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

Diastolic pressure, Palpate the radial or brachial artery pulsation while i...

Palpate the radial or brachial artery pulsation while inflating the cuff to a level of 30 mm Hg above the point at which the brachial or radial artery pulsation disappears. Reinfla

Pethidine and methadone, PETHIDIN E - Meperidine hydrochloride. ...

PETHIDIN E - Meperidine hydrochloride. Widely used as narcotic analgesic. It has local anesthetic action. METHADON E - It is an orally effective anal

How identical proteins form, Are proteins with the same number of each diff...

Are proteins with the same number of each different amino acid that form them necessarily identical proteins? Even if many proteins have the similar number of each dissimilar a

Why physical activity is important for weight loss, Why Physical Activity i...

Why Physical Activity is important for weight loss? You are already aware that exercise plays an important role in initiating and sustaining weight loss along with dietary and

What is cyanosis, What is Cyanosis ? Cyanosis: Cyanosis may be peripher...

What is Cyanosis ? Cyanosis: Cyanosis may be peripheral or central. Peripheral cyanosis almost exclusively involves lips and extremities. Normal neonates may have bluish extrem

Root - plant water relation, Root - Plant Water Relation Root system i...

Root - Plant Water Relation Root system is directly related to the absorption of water and its growth under field conditions is very much influenced by soil. In dry land agric

Demand for health care in the presence of health insurance, Normal 0 ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Explain the effect on vitamins of the human milk, Explain the effect on Vit...

Explain the effect on Vitamins of the human milk? Although there are inter-individual variations in vitamin concentrations, diet and drug use by individual women influences vit

What are the types of plant geotropisms, What are the types of plant geotro...

What are the types of plant geotropisms? Why do the stem and the root present opposite geotropisms? The parts of geotropisms are the positive geotropism, that in which the plan

Explain about the cardiovascular disease and stroke, Explain the Cardiovasc...

Explain the Cardiovascular disease and stroke? Obesity may be an independent risk factor for coronary heart disease (CHD) with the degree of obesity being directly proportional

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