structure and arrangement of photoreceptors in the retina of big eye kilka, clupeonella grimmi (kessler 1877)

نویسندگان

al et

h. khalili

چکیده

the big eye kilka, clupeonella grimmi, is a marine fish living in depth of 20 to 200 meter of the caspian sea. its eye and retina were processed for histological and sem studies. paraffin embedded retina was cut radially and tangentially in 5 ?m thickness and stained with hematoxylin and eosin method. the unstained sections were manipulated for sem image observations. tangential retinal sections showed irregular arrangement of cones. five morphologically different types of photoreceptors were distinguished as rods, short single cones, long single cones, twin cones and double cones. the cones were counted in each quadrant of the retina and cone density was determined. the cones showed increment in diameter but reduction in number at anti-clockwise direction without any specific arrangement. presence of four types of cone cells and their pattern of distribution revealed assistance in near surface color vision and more light capture in dim light of deeper waters as an adaptation to planktivorous feeding habit and deep water living habitat.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Structure and arrangement of photoreceptors in the retina of big eye kilka, Clupeonella grimmi (Kessler 1877)

The big eye kilka, Clupeonella grimmi, is a marine fish living in depth of 20 to 200 meter of the Caspian Sea. Its eye and retina were processed for histological and SEM studies. Paraffin embedded retina was cut radially and tangentially in 5 ?m thickness and stained with hematoxylin and eosin method. The unstained sections were manipulated for SEM image observations. Tangential retinal sect...

متن کامل

Age and growth of bigeye kilka (Clupeonella grimmi Kessler, 1877) in Iranian waters of the Caspian Sea

Age and growth of Bigeye Kilka, Clupeonella grimmi, were studied in Iranian waters of the Caspian Sea from early May 2006 to April 2007. The sagitta otoliths were removed for each 5 mm length interval up to a total number of 262 fish. Fork length and weight ranged from 92.5 to 142.5 mm and 4.2 g to 23.4 g, respectively. The largest length-groups was observed from December to February and the lo...

متن کامل

Age and growth of bigeye kilka (Clupeonella grimmi Kessler, 1877) in Iranian waters of the Caspian Sea

Age and growth of Bigeye Kilka, Clupeonella grimmi, were studied in Iranian waters of the Caspian Sea from early May 2006 to April 2007. The sagitta otoliths were removed for each 5 mm length interval up to a total number of 262 fish. Fork length and weight ranged from 92.5 to 142.5 mm and 4.2 g to 23.4 g, respectively. The largest length-groups was observed from December to February and the lo...

متن کامل

Effect of Clupeonella grimmi (anchovy/kilka) fish oil on dysmenorrhoea.

To examine whether dietary supplementation with omega-3 fatty acids from Clupeonella grimmi can relieve symptoms of dysmenorrhoea, we carried out a cross-over clinical trial on 36 girls aged 18-22 years. They were randomly allocated into 2 groups of 18. Group A received 15 mL fish oil daily (550 mg eicosapentaenoic acid; 205 mg decosahexaenoic acid) while Group B received placebo. After 3 month...

متن کامل

the underlying structure of language proficiency and the proficiency level

هدف از انجام این تخقیق بررسی رابطه احتمالی بین سطح مهارت زبان خارجی (foreign language proficiency) و ساختار مهارت زبان خارجی بود. تعداد 314 زبان آموز مونث و مذکر که عمدتا دانشجویان رشته های زبان انگلیسی در سطوح کارشناسی و کارشناسی ارشد بودند در این تحقیق شرکت کردند. از لحاظ سطح مهارت زبان خارجی شرکت کنندگان بسیار با هم متفاوت بودند، (75 نفر سطح پیشرفته، 113 نفر سطح متوسط، 126 سطح مقدماتی). کلا ...

15 صفحه اول

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید


عنوان ژورنال:
caspian journal of environmental sciences

ناشر: university of guilan

ISSN

دوره 12

شماره 1 2014

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023