Embryonic oxygen consumption and growth of Laysan and black-footed albatross

The constraints placed on diffusive gas exchange by the eggshell and the adaptive features of embryonic respiration and metabolism in large Laysan and black-footed albatross eggs (300 g) during prolonged incubation (65 days) were examined in naturally incubated eggs on Sand Island, Midway, in the Northwestern Hawaiian Islands. A low eggshell gas conductance and slow growth rate were associated with a relatively low oxygen consumption (MO2) throughout incubation. Just prior to internal pipping (IP) of the inner shell membrane and penetration of the air space, the MO2 (pre-IP MO2) was approximately 1,250 ml O2 (STPD).day-1 for both species, resulting in air cell O2 and CO2 tensions of 106 and 40 Torr, respectively. During the 4- to 5-day pipping-to-hatching interval, O2 uptake increases rapidly as pulmonary respiration is initiated. Hatchling O2 consumption averaged 3,700 ml O2 (STPD).day-1 or about three times the pre-IP MO2. Data support the hypothesis that embryonic metabolism among Procellariiformes is related to the extent to which the incubation period deviates from the expected value based on initial egg mass.

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Time-Energy Budgets During Reproduction and the Evolution of Single Parenting in the Superb Lyrebird

Australian Journal of Zoology ◽

10.1071/zo9860351 ◽

1986 ◽

Vol 34 (3) ◽

pp. 351 ◽

Cited By ~ 17

Author(s):

A Lill

Keyword(s):

Growth Rate ◽

Brood Size ◽

Slow Growth ◽

Bird Species ◽

Egg Laying ◽

Energy Budgets ◽

Brood Care ◽

Single Parenting ◽

Slow Growth Rate ◽

Small Brood

Estimated expenditures on brood-care by unassisted female superb lyrebirds, obtained through time-energy budgeting, were compared with published values for other bird species. With the exception of nestbuilding, estimated daily expenditures were relatively low, due mainly to the small brood size and low level of parental attentiveness. It is suggested that the traits which reduce daily brood-care expenditures, particularly the small brood size and extremely slow growth rate, may have evolved as adaptations which enabled deserted females operating close to maximal capacity to cope with single-parenting. Male parental involvement could probably increase the growth rate of the young, but not brood size; moreover, egg- laying was sufficiently asynchronous to afford multiple mating opportunities to parentally emancipated males. However, the slow growth rate of the young results in relatively large overall brood-care expenditures for females. Investments by males of up to 50% of daylight hours and 45% of BMR on singing at the height of the mating season were comparable with those of partially emancipated, polygynous males of other species. They probably reflect the high level of competition to control good display areas and to advertise status and quality to widely spaced females.

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The Function of the Gills of Mayfly Nymphs from Different Habitats

Journal of Experimental Biology ◽

10.1242/jeb.16.3.363 ◽

1939 ◽

Vol 16 (3) ◽

pp. 363-373 ◽

Cited By ~ 2

Author(s):

C. A. WINGFIELD

Keyword(s):

Oxygen Consumption ◽

Oxygen Content ◽

The Body ◽

Gaseous Exchange ◽

Low Oxygen ◽

Respiratory Mechanism ◽

Tracheal Gills ◽

Cloeon Dipterum ◽

Gill Function ◽

Oxygen Concentrations

1. The oxygen consumption of normal and gill-less nymphs of the mayflies Baetis sp., Cloeon dipterum and Ephemera vulgata has been measured at various oxygen concentrations. 2. It has been found that over the complete range of oxygen concentrations studied, the tracheal gills do not aid oxygen consumption in Baetis sp. In Cloeon dipterum, at all oxygen concentrations tested, no gaseous exchange takes place through the gills; at low oxygen concentrations, however, the gills function as an accessory respiratory mechanism in ventilating the respiratory surface of the body and so aid oxygen consumption. In Ephemera Vulgata the gills aid oxygen consumption even at high oxygen concentrations. In this species the gills may function both as true respiratory organs and as a ventilating mechanism. 3. It is shown that the differences in gill function can be related to the oxygen content of the habitat of each species.

