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Articles 271 - 300 of 367

Full-Text Articles in Biology

Hplc Analysis Of Myoglobin Tryptic Peptides From Selected Species Of Cetaceans, David Lawrence Hayteas Feb 1990

Hplc Analysis Of Myoglobin Tryptic Peptides From Selected Species Of Cetaceans, David Lawrence Hayteas

Dissertations and Theses

Due to the large gaps in the fossil record, the evolutionary history of the mammalian order Cetacea is incomplete and controversial. Increasingly researchers are utilizing molecular and biochemical procedures to supplement cetacean paleontology. One of these methods is the comparison of amino acid sequences of myoglobin among species of this order. since this method is time-consuming and expensive, an alternative procedure is desirable.

As a candidate for such an alternative, peptide mapping was performed on selected species of cetaceans. This mapping was done utilizing High Performance Liquid Chromatography (HPLC). Myoglobin was extracted from skeletal muscle, purified, digested with trypsin, the …


Dna Fingerprinting Analysis Of Captive Asian Elephants, Elephas Maximas, Laura Louise Bischof Jan 1990

Dna Fingerprinting Analysis Of Captive Asian Elephants, Elephas Maximas, Laura Louise Bischof

Dissertations and Theses

This thesis examined the effectiveness of DNA fingerprinting analysis for paternity ascertainment and the establishment of relatedness of captive Asian elephants (Elephas maximas). Eighteen Asian elephants from three North American zoos were examined. Thirteen of these elephants were wild caught. Relationships between these elephants and the remaining elephants born in captivity were known.


Methionine Metabolism In Fasciola Hepatica, Carol Theresa Ayer Jan 1990

Methionine Metabolism In Fasciola Hepatica, Carol Theresa Ayer

Dissertations and Theses

5'-Deoxy-5'-methylthioadenosine (MTA) is derived from s-adenosylmethionine (AdoMet) during the synthesis of the polyamines spermidine and spermine. Methionine can be regenerated from MTA by one of two mechanisms. In mammalian cells and some microorganisms, MTA is degraded to adenine and 5-methylthioribose-1-phosphate (MTR-1-P) via MTA phosphorylase. In certain other microbes, however, MTA is catabolized in two steps; first to adenine and 5-methylthioribose (MTR) via MTA nucleosidase followed by conversion of MTR to MTR-1-P via MTR kinase.

This study was to demonstrate the presence of MTA nucleosidase or MTA phosphorylase in both redia containing cercariae and adult Fasciola hepatica Linnaeus, 1758. If MTA …


Analysis Of Mitochondrial Dna Restriction Fragment Patterns In Killer Whales, Orcinus Orca, Tracy Alison Stevens Apr 1989

Analysis Of Mitochondrial Dna Restriction Fragment Patterns In Killer Whales, Orcinus Orca, Tracy Alison Stevens

Dissertations and Theses

The mitochondrial DNA restriction fragment patterns of killer whales (Orcinus orca) were investigated in order to determine the level of genetic differentiation that exists between killer whales from various geographic locations. Twenty one killer whales were examined, seventeen of which were captive killer whales that originated from the North Atlantic and Northeast Pacific Oceans. Two were captive-born animals and two were killer whales that stranded along the Northeast Pacific coast.

DNA was extracted from blood and/or tissue samples, cleaved with a variety of restriction endonucleases and the DNA fragments were separated by horizontal agarose gel electrophoresis. The DNA …


Seasonal Trailing Behavior And Corticosterone Levels In Male Red-Sided Garter Snakes (Thamnophis Sirtalis Parietalis), Pamela Kay Thinesen Jan 1989

Seasonal Trailing Behavior And Corticosterone Levels In Male Red-Sided Garter Snakes (Thamnophis Sirtalis Parietalis), Pamela Kay Thinesen

Dissertations and Theses

Mechanisms of how red-sided garter snakes (Thamnophis sirtalis parietalis) travel up to 18 km from summer feeding sites to hibernation dens are not understood. In this study, monthly and seasonal trailing behavior were investigated to determine whether red-sided garter snakes prefer to follow trails of snakes from the same den (den-mates) versus trails made by other conspecifics (non-den-mates). Snakes from five different hibernacula in Manitoba, Canada, were involved in the study. Eighteen were adults and 15 were subadults. Subadult red-sided garter snakes do not return to hibernacula until their second year of life, so their trailing behavior was of interest …


