Objection of cell theory, Biology

Assignment Help:

OBJECTION OF CELL THEORY (REASONS OF DISCARTION)

(i)       Living organism are composed of various types of cells and their product but members of monera & protista don't have a cellular organisation, they have protoplasmic grade & organization.

Cell theory is not applicable on viroids, Viruses, Prions.

(ii)      In multicellular organism one type of cell perform one type of function. It doesn't perform all vital activities.

(iii)         Gene is the hereditary unit of life according to modern view - Physical unit of life = Gene

Chemical unit of life = DNA

(iv)      In plants many dead cells are present, which also have specific function. Vessels and Tracheids of Xylem are dead cells but helps in conduction of water & minerals. In human beings, cells of stratum corneum (outermost layer of skin) are dead & helps in protection.

(v)      It was not discarded but modified by Nageli, he just added "through cell division" while omnis cellula e cellula means that cells arise inside the cell. According to Karl nageli "new syncytes arise from division of pre-existing cells".


Related Discussions:- Objection of cell theory

Determine the organs of female reproductive system, What are the anatomical...

What are the anatomical relationships between the organs of the female reproductive system from the external vulva to the ovaries? The external female genitalia is called the v

Why two atoms always represent the same element, Two atoms always represent...

Two atoms always represent the same element if they have. A) the same number of particles in the nucleus. B) The same number of electrons. C) The same number of shells. D) The same

Blood protozoan and ricketsial diseases - babesiosis, B a b e s i o ...

B a b e s i o s i s It is also known as red water disease or cattle tick fever and is characterized by fever, intravascular haemolysis, acute anaemia and haemoglobinur

Why meat and poultry are important for human body, Why Meat and Poultry are...

Why Meat and Poultry are important for human body? Meat and poultry are rich sources of proteins of high biological value. They do not contain carbohydrates. All

Explain about the proteins, Explain about the Proteins? The term protei...

Explain about the Proteins? The term protein (Greek: proleuo- to occupy first place) was first suggested by Berzelius to describe the complex organic nitrogenous substances fou

Operculum - seed appendages, Operculum - Seed Appendages The term oper...

Operculum - Seed Appendages The term operculum is applied to a plug-like structure formed in the micropylar portion of the seed by proliferation of cells at the tip of the inn

Explain which provides barrier to the movement of molecules, In a plasma me...

In a plasma membrane, which of the below provides a general barrier to the movement of molecules? a) Lipids b) Proteins c) Carbohydrates d) all of these Answer: a

Transport with the help of membrane protein, Transport with the Help of Mem...

Transport with the Help of Membrane Protein Even though, the lipid bilayers do not permit the entry of polar molecules such as ions, sugars, amino acids, nucleotides and cell

Copulation and fertilisation in hermaphrodites, Copulation and Fertilisatio...

Copulation and Fertilisation in Hermaphrodites Copulation between hermaphrodites is common. Flatworms possess a cirrus and penis that is inserted into the uterine vaginal ope

What are the five human digestive secretions, What are the five human diges...

What are the five human digestive secretions? Which of them is the only one that does not contain digestive enzymes? The human digestive secretions such as: saliva, gastric jui

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