Download App

Organisms and Populations — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations5 Marks
Question
Comment on the growth curve given below.

✓

Answer

A population growing in a habitat with limited resources show initially a lag phase, followed by phases of acceleration and deceleration and finally an asymptote, when the population density reaches the carrying capacity. A’ plot of N in relation to time (t) results in a sigmoid curve. This type of population growth is called Verhulst-Pearl Logistic Growth and is described by the following equation:
$\frac{\text{dN}}{\text{dt}}=\text{rN}\Big(\frac{\text{K}-\text{N}}{\text{K}}\Big)\\\ \ \\\frac{\text{dN}}{\text{dt}}=\text{rN}\Big(1-\frac{\text{N}}{\text{K}}\Big)$
$\Big(1-\frac{\text{N}}{\text{K}}\Big)$ Environmental resistance.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "5 Marks Questions" from Organisms and Populations→Organisms and Populations — all question types→BIOLOGY STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Given below is a table showing the genotypes and the phenotypes of blood groups in the human population.
Genotype
Phenotype
W
Y
IB IO
Z
IA IB
O
X
O
  1. Identify the genotype Wand X, and the phenotype Y and Z.
  2. Name the pattern of inheritance exhibited by the phenotypes Y and Z in the table.
→
How have pest-resistant plants been produced using biotechnology? Explain.
→
Try to trace the various components of human evolution (hint: brain size and function, skeletal structure, dietary preference, etc.)
→
What is mycorrhiza? Write its main advantages.
→
Explain the various types of interactions between species.
→
In one family, the four children each have a different blood group. Their mother has blood group A and their father has blood group B. Work out a cross to explain how it is possible.
→
Complete the given table.
Name of the organism Product/ Enzyme/ Bioactive male cule
Aspergillus niger (i)
(ii) Ethanol
(iii) Cyclosporin-A
(iv) Acetic acid
Monascus purpureus (v)
Streptococcus (vi)
→
(i) Define contact inhibition.
(ii) Explain the difference between benign tumors
and malignant tumors.
(iii) Write any one cause of cancer.
→
Answer the following questions:
Draw a Graafian follicle and label antrum and secondary oocyte.
→
  1. Differentiate between: Autogamy, Geitonogamy and Xenogamy.
  2. Explain the events that occur during pollen-pistil interaction.
→