Answer:
<u>3) Uncontrolled cell division occurred as a result of gene mutations</u>
<u />
Explanation:
Spontaneous modifications within the genome may occur during the process of cell division. When copies of the DNA inside the cell are made, these mutations cause errors; and can include small single nucleotide polymorphisms, and large scale additions or deletions across multiple genes.
Some, like somatic mutations, exist only inside vegetative (body) cells, that cannot be passed onto offspring. This is caused by several factors like
- UV radiation,
- chemical mutagens,
- infective agents
UV radiation damages strands of DNA, by causing dimers to form; here, consecutive nucleotide bases covalently bond instead of those on the complementary strand. This conformational change causes errors in DNA proofreading and repair mechanisms where bases are not well-incorporated into the strand- tumors (clumps of uncontrolled cell growth) may form, resulting in melanoma, a type of skin cancer.
Answer:
The correct answer would be reproduction.
Single-celled organisms usually reproduce asexually with the help of cell division.
Asexual reproduction is a type of reproduction which takes place without the fusion of gametes and hence required only one parent.
Various types of asexual reproduction are fission (binary or multiple), budding, fragmentation, vegetative propagation etc.
Unicellular organism usually divide by fission either binary or multiple.
In binary fission, a parent cell divide into two equal sized daughter cells such as observed in bacteria.
In multiple fission, a parent cell divides into multiple daughter cells as observed in multiple fission of sporozoans etc. During this, parental nucleus divides several times with the help of mitosis without cytokinesis which produces several nuclei within a parent cell. The cytokinesis then takes place which results in separation and production of multiple daughter cells.
Per calendar year (365 days) there are 31536000 seconds
Answer:
a. Capsules
Explanation:
Capsules are features of bacteria cell. A bacterial capsule is a structure made up of polysaccharides and proteins that functions to prevent pathogenic bacteria from getting engulfed (phagocytosid) by the immune system (white blood cell).
According to this question, capsules are bacteria structure that aid in antiphagocytosis of the bacteria. Gjj
The fish are eaten by ducks. Ducks cannot really swallow preys that are too big for their throats. They usually swallow organisms that are a lot smaller than fishes. because they do not have the capacity to bite and chew their preys.
