<span>Although a star might look brighter than the Sun, a comparison of its absolute<span> magnitude might help prove that they have the same real brightness.
Absolute magnitude is a concept that compares the absolute brightness of celestial objects. The absolute magnitude of an object is defined as the apparent magnitude it would have if it were viewed at a standard distance of 10 parsecs (32.6 light-years) with no dimming of its light. The more luminous an object, the smaller the numerical value of its absolute magnitude.</span></span>
I hope this counts - cell wall! helps keep most materials out but allows specific materials to pass through. animal cells do not have a cell wall
- Xylem contains tracheids, vessels, xylem parenchyma and xylem fibre.
- Tracheids: They are elongated, tubular dead cells with tapering end walls.
- Vessels: These are also known as trachea. They are elongated, tubular dead cells. They are joined to each other by end to end forming a continuous pipe. The cells are thick and lignified.
- Xylem parenchyma: They are also called wood parenchyma. This is the only living tissue of xylem.
- Xylem fibre: They are dead cells with thick walled fibre.
- Phloem consists of sieve tubes, companion cells, phloem parenchyma and phloem fibres.
- Sieve tubes: These are elongated, tubular living cells arranged in a row, with their perforated end walls forming a sieve. They are non-nucleated. Their protoplasm are inter-connected through sieve plates. They possess vacuoles.
- Companion cell: They are elongated, lens-shaped cells containing dense cytoplasm and prominent nuclei. These cells maintain connection with sieve cells through pits.
- Phloem parenchyma: They are living thin walled parenchyma cells.
- Phloem fibre: They are also known as bast fibre. They are elongated fibre like sclerenchymatous dead cells with thick walls containing pits and interlocked ends. Phloem fibre are the only dead cells in phloem.
Hope you could get an idea from here.
Doubt clarification - use comment section.
The sets of alleles for each parent are Dm for the mother and DM, Dm, dM, and dm for the father. This information is fundamental for estimating genotype and allele frequencies in offspring.
<h3>What are alleles?</h3>
Alleles are gene variants for a given gene <em>locus</em>, diploid organisms inherit two alleles for each locus (one from each parent).
Gametes are germinal (haploid) cells that carry specific allele combinations.
The analysis of gamete combinations is fundamental to estimate genotypes and allele frequencies.
Learn more about alleles here:
brainly.com/question/3452155
