of the dependent variable variations.