Sigmoid growth curve, Biology

Assignment Help:

GROWTH CURVES -

S-shaped or sigmoid -

Described by Verhuhst in 1839.

It shows 5 phases -

(i) Lag phase

(ii) Positive acceleration phase

(iii) Exponential phase

(iv) Negetive accesleration phase

(v) Stationary

1480_sigmoid growth curve.png

1.       Lag phase -

  • Early stage of curve.
  • When new individuals come in new environment so minimum growth occur in these phase.
  • It is due to absence of new resources.
  • It is due to lack of adaptations.

2.       Positive acceleration phase -

  • Growth rate is increased.
  • Birth rate increases.
  • Death rate is minimum.

3.       Exponential phase -

  • Individuals become adaptated.
  • Rapid growth occur.
  • Birth rate very high.
  • Death rate very low.

4.       Negetive accesleration phase -

  • Growth rate decreases.
  • Available sources become limited.

5.       Stationary -

  • Resources are limited.
  • Birth rate is equal to death rate.
  • So growth rate is zero.
  • In the growth curve of bacteria after stationary phase growth decreases due to unavailability of resources.

2258_sigmoid growth curve1.png

If semi log curve is drawn for bacteria curve is in the form of straight line.

897_sigmoid growth curve2.png


Related Discussions:- Sigmoid growth curve

Write the blood sugar in normal range and range in diabetes, Q. Write the b...

Q. Write the blood sugar in normal range and range in diabetes? Normal           Diabetes mellitus >126 mg / dl >200 mg / dl

Endosperm with lateral haustoria, Endosperm with Lateral Haustoria In...

Endosperm with Lateral Haustoria In Monochoria, in which the endosperm development is of helobial type, the haustorium is neither chalazal nor micropylar but lateral. The cha

What is the condition for mendels second law to be valid, What is the condi...

What is the condition for Mendel's second law to be valid? Mendel's second law is only valid for genes located in dissimilar chromosomes. For genes situated in the same chromos

Applications of transgenic animals, A pp l i c a tion s of transgeni...

A pp l i c a tion s of transgenic animals Current applications of gene transfer in farm animals include the improvement of product quality and quantity, disease resistan

Hemerythrins - respiratory pigments, Hemerythrins - Respiratory Pigments ...

Hemerythrins - Respiratory Pigments The Hemerythrins are rather rare. They take place in some animals belonging to the minor phyla like the sipunculid worms, some brachiopods,

What is the nature of monosaccharides, What is the Nature of Monosaccharide...

What is the Nature of Monosaccharides? Monosaccharides are colourless, crystalline substances which are soluble in water but insoluble in non polar solvents. Monosaccharides ca

Low output versus high output heart failure, Most forms of cardiac diseases...

Most forms of cardiac diseases, like hypertension, valvular diseases and coronary artery diseases manifest as low output heart failure. Systemic vasoconstriction with cold extremit

What is the importance of biotin, What is the Importance of biotin Biot...

What is the Importance of biotin Biotin is involved in a number of important metabolic reactions, probably as coenzymes. Deficiency symptoms are manifest as degenerative cha

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd