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3 years ago

what is the only characteristic currently known to be unique to all dinosaurs and why is it important

1 answer:

4 0

There are multiple characteristic that all dinosaurs shared. Some of the synapomorphies include:
- Vertebrates; skeletons with back bones that surrounds a nerve cord.
- Amniotes; specially adapted for life on dry land.
- Diapsids; two holes located above and behind the eye sockets on each side of the skull.
- Archosaurs; antrobital ferestra, a hole between the nasal hole and the eye socket hole.
But still all of this doesn't separate them from all others, what is unique to them is that all of the 'true dinosaurs' were land dwellers.

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Read each description below regarding innervation of the ANS. Then click and drag each into the appropriate category base on whe

Anna35 [415]

The question is incomplete. Here is the complete question.

Read each description below regarding the dual innervation of the ANS. Then click and drag each into the appropriate category base on whether it is an example of antagonic or cooperative innervation.

The sympathetic division stimulates mucus production by salivary glands while the parasympathetic division stimulates enzyme secretion.

The sympathetic division stimulates am increase in heart rate while the parasympathetic division stimulates a decrease in heart rate.

During sex, the parasympathetic division stimulates arousal while the sympathetic division stimulates orgasm.

The parasympathetic division constricts the pupils while the sympathetic division dilates the pupils.

Antagonistic:

Cooperative:

Answer: Antagonistic: The sympathetic division stimulates am increase in heart rate while the parasympathetic division stimulates a decrease in heart rate; The parasympathetic division constricts the pupils while the sympathetic division dilates the pupils.

Cooperative: The sympathetic division stimulates mucus production by salivary glands while the parasympathetic division stimulates enzyme secretion.; During sex, the parasympathetic division stimulates arousal while the sympathetic division stimulates orgasm.

Explanation: The peripheral nervous system is divided in Somatic Nervous System (SNS) and Autonomic Nervous System (ANS). The first is responsible for sensory input and voluntary motion.

Autonomic Nervous System is divided into Sympathetic and Parasympathetic divisions and is controls the fight-or-flight and rest-and-digest situations. Usually, an organ with sympathetic and parasympathetic innervations have antagonic function, such as the heart rate - one system causes the heart rate to increase while the other stimulates the rate to decrease. However there are cases in which the combination of the 2 systems cause an increase of stimulation, producing similar effects.

Analysing each category above, it is deductable that when the sympathetic stimulates mucus production and parasympathetic, enzyme secretion and when the parasympathetic stimulates arousal and sympathetic, orgasm, in both cases, they have cooperative innervation.

On the other hand, when sympathetic stimulates increase in heart rate and parasympathetic, decrease in the rate, as stated before, and one stimulates constriction of the pupils and the other, dilation of the them, those are examples of having antagonic innervation.

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3 years ago

In the female, the development of the "egg" halts during TWO stages, _________ and __________

earnstyle [38]

Answer: The blanks can be correctly filled up with prophase I and metaphase II.

Explanation:

In females, finite number of oocytes are present since birth. The process of oogenesis initiate in embryonic stage only. However, oogonia divide and mature to form primary oocytes. These primary oocytes start meiotic division but arrest in prophase I stage before birth.

After a girl attains puberty, one primary oocyte resumes its division each month during a menstrual cycle. The primary oocyte divides to form secondary oocyte and polar body.

Polar bodies degenerate after completing meiosis II. However, secondary oocyte halts its division again at metaphase II until fertilization takes place. Once fertilization takes place it completes its meiosis II and results into mature ovum and polar body.

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2 years ago

Plant and animal cells both have

aev [14]

Answer:

A nucleus, mitochondria, endoplasmic reticulum, golgi apparatus, and lysosomes.

Explanation:

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lilavasa [31]

I believe the answer is b

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3 years ago

What property of a virus makes it useful for making transgenic organisms?

morpeh [17]

Viruses reproduce by incorporating their DNA into an organism's genome to tap into the host replication mechanism to reproduce themselves. Viruses, therefore, cannot copy outside their host. This property of viruses makes them suitable for the production of transgenic organisms. This is achieved by replacing the DNA piece that causes virulence in the virus with the desired gene that is to be transduced into the host organisms.

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