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Are variations inherited???????

Posted by Ruhani Arora 2 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Gagan 💖 2 years, 7 months ago

Hello Ruhi, Variation can be inherited and the variants formed by this are called germline variants. They are formed due the variation that occurred in the sperm or egg that resulted the variation. That variated gene 🧬 is also passed in progeny and there is also a chance of seeing the same in their next progeny (i.e. F2 progeny of the initial parents)

ANSWER

Name one fish like reptile that evolved from land reptile about 200 million years ago

Posted by Vipranshi Sharma 2 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Ruhani Arora 2 years, 7 months ago

Ichthyosaurs

ANSWER

From ch- Evolution How Industrial melanism in England is example of natural selection bcoz this was caused by polluted created by man not nature ??? Please solve my doubt

Posted by Ruhani Arora 2 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Human have innate immunity for protection against pathogen that may enter the gut along with the food. What are the two barriers that protect the body from such pathogens?

Posted by Sheetal Kumari 2 years, 7 months ago

CBSE > Class 12 > Biology

3 answers

Kishor Jhorar 2 years, 7 months ago

1.Physical barrier like skin and mucos 2.physiological barrier like tear and acid in stomach 3.cellular barrier like lymphocytes and monocytes

Dilshad Ahmad 2 years, 7 months ago

Cellular barrier and cytokine barrier

Dhaliwal Bhupi 2 years, 7 months ago

Saliva in mouth and hcl in stomach

ANSWER

Assertion (A): Embryos formed by in-vitro fertilization is used for embryo transfer in test tube baby program. Reason (R): Such transfer to assist those females who cannot conceive. a. Both A and R are true and R is the correct explanation of A. b. Both A and R are true but R is not the correct explanation of A. c. A is true but R is false.

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Madiha Siddiqui 2 years, 8 months ago

A

Gaurav Yadav 2 years, 8 months ago

A is true but r is false

ANSWER

Describe genetic code

Posted by Account Deleted 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Shanaya Rajput 2 years, 7 months ago

Genetic code is the sequence of nucleotide in DNA and RNA that determines the amino acid sequence of proteins.

ANSWER

Ovulation regulate by which hormone: (a) TSH (b) ACTH (c) ADH (d) FSH and LH

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

5 answers

Preeti Dabral 2 years, 8 months ago

Luteinizing hormone (LH): This hormone stimulates ovulation in women and testosterone production in men.

Kishor Jhorar 2 years, 7 months ago

Option (d)

Dhaliwal Bhupi 2 years, 7 months ago

D

Divya. Kumari 2 years, 8 months ago

Lutenising hormone

Vaidehi Singh Bhadoriya 2 years, 8 months ago

LH

ANSWER

Which one of the following is the most likely root cause why menstruation is not taking place in regularly cycling human female? (a) Maintenance of the hypertrophical endometrial lining (b) Maintenance of high concentration of ***- hormones in the blood stream (c) Retention of well-developed corpus luteum (d) Fertilisation of the ovum

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Dhaliwal Bhupi 2 years, 7 months ago

D

Vaidehi Singh Bhadoriya 2 years, 8 months ago

b) Maintenance of high concentration of hormones in blood stream

ANSWER

What are the various male accessory glands? Give their function.

Posted by Manish Singh 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Akshit Dogra 2 years, 3 months ago

The male accsory glands include des the pair of seminal vesicle and prostate gland them the last bulbourethral gland or cowpers gland * Seminal vesicle makes the 60% of the semen and do contains fructose(gives energy to sperms) , fibrinogen ( Create semen cogulated) inositol(contraction in female genital track)etc *Prostate gland holds 30% of the semen and adds calcium, phosphate, profibrinolysin and the citrate (gives acidic ph to semen ) * Cowpers gland It provides lubricant to *****.

Anjan Karthi 2 years, 8 months ago

The various male accessory glands include the prostrate gland, the seminal vesicles and the bulbourethral (Cowper's) gland. The primary function of the accessory gland products is to facilitate sperm transfer to the female. The function of seminal vesicle is the production of the fluid that mixes with the sperm and makes up a significant percentage of semen. The prostate gland helps in the ejaculation of the sperm. Further, the bulbourethral gland provides nutrition and additional lubrication to the sperms.