Nitrogen And Iron Interactions In Filamentous Cyanobacteria, David Allen Hutchins Jan 1989

Nitrogen And Iron Interactions In Filamentous Cyanobacteria, David Allen Hutchins

Dissertations and Theses

The investigations described in this paper are an attempt to further define and quantify the interrelationship of nitrogen fixation and iron nutritional physiology in these two species. Chapter II will present and compare data on nutritional ratios of field collected Trichodesmium colonies and laboratory Anabaena cultures, with the intent of examining possible correlations between observed iron levels and protein nitrogen and chlorophyll concentrations, as well as nitrogen fixation rates. Chapter Ill is an examination of nitrogen fixation and siderophore production in Anabaena with emphasis on the possible implications of hypothesized synergistic effects of these two physiological capabilities on cyanobacterial dominance …


Intestinal Granules Found In The Parasitic Nematodes Ancylostoma Caninum, And Oesophagostomum Radiatum, Alan Joseph Gianotti Sep 1988

Intestinal Granules Found In The Parasitic Nematodes Ancylostoma Caninum, And Oesophagostomum Radiatum, Alan Joseph Gianotti

Dissertations and Theses

The parasitic nematodes Ancylostoma caninum and Oesophagostomum radiatum were collected and analyzed for intestinal inorganic granules. Three means of identification were utilized to determine the composition granules, including birefringence, x-ray diffraction and energy dispersive spectrometric (EDS) analysis. Initial x-ray diffraction results of the two worms showed a calcium sulfide presence within the worms. Closer examination of the granules within Ancylostoma caninum however, utilizing EDS analysis revealed their composition to be zinc sulfide. These results concur with those of Rogers (1940) and Clark (1956) who found zinc sulfide granules in several species of Strongylus. The ZnS granules seem to be …


The Distribution Of Zooplankton In Selected Oregon Lakes, Mary Elizabeth Claska Aug 1988

The Distribution Of Zooplankton In Selected Oregon Lakes, Mary Elizabeth Claska

Dissertations and Theses

Zooplankton samples were collected from 166 Oregon lakes. The lakes included a wide range in size, trophic status, and water quality. Lakes were located throughout the state. Zooplankton were identified using standard taxonomic keys and counted. Seventy-four species were identified from the 200 total samples, including 32 species of cladocera, 22 copepods, and 11 rotifers. Two species of copepod were recorded for the first time in Oregon: Diaptomus mississippiensis and Diaptomus pallidus. Seven species had widespread distributions throughout most of the watersheds in the state. Seventeen other species had distributions restricted to eastern, central, or western Oregon. The remaining …


Determination Of Homology Between The Arsenic Resistance Plasmids R45 And R773 In Escherichia Coli, Joshua T. Clark May 1988

Determination Of Homology Between The Arsenic Resistance Plasmids R45 And R773 In Escherichia Coli, Joshua T. Clark

Dissertations and Theses

The resistance transfer factor R45 from Escherichia coli confers inducible arsenate and arsenite resistance in that bacterium. The genes for these resistances were cloned into the EcoR1 - Sph1 multiple cloning site of PGEM3 Blue vector (Promega) to produce a 4.9 kilobase plasmid, pJC1. This recombinant plasmid, pJC1, conferred IPTG induced resistance to arsenite and arsenate. In addition, pJCl was tested for homology with the E. coli plasmid R773, which encodes for arsenic resistance in that bacterium as well.

Through DNA-DNA hybridization the arsenic resistance determinants of R45 and R773 were compared. Under stringent hybridization conditions, R45 demonstrated DNA sequence …


Febrile Response And Activity In The Crayfish, Pacifasticus Leniusculus Trowbridgii, Kenneth A. Fletcher Feb 1988

Febrile Response And Activity In The Crayfish, Pacifasticus Leniusculus Trowbridgii, Kenneth A. Fletcher

Dissertations and Theses

Poikilothermic and endothermic animals demonstrate febrile response to infection with bacteria or to injection with endogenous pyrogen extract of Prostaglandin E1. Febrile response is measured in endotherms as a relative change in metabolically achieved body temperature and in poikilotherms as an increase in selected temperatures relative to previously established preferred temperatures. Final preferendum change with environmental factors or associated physiological states.

