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

Gene recombinations, Which of the recombination process(transformation, con...

Which of the recombination process(transformation, conjugation and transduction) would be most likely to occur in the natural environment?

Define criteria for assessment of niacin status, Define Criteria for Assess...

Define Criteria for Assessment of Niacin Status? Niacin status can be monitored by daily urinary excretion of methylated metabolites, especially the ratio of the 2-pyridone to

What are the major terrestrial biomes, What are the major terrestrial biome...

What are the major terrestrial biomes? The main terrestrial biomes are: tundra, taigas (or boreal forest), tropical forests, temperate forests, grasslands and deserts.

How are the antibodies against the rh factor formed, How are the antibodies...

How are the antibodies against the Rh factor formed? Anti-Rh antibodies are made by humoral immune response. When an Rh- individual makes contact with the Rh factor this is rec

Hematology case study , would i be able to get help on these case study que...

would i be able to get help on these case study questions

Transplantation - clonal propagation, Transplantation - Clonal Propagation ...

Transplantation - Clonal Propagation The shoots or plantlets multiplied on a medium containing organic nutrients, show poor photosynthetic capability. Moreover, in these pla

Explain reproducibility of venricular ectopy, Q. Explain Reproducibility of...

Q. Explain Reproducibility of Venricular Ectopy ? Experimentally it has been shown that PVCs are frequently seen at the inception of acute ischaemia. Thus, exercise induced PVC

Write the meaning of life style modification, Write the meaning of Life Sty...

Write the meaning of Life Style Modification (LSM) Life style modification means diet control and doing exercises. Diet control and exercise should be planned on individual bas

PROTOZOA., WHAT ARE THE ADVANTAGES & THE DISADVANTAGES OF PROTOZOA?

WHAT ARE THE ADVANTAGES & THE DISADVANTAGES OF PROTOZOA?

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