ANSWER

To estimate the amount of fats in dry fruits

Posted by Janiz Jafica 2 years, 8 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

What is oesophagus

Posted by Satish Kumar 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Anjan Karthi 2 years, 8 months ago

It's a long tube connecting the buccal cavity (MOUTH) to the stomach. It's main characteristic feature is it's muscles (from outside) with peristaltic property. These ensure smooth movement of bolus (processed food from buccal cavity) to the stomach.

ANSWER

Which of the following statements about sporopollenin is false? (a) Exine is made up of sporopollenin (b) It is one of the most resistant organic material known (c) No enzyme can degrade sporopollenin (d) Exine has prominent apertures called germ pores where sporopollenin is present ( explain in detail)

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

3 answers

Dilshad Ahmad 2 years, 7 months ago

D

Vaidehi Singh Bhadoriya 2 years, 8 months ago

Answer - d) because sporopollenin is absent on germ pores

Anjan Karthi 2 years, 8 months ago

Correct option is C) Sporopollenin is a major component of the tough outer walls called as exines in plant pores and pollen grains. They are not specified to germ pore alone, but is the chemical which forms the overall structural component.

ANSWER

Explain the development of human embryo with diagrams

Posted by Manish Singh 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Bhumika Tyagi 2 years, 8 months ago

The development of human development...is defined as very crucial

ANSWER

Draw the sketch an anther or label the parts

Posted by Ajitha Kumari 2 years, 8 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Polar nuclei are situated in the central cell - (a) Below the egg apparatus (b) Above the egg apparais c) Below the antipodals (d) All of the above

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Anjan Karthi 2 years, 8 months ago

Supposed to be both (b) and (c). Considering the case of anatropous ovules (that we are currently studying), the micropylar end of the embryo sac is found towards the bottom of the ovary and the chalazal pole is found towards the upper part of the ovary. In that case, the one at the top of the embryo sac will be the antipodals, followed by the central cell and finally the egg apparatus.

Ananth Krishna H 2 years, 8 months ago

C

ANSWER

Secondary oocyte retains bulk nutrient rich plasm of the primary oocyte. Can you think of any advantage for this?

Posted by Harsimran Kaura 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Preeti Dabral 2 years, 8 months ago

The secondary oocyte retains the bulk of the nutrient-rich cytoplasm of the primary oocyte because the secondary oocyte further develops into ovum that undergoes fertilization and formation of the zygote where the nutrition in bulk is required for healthy development and growth.

ANSWER

Site retains bulk of the nutrient is cytoplasm of the primary oocyte what is the advantage of this??

Posted by Harsimran Kaura 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Preeti Dabral 2 years, 8 months ago

The secondary oocyte retains the bulk of the nutrient-rich cytoplasm of the primary oocyte because the secondary oocyte further develops into ovum that undergoes fertilization and formation of the zygote where the nutrition in bulk is required for healthy development and growth.

ANSWER

How many wild life sanctuary in the world

Posted by Shivam Pandit 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Preeti Dabral 2 years, 8 months ago

The western part of Karnataka is included in the western ghats as a biodiversity spot. The state has over 20 famous wildlife sanctuaries for now.

Anjan Karthi 2 years, 8 months ago

We need not learn about the world. If you wish to know about those in India, there are 448 wildlife sanctuaries.

ANSWER

What's is megaspore

Posted by Yaditi Nishad 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Arifa Noor 2 years, 8 months ago

Megaspores are produced by meiosis in megaspores mother cell

ANSWER

What is double fertilisation

Posted by Jishu Kumar 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Tanisha Upadhayay 2 years, 8 months ago

Sangamy and triple fission together constitute double fertilisation

ANSWER

Which one of the following is not a major characteristic feature of biodiversity hot spots? (a) Large number of species (b) Abundance of endemic species (c) Large number of exotic species (d) Destruction of habitat

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Sanjana Barik 2 years, 8 months ago

D

Riya Joshi 2 years, 8 months ago

A

ANSWER

Wildlife safari park is for plants or animals??