Crayfish Pacifasticus leniusculus trowbridgii were injected with 0.2 ml suspension of alcohol-killed gram-negative Aeromonas hydrophila bacteria in 0.9% saline. Injections were into the coxopodite of the cheliped. The crayfish were monitored in an aquatic thermal gradient by …


The Effect Of Cold Acclimation On The Temperature Preference Of The Goldfish, Carassius Auratus, And The Brown Bullhead, Ictalurus Nebulosus, Alfred Lord Nov 1987

The Effect Of Cold Acclimation On The Temperature Preference Of The Goldfish, Carassius Auratus, And The Brown Bullhead, Ictalurus Nebulosus, Alfred Lord

Dissertations and Theses

Two species of fish, Carassius auratus and Ictalurus nebulosus, were subjected to cold acclimation regimes. Acclimation temperatures were slowly lowered to 3°C, then held for a period of time. At various times during this regime, fish were taken out and allowed to spend time in a temperature gradient to determine their preferred temperatures. Carassius were left in the gradient just long enough to determine a measure of the acute temperature preference, while Ictalurus were left in the temperature gradient for longer periods of time to observe any changes that might occur as the fish adjusted to selected temperatures. In …


Decrease In Selected Temperature After Intracranial Dopamine Injections In Goldfish, Hercules Theodore Panayiotides-Djaferis Aug 1987

Decrease In Selected Temperature After Intracranial Dopamine Injections In Goldfish, Hercules Theodore Panayiotides-Djaferis

Dissertations and Theses

Goldfish (Carassius auratus) (40-80g) were injected with dopamine into the forebrain to study the possible involvement of this amine in central temperature regulation in these fish. Dopamine caused a decrease in selected temperature after injection into the rostral nucleus preopticus periventricularis (NPP). This effect was dependent on the dose of dopamine administered. Doses of 25, 50, 100 and 250 ng were used, injected in a volume of 0.2μ1. Injections in regions adjacent to the NPP elicited hypothermic effects only at the higher dosages. These effects were not consistent. Injections in caudal regions of the NPP elicited no effect. …


The Effect Of Body Temperature On Arteriovenous Oxygen Difference During Rest And Activity In The Toad, Bufo Marinus, Wayne Bryant Palioca Jul 1987

The Effect Of Body Temperature On Arteriovenous Oxygen Difference During Rest And Activity In The Toad, Bufo Marinus, Wayne Bryant Palioca

Dissertations and Theses

The relative contribution of arteriovenous oxygen (A-V O2) difference to thermally-induced and activity-induced changes in metabolic rate (VO2) were delineated in the toad, B. marinus. In conjunction, the influence of rest and activity, temperature, and removal of the pericardial sac on separation efficiency (Es) in the anuran ventricle was determined by direct measurement of arterial and venous percent oxygen saturation (% saturation), using a microsampling technique.


The Role Of Iron Nutrition In Regulating Patterns Of Photosynthesis And Nitrogen Metabolism In The Green Alga Scenedesmus Quadricauda, Dennis Raymond Ades Jan 1987

The Role Of Iron Nutrition In Regulating Patterns Of Photosynthesis And Nitrogen Metabolism In The Green Alga Scenedesmus Quadricauda, Dennis Raymond Ades

Dissertations and Theses

The influence of iron nutrition on patterns of photosynthetic behavior, nitrogen metabolism, and fixed-carbon allocation is reported for a common freshwater green alga. Cultures of Scenedesmus quadricauda were grown in Fraquil medium in which iron concentrations ranged from 1.0 μM to 0.01 μM (log 10-6 to 10-8 M, respectively). Carbon 14 and nitrogen uptake experiments were conducted at photosynthetically saturating and subsaturating photon flux densities.