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Effect of physiological age of stem and IBA treatment on rooting of branch cuttings of Taxus baccata L.

Current Botany ◽

10.25081/cb.2018.v9.3377 ◽

1970 ◽

pp. 01-07

Author(s):

Saumitro Das ◽

L.K. Jha

Keyword(s):

Growth Rate ◽

Large Scale ◽

Slow Growth ◽

Physiological Age ◽

Taxus Baccata ◽

Practical Solution ◽

Slow Growth Rate ◽

Rooting Response ◽

Himalayan Yew ◽

Rooting Capacity

The natural population of Taxus baccata L. (Himalayan Yew) throughout the Indian Himalayan Region is greatly reduced due to its extensive and reckless exploitation for “Taxol” an anticancer drug. The effects of overexploitation are exacerbated by the species poor regeneration process, slow growth rate and prolonged seed dormancy. Therefore vegetative propagation by branch cuttings seems to be only practical solution for its large scale multiplication. A study was conducted on six candidate trees (CTs) to examine the effect genotype, physiological age of stem, IBA treatment on rooting of Taxus baccata cuttings. Results revealed that rooting behaviour of cuttings was significantly affected by all the factors under study. Among the six CTs studied, CT 2 (from BSI, Shillong) had given the highest rooting response (46.28%). The juvenile cuttings have the higher rooting capacity; however the callusing was more prominent in mature cutting. The influence of IBA treatment was also significant for rooting where 1000 was most effective for stimulating rooting juvenile cuttings and 2000 ppm in mature cuttings.

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The mitochondrial AAA protease FTSH3 regulates Complex I abundance by promoting its disassembly

Plant Physiology ◽

10.1093/plphys/kiab074 ◽

2021 ◽

Author(s):

Aneta Ivanova ◽

Abi S Ghifari ◽

Oliver Berkowitz ◽

James Whelan ◽

Monika W Murcha

Keyword(s):

Complex I ◽

Nadh Dehydrogenase ◽

Slow Growth ◽

Nadh:Ubiquinone Oxidoreductase ◽

Temperature Sensitive ◽

Wild Type ◽

Forward Genetic Screen ◽

Slow Growth Rate ◽

Partial Restoration ◽

Screen Approach

Abstract ATP is generated in mitochondria by oxidative phosphorylation. Complex I (NADH:ubiquinone oxidoreductase or NADH dehydrogenase) is the first multisubunit protein complex of this pathway, oxidising NADH and transferring electrons to the ubiquinone pool. Typically Complex I mutants display a slow growth rate compared to wild-type plants. Here, using a forward genetic screen approach for restored growth of a Complex I mutant, we have identified the mitochondrial ATP dependent metalloprotease, Filamentous Temperature Sensitive H 3 (FTSH3), as a factor that is required for the disassembly of Complex I. An ethyl methanesulfonate-induced mutation in FTSH3, named rmb1 (restoration of mitochondrial biogenesis 1), restored Complex I abundance and plant growth. Complementation could be achieved with FTSH3 lacking proteolytic activity, suggesting the unfoldase function of FTSH3 has a role in Complex I disassembly. The introduction of the rmb1 to an additional, independent, and extensively characterised Complex I mutant, ndufs4, resulted in similar increases to Complex I abundance and a partial restoration of growth. These results show that disassembly or degradation of Complex I plays a role in determining its steady-state abundance and thus turnover may vary under different conditions.

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Ustilago bullata. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056400718 ◽

1981 ◽

Author(s):

J. E. M. Mordue

Keyword(s):

