Long Answer Type(a) Mention the important features of the Neanderthal man.
(b) What are homologous organs? How do they help in providing evidence for organic evolution?
a. Describe the different types of vascular bundles.
b. Give three anatomical differences between a monocot root and a dicot root.
c. Explain the effect of light and temperature on photosynthesis.
(a) Explain the transpiration pull theory for ascent of sap.
(b) Explain the process of spermatogenesis in humans.
(c) Define the following:
(i) Placentation
(ii) Parthenocarpy
(iii) Diffusion
(a) Why are xylem and phloem classified as complex tissues? Describe the structure of phloem.
(b) Describe the ultra-structure of chloroplast.
(c) State three functions of the placenta.
(a) Describe the experiment performed by Griffith. What conclusions did he infer from his observations?
(b) What is artificial insemination? Mention two ways in which it is useful in breeding of dairy animals.
(c) What is single cell protein? Give its source and significance.
(a) How did Hershey and Chase prove that DNA is the genetic material?
(b) Give one main application of each of the following:
(i) MRI
(ii) Ultrasound
(iii) ECG
(c) Explain the role of stem cells in medical treatment.
a.
(a) Hershey and Chase conducted experiment on T2 phage, a parasite on common bacterium Escherichia coli. Some T2 phages were grown in cultures of bacteria containing radioactive S(35), whereas remaining T2 phages were grown in cultures of bacteria containing radioactive P(32). S35 was incorporated in the protein coat whereas P32 was incorporated in the DNA of T2 phage. These two types of radioactive phages were made to infect Escherichia coli in two separate samples.
The phages grown in S35 did not transmit their radioactivity to their daughter phages. Whereas the phages P32 pass their radioactivity to the daughter phage particle.
This proved that only DNA was passed on from one generation of T2 to the next.
(i) MRI :
In the examination of brain and spinal cord musculo skeletal disorders, blood flow. In the examination of cancerous bone, pelvic, urinary bladder, joints, vertebral column and cancerous growth in liver and kidney, heart and brain strokes.
(ii) Ultrasound is used in the diagnosis of kidney and gall bladder stones, liver diseases, diseases of ovaries, uterus, etc.
(iii) ECG to anayse the rate and rhythm of atria and ventricles and hence the condition of cardiac muscles of different chambers of heart
(c) Role of stem cells in medical treatment: treatment of genetic disorders/blood cancers.
(a) Write short notes on:
(i) Multiple Alleles
(ii) Artificial measures to control population
(b) What complications will arise if the blood of an Rh positive person is transfused to an Rh negative person and vice versa?
(c) State any three goals of the human genome project.
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