Norepinephrine And Temperature Regulation In Goldfish, Lonnie Paul Wollmuth Jan 1987

Norepinephrine And Temperature Regulation In Goldfish, Lonnie Paul Wollmuth

Dissertations and Theses

Cannulae were implanted into forebrain loci of goldfish (Carassius auratus; 45-90 g) to determine (i) the effects and site of action of intracranial norepinephrine (NE) injections on behavioral thermoregulation and (ii) the mechanism and the types of adrenoreceptors involved in the thermoregulatory effect of NE. After 30 min in a thermal gradient, implanted fish were injected with norepinephrinebitartrate salt (2.5-500 ng NE) in a total volume of 0.2 ul (carrier was 0.7% NaCl). Injections of 5, 10, 25, and 50 ng NE into the anterior aspect of the nucleus preopticus periventricularis (NPP1 Peter and Gill 1975) led to consistent, dose-dependent …


Hemodynamics During Pregnancy: A Model For Cardiac Enlargement, David James Mendelson Jul 1986

Hemodynamics During Pregnancy: A Model For Cardiac Enlargement, David James Mendelson

Dissertations and Theses

Cardiac output increases by 30-50% during mammalian pregnancy. This increase is reflected by elevation in both heart rate and stroke volume. The primary mechanism of increased stroke volume appears to be cardiac enlargement, rather than increased preload, afterload, or contractility. Animal studies have shown that enlargement of the heart occurs prior to an increase in uterine blood flow during pregnancy and this type of enlargement can be mimicked by sex steroid administration.

Systemic vascular resistance greatly decreases during pregnancy and with sex steroid administration. It has been postulated that systemic vascular resistance may be a signal for heart size changes. …


Adsorption Of Aminopyridines To Phosphatidylserine Vesicles, Colin Wright May 1986

Adsorption Of Aminopyridines To Phosphatidylserine Vesicles, Colin Wright

Dissertations and Theses

Intrinsic association constants were determined for a series of aminopyridines on phosphatidylserine vesicles, through determination of electrophoretic mobility. The magnitudes of the constants were such that depolarization of the nerve terminal through binding to negative phospholipids seems unlikely to occur. The aminopyridines all had association constants between one half and one sixtieth the association constant of calcium. The aminopyridines probably block potassium channels in their enhancement of synaptic transmission.

An interesting correlation was noted in that the ranking of the aminopyridines in terms of their affinity for these lipids was approximately the same as the ranking of their enhancement of …


Effect Of Ethanol On Thermoregulation In The Goldfish Carassius Auratus, Candace Sharon O'Connor May 1986

Effect Of Ethanol On Thermoregulation In The Goldfish Carassius Auratus, Candace Sharon O'Connor

Dissertations and Theses

In an attempt to elucidate the mechanism by which ethanol affects vertebrate thermoregulation, the effect of ethanol on temperature selection was studied in the goldfish, Carassius auratus. Ethanol was administered to 10 to 15 g fish by mixing it in the water of a temperature gradient. The dose response curve was very steep between 0.5% (v/v) ethanol (no response) and 0.7% (significant lowering of selected temperature in treated fish). Fish were exposed to concentrations of ethanol as high as 1.7%, at which concentration most experimental fish lost their ability to swim upright in the water. At concentrations higher than …


The Effect Of Salinity On Habitat Selection Of Two Oregon Chiton Species (Katharina Tunicata And Mopalia Hindsii), David Carl Rostal Mar 1986

The Effect Of Salinity On Habitat Selection Of Two Oregon Chiton Species (Katharina Tunicata And Mopalia Hindsii), David Carl Rostal

Dissertations and Theses

Adult specimens of Katharina tunicata (mean weight = 10.23 grams) and Mopalia hindsii (mean weight = 10.90 grams) were tested for osmotic stress tolerance and oxygen consumption rates in a series of salinities (120%, 100%, 80%, 60%, and 40% seawater) at 11°C and 16L:8D photoperiod. K. tunicata and M. hindsii displayed similar trends in percent body weight variation and volume regulatory responses to osmotic stress. However, K. tunicata experienced a significantly higher percent body weight increase than did M. hindsii in response to hypo-osmotic conditions (80%, 60%, and 40% seawater). The mean rates of oxygen consumption per salinity for the …


Nitrogen Limitation Of Phytoplankton Growth In An Oligotrophic Lake, Michael Patrick Mulvey Jan 1986

Nitrogen Limitation Of Phytoplankton Growth In An Oligotrophic Lake, Michael Patrick Mulvey

Dissertations and Theses

Blue Lake, Jefferson County, Oregon, has high summer surface phosphorus concentrations (ca. 30 ug/l) yet is oligotrophic (summer Secchi depth is 11 to 16 meters). Nutrient enrichment experiments done with 1000 1 polyethylene enclosures indicate nitrate limitation of phytoplankton growth. Basin morphology may be an important factor in nutrient cycling in this lake. The lake has a maximum depth of 95.7 meters with an average depth of 42.7 meters. The lake basin has steep sides with only 4% of the lake bottom less than 3.3 meters deep. of recent volcanic origin.

