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3 years ago

Primary succession takes much longer than secondary succession because it involves _________

Biology

2 answers:

olga_2 [115]3 years ago

6 0

Answer:

Rocks or lava

Explanation:

In 1° succession there is no soil.. And the process of soil formation take very long time.

In 1° succession rocks or lava is present and lichens, soil erosion, wheathring of rocks helps in soil formation.

borishaifa [10]3 years ago

5 0

Primary succession takes much longer than secondary succession because it involves time for weathering of rock and development of the soil horizons.

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Prairie dogs are rodents that live in colonies. Black-tailed prairie dog (Cynomys ludovicianus) colonies typically have around 1

Tresset [83]

Population density is the aspect of population ecology of the black-tailed prairie dog does this statement describe.

Explanation:

Population density is the number of organisms are there in per unit area. It is used to measure geographical area occupied by organisms and its statistics.

In population ecology the structure, dynamics and contribution of population of species is studied. The idea of species distribution is studied in it.

The population density determines the number of species or members of particular population are present is a particular area.

An area of low density population will have more resources and more area per organism and less competition for resources and vice versa for high density population.

Prairie dogs have 12 adults per hectare of area this tells the population density of the rodents.

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3 years ago

What do you think selectively permeable means?

enot [183]

Answer:

B. The membrane lets certain substances move across it freely, while others must move through a “gate”.

Explanation:

Selective permeability is a property of cellular membranes that only allows certain molecules to enter or exit the cell. This is important for the cell to maintain its internal order irrespective of the changes to the environment. For example, water, ions, glucose and carbon dioxide may need to be imported or exported from the cell depending on its metabolic activity. Similarly, signaling molecules may need to enter the cell and proteins may need to be released into the extracellular matrix. The presence of a selectively permeable membrane allows the cell to exercise control over the quantum, timing and rate of movement of these molecules.

3 0

3 years ago

Read 2 more answers

Two autosomal genes, J and K, are 60 map units apart. You perform the following testcross: J K / j k x j k / j k. At what freque

Dmitry [639]

Answer:

J K / j k = 20%

j k / j k = 20%

J k / j k = 30%

j K / j k = 30%

Explanation:

To calculate the recombination frequency, we have to know that 1% of recombinations = 1 map unit = 1cm. And that the maximum recombination frequency is always 50%.

The map unit is the distance between the pair of genes for which every 100 meiotic products, one of them results in a recombinant one.

So, en the exposed example:

J and K are autosomal genes

J and K are separated by 60 M.U.

60 M.U. means that there is 60% of recombination.

Cross) J K / j k x j k / j k

Gametes) JK Parental jk, jk, jk, jk

jk Parental

Jk Recombinant

jK Recombinant

One map unit equals 1% of recombination frequency. This means that every 100 meiotic products, one of them is a recombinant one.

1 M.U. -------------- 1% recombination

60 M.U. ------------ 60% recombination

30% Jk + 30% jK

100 M.U. - 60 M.U. = 40 M.U.

40M.U.--------------40 % Parental (Not recombinant)

20% JK + 20% jk

Punnet Square) JK jk Jk jK

jk JK/jk jk/jk Jk/jk jK/jk

J K / j k = 20%

j k / j k = 20%

J k / j k = 30%

j K / j k = 30%

3 0

3 years ago

A pregnant woman found a large variety of microbes that can be vertically transmitted. She is making a list for her doctor to as

natta225 [31]

Answer:

Hyphae: Cell filaments,mostly septate

Mycelium: Mass of hyphae

Molds: mostly filamentous, Yeasts: non-filamentous,unicellular fungi

Budding yeasts divide asymmetrically.

Dimorphic fungi: yeast-like at 37°C, mold-like at 25°C.

Fungal spores are reproductive spores (unlike bacterial spores). Used to differentiate fungi.

Growth in acidic, low-moisture, high osmotic pressure environments.

The thallus (body) of a mold or fleshy fungus consists of long filaments of cells joined together; these filaments are called hyphae. Hyphae can grow to immense proportions. The hyphae of a single fungus in Oregon extend across 3.5 miles.

In most molds, the hyphae contain cross-walls called septa (singular: septum), which divide them into distinct, uninucleate (one-nucleus) cell-like units. These hyphae are called septate hyphae. In a few classes of fungi, the hyphae contain no septa and appear as long, continuous cells with many nuclei. These are called coenocytic hyphae. Even in fungi with septate hyphae, there are usually openings in the septa that make the cytoplasm of adjacent "cells" continuous; these fungi are actually coenocytic organisms, too.

Mycelium a mass of long filaments of cells that bring and intertwine, typically found in molds.

Explanation:

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3 years ago

How could different nucleotide sequences result in the same amino acid<br> sequences?

vladimir1956 [14]

Answer:

There is more than one codon that can specify most amino acids, therefore you never know which one was used for a particular protein, unless you can look at the DNA or RNA sequence.

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2 years ago