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3 years ago

What should you use to secure a slide?

1 answer:

4 0

You should always, and I mean always, use a coverslip on your slide. Without it, the contents on it would slip off and there'd be a big mess.

For extra security:

Always make sure your stage clips are working! :)

I hope I helped! :)

You might be interested in

An adolescent with pneumonia is admitted to the pediatric unit. after his parents leave the unit for the evening, he tells the n

RideAnS [48]

The nurse may say something along the lines of "The order will be submitted to your physician. Your parents will not know." It is only a simple test to see whether the boy has contracted the Human Immuno-Deficiency virus, and thus is not anything that requires interference on the parents' part, which may bring embarrassment on the adolescent. The nurse is practicing general ethics and her moral code here.

3 0

3 years ago

Determine whether each statement describes mitosis, meiosis, or both mitosis and meiosis.

svp [43]

Occurs in organisms that sexually reproduce ==> Occurs in meosis.

Meiosis is a type of gamete-specific nuclear division.

Meiosis occurs during spermatogenesis and oogenesis (egg formation in women).

In order for the number of chromosomes, characteristic of the species, to be conserved, it is necessary that before the encounter, the number of chromosomes of each of the reproductive cells be divided by two.

The reduction in the number of chromosomes takes place during the phenomenon called "meiosis".

Occurs during growth and development ==> It concerns mitosis.

Mitosis will ensure the good fulfillment of several phenomena:

. embryonic development,

. the general growth of organisms from birth to adult size,

. continued growth of certain organisms and / or organs; for example, trees, hair, teeth in ruminants, nails, ...

The DNA is replicated ==> concern both mitosis and meiosis.

The cell cycle of eukaryotic cells is as follows:

• Interphase (normal functions, DNA replication)

G1 - growth / cellular activity

S - DNA synthesis / replication

G2 - preparation for division

• Phase M (cell division): which consists of either mitosis or meiosis, depending on cell types.

• Cytocinesis (cytoplasmic division).

So whether it is mitosis or meiosis, both are preceded by a replication of the genetic material (DNA)

Occurs in all organisms ==> concern both mitosis and meiosis.

An organism is a set of elements that make up a functional structure.

In biology, the term organism designates a living being as it is organized, that is to say composed of different organs or organelles forming a coherent whole (as opposed to micro-organisms).

All multicellular organisms have sexual reproduction, so their cells are systematically mitosis and meiosis.

We exclude microorganisms of which a very small part of them have asexual reproduction.

The number of chromosomes remains the same : concerns only mitosis.

During mitosis, the human cell has 2n monochromatid chromosomes. In phase S consists of a doubling of the amount of DNA indeed, and the cells then have 2n chromosomes bichromatidiens. In the metaphase of mitosis, the chromosomes of the mother cell are arranged on a "metaphase plate", then split in 2-chromosomes, but monochromatids, during anaphase. Each daughter cell therefore has 2n monochromatid chromosomes.

The number of chromosomes reduces by half ==> Concerns only meiosis

Meiosis unfolds in two stages:

* The first meiotic division is called reductional because it allows to pass from 2n double chromosomes to n double chromosomes.

* The second is called equational because it preserves the number of chromosomes: one passes from n double chromosomes to n simple chromosomes.

Meiosis thus allows the formation of 4 haploid daughter cells (or gametes).

In humans, a normal cell contains 2n = 46 chromosomes (thus 23 pairs) while a gamete contains n = 23 chromosomes in two divisions).

3 0

3 years ago

Read 2 more answers

Burning wood into ash is an example of which kind of change?

mrs_skeptik [129]

It’s chemical I’m pretty sure

7 0

4 years ago

Read 2 more answers

Without the rough er cells would ?

Degger [83]

There are two basic types of ER. Both rough ER and smooth ER have the same types of membranes but they have different shapes. Rough ER looks like sheets or disks of bumpy membranes while smooth ER looks more like tubes. Rough ER is called rough because it has ribosomes attached to its surface.

The double membranes of smooth and rough ER form sacs called cisternae. Protein molecules are synthesized and collected in the cisternal space/lumen. When enough proteins have been synthesized, they collect and are pinched off in vesicles. The vesicles often move to the Golgi apparatus for additional protein packaging and distribution. 

Smooth ER (SER) acts as a storage organelle. It is important in the creation and storage of lipids and steroids. Steroids are a type of ringed organic molecule used for many purposes in an organism. They are not always about building the muscle mass of a weight lifter. Cells in your body that release oils also have more SER than most cells. 

God Bless:)

6 0

3 years ago

Suppose we were successful in identifying 12 mutants using a screen for identifying conditional mutants of S. cerevisiae in whic

Marina CMI [18]

Answer:

Each mutant would be mated to wild type and to every other mutant to create diploid strains. The diploids would be assayed for growth at permissive and restrictive temperature. Diploids formed by mating a mutant to a wild type that can grow at restrictive temperatures identify the mutation as recessive. Only recessive mutations can be studied using complementation analysis. Diploids formed by mating two recessive mutants identify mutations in the same gene if the diploid cannot grow at restrictive temperature (non-complementation), and they identify mutations in different genes if the diploids can grow at restrictive temperature (complementation).

Explanation:

Recessive mutations are those whose phenotypic effects are only visible in homo-zygous individuals. Moreover, a complementation test is a genetic technique used to determine if two different mutations associated with a phenotype colocalize in the same locus (i.e., they are alleles of the same gene) or affect two different loci. In diploid (2n) organisms, this test is performed by crossing two homo-zygous recessive mutants and then observing whether offspring have the wild-type phenotype. When two different recessive mutations localize in different loci, they can be considered as 'complementary' since the heterozygote condition may rescue the function lost in homo-zygous recessive mutants. In consequence, when two recessive mutations are combined in the same genetic background (i.e., in the same individual) and they produce the same phenotype, it is possible to determine that both mutations are alleles of the same gene/locus.

5 0

3 years ago