In contrast, Suttle Lake, which is immediately downstream from …


Morphological Aspects Of Seedling Establishment In Four Temperate Region Phorandendron Spp., Beverlee M. Ruhland Jan 1986

Morphological Aspects Of Seedling Establishment In Four Temperate Region Phorandendron Spp., Beverlee M. Ruhland

Dissertations and Theses

Four species of Phoradendron were examined for seedling morphology: P. bolleanum subsp. densum (on Juniperus), P. californicum (on Prosopis), P. juniperinum subsp. juniperinum (on Juniperus, P. villosum subsp. villosum (on Quercus). The main species used in the study was P. juniperinum, using the other species for comparison. The initial shoot(s) of P. juniperinum may develop from the epicotyl of the developing seedling, from adventitious buds which arise from a cushion of tissue, termed the haustorial cushion, formed beneath the holdfast, or from both positions. When shoots arise only from adventitious buds the original seedling remains attached in a lateral position, …


The Contribution Of The Lymph Hearts In Compensation For Acute Hypovolemic Stress In The Toad Bufo Marinus, Mark Baustian Jan 1986

The Contribution Of The Lymph Hearts In Compensation For Acute Hypovolemic Stress In The Toad Bufo Marinus, Mark Baustian

Dissertations and Theses

Currently published data on the role of the lymphatic system in amphibians are inadequate and contradictory. Estimates of the rate of formation of lymph and the role of the lymph hearts in returning this fluid to the circulation are not based on actual volume determinations but rather estimates derived from changes in hematocrit using published values of plasma and blood volume. The lymph hearts are known to be vital to the maintenance of normal fluid compartment physiology and to increase their rate of activity during episodes of hypovolemic stress. Yet, significant redistribution of body fluids following hemorrage appears to occur …


Characterization Of A New Freshwater Methanogen, Methanogenium Wolfei Sp. Nov., Theodore B. Moore Jul 1985

Characterization Of A New Freshwater Methanogen, Methanogenium Wolfei Sp. Nov., Theodore B. Moore

Dissertations and Theses

A recently isolated freshwater methanogenium species, Methanogenium wolfei, is characterized. Cells were irregular cocci, measuring 1.5 to 2.0 micrometers in diameter. No motility was observed, but 1 to 2 flagella per cell were observed after staining with Gray's Flagella Stain. Colonies formed by this species were small, shiny, and green-brown in color. Formate or hydrogen plus carbon dioxide served as substrates for growth. The optimal temperature for growth was found to be 45 degrees centigrade with minimal growth below 30 degrees centigrade and above 55 degrees centigrade. The optimal pH for growth was determined to be 6.8. Optimal growth was …


Aspects Of Cardiovascular Oxygen Transport In Vertebrates, Michael Scott Hedrick May 1985

Aspects Of Cardiovascular Oxygen Transport In Vertebrates, Michael Scott Hedrick

Dissertations and Theses

The hematological and rheological characteristics of blood from a number of vertebrates was compared to assess possible species differences in blood viscosity that may influence cardiovascular oxygen transport. Nucleated red blood cells (RBCs) were more viscous (measured by cone-plate viscometry) in comparison with enucleate (mammalian) RBCs at hematocrits greater than 40% when measured at equivalent temperatures. The lower viscosity of enucleate RBCs is attributed to an enhanced deformability of enucleate cells in comparison to nucleated cells.