Geographical Distribution ◽

Latent Infection ◽

Slow Growth ◽

Poor Survival ◽

Head Smut ◽

Slow Growth Rate ◽

North And South America ◽

North And South ◽

Leaf Distortion ◽

Infection Hypha

Abstract A description is provided for Ustilago bullata. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Agropyron, Bromus, Brachypodium, Elymus, Festuca, Hordeum, Sitanion. DISEASE: Causes head smut of grasses particularly species of Bromus and Agropyron. Sori develop at the base of spikelets and usually involve the ovary but glumes are usually unaffected, phyllody of floral parts also occurs. Latent infection with very reduced sori production can also occur. Infected seedlings show stunting and poor survival, older plants show slow growth rate and leaf distortion has been observed (56, 265). GEOGRAPHICAL DISTRIBUTION: Europe, North and South America, W. Asia (USSR, Poland, Iraq), India, Kenya, Australia, New Zealand. TRANSMISSION: Teliospores are released from the inflorescence sori to contaminate soil and seed. Teliospores have remained viable (in artificial storage) for 12 years. Germination results in the production of a metabasidium and sporidia, plasmogamy then produces a dikaryotic infection hypha. Seedlings and older shoots become infected, the former producing completely infected plants, but the latter producing separately diseased tillers (see Falloon, 1979).

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Egg Size, Eggshell Porosity, and Incubation Period in the Marine Bird Family Alcidae

The Auk ◽

10.1093/auk/124.1.307 ◽

2007 ◽

Vol 124 (1) ◽

pp. 307-315

Author(s):

Karen Zimmermann ◽

J. Mark Hipfner

Keyword(s):

Incubation Period ◽

Egg Size ◽

Interspecific Variation ◽

Egg Mass ◽

Proximate Mechanisms ◽

Diffusion Limited ◽

Evolutionary Changes ◽

Incubation Periods ◽

Avian Incubation ◽

Embryonic Metabolism

Abstract Although the ultimate factors that influence the duration of avian incubation periods are well known, we know much less about the proximate mechanisms by which birds adjust incubation period in response to selection. We tested the hypothesis that an adjustment in eggshell porosity is one such proximate mechanism (i.e., that avian species with higher ratios of incubation period to egg size lay eggs with less porous shells). Eggshell porosity affects the rate of gaseous exchange between the developing embryo and the external environment; thus, to the extent that embryonic metabolism is diffusion-limited, eggshell porosity could directly determine incubation period. To test that hypothesis, we collected eggs from seven species of Alcidae, a family of marine birds that exhibits an unusual degree of interspecific variation in incubation period, and measured egg mass and eggshell porosity (determined by the number and size of pores and the thickness of the shell). Incubation periods were obtained from the literature. Egg mass and eggshell porosity combined explained 87% of the variation in incubation period among the seven species, which included at least one member of each of the six main alcid lineages. As predicted, eggshell porosity and incubation period were negatively related, after controlling for egg mass. Our results are consistent with the hypothesis that evolutionary changes in avian incubation period may be attributed, at least in part, to adjustments in eggshell porosity. Taille de l’Œuf, Porosité de la Coquille et Période d’Incubation chez les Oiseaux Marins de la Famille des Alcidés

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Oxidative phosphorylation in cardiac infarct. Effect of glucose-KCl-insulin solution

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1965.209.2.371 ◽

1965 ◽

Vol 209 (2) ◽

pp. 371-375 ◽

Cited By ~ 28

Author(s):

Edmundo Calva ◽

Adela Mujica ◽

Abdo Bisteni ◽

Demetrio Sodi-Pallares

Keyword(s):

Oxygen Consumption ◽

Oxidative Phosphorylation ◽

Respiratory Control ◽

Low Oxygen ◽

Normal Limits ◽

Functional Aspects ◽

Insulin Solution ◽

Effect Of Glucose ◽

Infarcted Tissue ◽

Electrocardiographic Abnormalities

Myocardial infarction was produced in dogs by ligature of the anterior descending coronary artery. Sarcosomes were isolated from normal and infarcted tissue. Oxygen consumption was followed polarographically and adenosine triphosphate was measured as glucose 6-phosphate. One group of animals received a continuous infusion of glucose for 12 hr; another group received "polarizing solution" (glucose-KCl-insulin). Sarcosomes from the first had a low oxygen consumption, no respiratory control, and no oxidative phosphorylation. In contrast, the administration of glucose-KCl-insulin solution maintained practically within normal limits these functional aspects of the sarcosomes. The reversal of electrocardiographic abnormalities by the administration of the polarizing solution coincided with improvement of such biochemical functions. Anesthesia and surgical handling did not appear to modify the behavior of the sarcosomes.

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