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

3 answers

Anjan Karthi 2 years, 8 months ago

Well she is true. In wildlife safari parks, threatened species are conserved in a particular area, other than their natural habitat. People are permitted to visit these parks to see the animals and plants conserved there. It's ex - situ conservation and the answer lies there itself, ex-situ is wherein the species is conserved outside the habitat providing the necessary conditions it required in the habitat. So, wild animals do need the presence of trees and grasses and all that- or else, they may feel offended, right? And, plants are where animals are, too.

Ruhani Arora 2 years, 8 months ago

I mean to ask it's for both or animals only? Coz in one video I studied that it's for both but I am little confused

Sneha Chaudhary 2 years, 8 months ago

Ofcourse for animals

ANSWER

Foetal ejaction reflex refers to?

Posted by Qazim Khan 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Tanisha Upadhayay 2 years, 8 months ago

Release of oxitocin as per required

Tanisha Upadhayay 2 years, 8 months ago

Production of oxitocin for parturation

ANSWER

If slope of a regression line (z) is increasing then species richness will _________ ( Increase or decrease)

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Sanjana Barik 2 years, 8 months ago

Increase. Because, slope reflects dependency on Area therefore, more is the area more will be the species

ANSWER

Project on Study of environmental condition on seed cultivation

Posted by Naveen Priya Naveen Priya 2 years, 8 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

How is humus formed? Mention any three characteristics of humus.

Posted by Adarsh Kumar Tiwari 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Anjan Karthi 2 years, 8 months ago

As a result of the catabolic action of saprophytic microbes on fragmented detritus, dark, moist and amorphous matter known as humus gets accumulated over the soil layers. This material is composed of higher nutrient content than normal soil and makes nutrients available to plants in absorbable forms. Following are the three main characteristics of humus :- It binds the soil together, and prevent soil erosion. Humus content affects the color, texture, and structure of the soil. Soil with rich humus tends to be dark with a loamy texture.

ANSWER

The size of the population tells us a lot about its status in the (a) Environment (b) ***-ratio (c) Age pyramid (d) Habitat

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Anjan Karthi 2 years, 8 months ago

(c) Age pyramid. (Provides a graphical representation of the distribution of pre-reproductive, reproductive and post-reproductive individuals in the population. If the number of pre- reproductive individuals is more, the population is said to be a growing population. If the number of pre-reproductive and reproductive individuals are almost equal, the population is stabilised but not growing. If the number of pre-reproductive individuals is low, then the population is said to be declining.

ANSWER

All organisms cannot tolerate a wide range of salinities. ( True / False )

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Qazim Khan 2 years, 8 months ago

False.

Anjan Karthi 2 years, 8 months ago

False. (Exp = Majority of organisms can tolerate only a narrow range of salinity and these are called stenohaline organisms. The remaining organisms, which include halophiles and marshy microbes, can tolerate a good and wide range of salinity and these are called euryhaline organisms.)

ANSWER

Many fresh water animals cannot lie for long in sea water due to the salinity of sea water. ( True or False )??

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Anjan Karthi 2 years, 8 months ago

True. (Exp = Most freshwater organisms are stenohaline and are not much used to significantly wide ranges of salinities. Consequently, staying for long in the salty sea water can disturb the osmotic balance in their body, as a result of which they won't survive for much long.)

ANSWER

Discuss the various types of positive interactions between species? Saari websites pe iske answer me sirf 2 type hai mutualism and commensalism but isme parasite ya fir predation kyu nhi hai?? Kyuki usme bhi toh 1 species ko benefit hota hai

Posted by Ruhani Arora 2 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Anjan Karthi 2 years, 8 months ago

The net nature of the interaction is what matters here. In predation and parasitism, it is always (+,-) where one organism makes benefit out of the other organism in a way that it causes harm or negatively affect the latter. So, net effect is negative, actually. The various types of positive interactions, therefore, would be mutualism and commensalism (mainly).

ANSWER

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