The Significance Of Hypovolemia In Dehydrational Death In Anurans, Peter Blair Kimmel Jan 1985

The Significance Of Hypovolemia In Dehydrational Death In Anurans, Peter Blair Kimmel

Dissertations and Theses

The importance of hypovolemia in dehydrational death was assessed in two anuran species. Xenopus laeyis, a species which experiences a significant reduction in circulating plasma volume with dehydration, was used to evaluate the role of sympathetic reflex compensation in hypovolemia. Adrenergic blockade with propranolol or phenoxybenzamine produced no significant reduction in dehydration tolerance in this species, although β-blockade with propranolol appeared to have a minor effect. The role of hypovolemic shock in the terminal circulatory collapse that precedes death in dehydrating anurans was investigated in the toad, Bufo marinus. The activity of lysosomal proteinases (cathepsins) was used as an indicator …


The Role Of Copper In The Apparent Aluminum Toxicity Of Aquatic Systems, Kirk Thomas O'Reilly Jan 1985

The Role Of Copper In The Apparent Aluminum Toxicity Of Aquatic Systems, Kirk Thomas O'Reilly

Dissertations and Theses

The effect of variations in aluminum and copper concentrations on the growth rate and enzyme activity of the green alga Scenedesmus quadricauda was investigated. The goal was to determine which chemical species control the biological parameters. The computer program MINEQL (Westal et al 1976) was used to estimate chemical speciation. In the prevalence of both metals, algal growth rate and alkaline phosphatase activity could be correlated to cupric ion activity. The activity of isolated bacterial alkaline phosphatase was found to be a function of both total copper concentration and cupric ion activity. A model was developed to predicted the effects …


Partial Purification And Characterization Of F₄₂₀-Dependent Nadp Reductase From Methanobrevibacter Smithii Strain De1, Scott D. Sheridan Jan 1985

Partial Purification And Characterization Of F₄₂₀-Dependent Nadp Reductase From Methanobrevibacter Smithii Strain De1, Scott D. Sheridan

Dissertations and Theses

The F420-dependent NADP reductase of Methanobrevibacter smithii has been partially purified employing a combination of affinity chromatography with Blue Sepharose (Cl-6B) and molecular sieve chromatography with Sephacryl S-200, The enzyme, which requires reduced F420 as an electron donor, has been purified over 145 fold with a recovery of 6%. A molecular weight of 120,00 for the native enzyme was determined by Sephacryl S-200 chromatography. A subunit molecular weight of 28,200 was determined by SDS-PAGE, indicating that the native enzyme is a tetramer. The optimal temperature for enzymatic activity was found to be 45°C, with a pH optimum …


The Analysis And Use Of Methodologies For The Study Of The Diets Of Long-Eared Owls From Three Environments In North Central Oregon, John M. Barss Jan 1985

The Analysis And Use Of Methodologies For The Study Of The Diets Of Long-Eared Owls From Three Environments In North Central Oregon, John M. Barss

Dissertations and Theses

Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity indices. The procedure was developed to provide a simple, easily replicated methodology for the study of pellets which also retains maximal data recorded from pellet analysis. A sample size of ten Long-eared Owl pellets was found adequate to calculate diversity indices with no significant loss of accuracy when compared to total pellets recovered from beneath a roosting site. Analysis of the total sample of pellets from a specific roost …


A Phylokaryotypic Evaluation Of The Genus Tursiops (Family Delphinidae), Melissa Kay Estes Jan 1985

A Phylokaryotypic Evaluation Of The Genus Tursiops (Family Delphinidae), Melissa Kay Estes

Dissertations and Theses

In an attempt to correlate genetic data with possible species delineation, this study investigates the presence of chromosomal variants between the North Atlantic bottle nose dolphin, Tursiops truncatus, and the North Pacific bottle nose dolphin, T. gilli. Blood samples were obtained from oceanaria in the United States. Location of capture was correlated with karyotype to compare chromosome morphology with geographic range.


Effects Of Dehydration On Hemoglobin Oxygen Affinity And Blood Cell Volume In Two Anurans, Andrew Christopher Zygmunt Aug 1984

Effects Of Dehydration On Hemoglobin Oxygen Affinity And Blood Cell Volume In Two Anurans, Andrew Christopher Zygmunt

Dissertations and Theses

Two aspects of possible adaptation in cardiovascular performance caused by increased plasma electrolytes were examined. Cells in anisotonic plasma may either act as osmometers or volume regulate. Blood flow rate is dependent upon cell viscosity, which in turn is a consequence of cell volume and membrane deform-ability. Cell volume changes which increase membrane deform-ability will thus potentially extend the limits of dehydration tolerance. It was found in R. catesbeiana and B. marinus that red blood cell is maintain constant volume during dehydration. Cells in vitro initially lose water, but then sodium, potassium and water move into the cell. Cell viscosity …