Tema Regnul Animale, Încrengătura Celenterate Anul I

Animalele la care embrionul este format din trei straturi de celule se numesc "triblasterice". This is the correct answer because "triblasterice" refers to animals that have three germ layers during embryonic development. These germ layers, known as the ectoderm, mesoderm, and endoderm, give rise to different tissues and organs in the developing animal. This is a fundamental characteristic of many animal species and is an important aspect of their development and body plan.

The statement is true because cnidarians, which are a type of cnidarian, exhibit radial symmetry. This means that their body parts are arranged around a central axis, allowing for multiple planes of symmetry. This is in contrast to animals with bilateral symmetry, which have only one plane of symmetry. Therefore, the statement accurately describes the characteristic of cnidarians and their ability to have multiple axes of symmetry.

Animalele homeoterme sunt acele animale care își mențin temperatura corpului constantă, indiferent de temperatura mediului înconjurător. Acest lucru se realizează prin mecanisme de termoreglare interne, cum ar fi producerea și conservarea căldurii sau răcirea corpului, pentru a menține temperatura constantă într-un interval optim pentru funcționarea organismului. Prin urmare, afirmația că animalele homeoterme au temperatura corpului constantă indiferent de temperatura mediului extern este adevărată.

Animalele poikiloterme își obțin sursa de energie din mediul extern, deoarece nu pot regla temperatura corpului lor intern. Aceste animale nu produc suficientă energie metabolică pentru a menține o temperatură constantă, așa că își ajustează temperatura corpului în funcție de temperatura mediului înconjurător. Astfel, ele își obțin energia termică din mediul extern, deoarece temperatura lor este apropiată de cea a mediului în care trăiesc.

The correct answer is "difuz." The explanation for this is that in Celenterates, which include organisms like jellyfish and sea anemones, the nervous system is diffuse. This means that the nerve cells are spread throughout the body and not organized into a centralized system like in more complex organisms. The diffuse nervous system allows for basic sensory and motor functions in these simple organisms, but it is not as specialized or complex as the nervous systems found in higher animals.

Glandular cells secrete enzymes that play a role in digestion. This is true because glandular cells, such as those found in the stomach and pancreas, produce and release digestive enzymes that help break down food molecules into smaller, more easily absorbable components. These enzymes are essential for the process of digestion and nutrient absorption in the body.

The statement is false because in amniotes, the development of the embryo takes place in a terrestrial environment rather than an aquatic one. Amniotes are a group of vertebrates that includes reptiles, birds, and mammals. They have evolved an amniotic egg or a placenta, which allows the embryo to develop outside of water. This adaptation enables them to live and reproduce in various terrestrial habitats. Therefore, the correct answer is false.

The movement and protection in Celenterates are provided by muscular cells.

The given statement is false. Sexual reproduction in cnidarians, such as jellyfish and sea anemones, does not occur through budding. Instead, cnidarians reproduce sexually by releasing eggs and sperm into the water, where fertilization takes place externally. The fertilized eggs then develop into larvae, which eventually settle and grow into new individuals. Budding is a form of asexual reproduction commonly found in cnidarians, but it does not involve sexual reproduction.

The correct answer is "buco-anal." In Celenterates, the orifice surrounded by a cluster of tentacles is called the buco-anal orifice.

The term "mezogleea" refers to the gelatinous layer found between the ectoderm and endoderm in cnidarians. This layer acts as a support structure for the organism and helps maintain its shape. It also contains cells that are involved in various physiological processes, such as nutrient transport and defense against predators. The mezogleea is an important component of the body plan of cnidarians and plays a crucial role in their biology.

The correct answer is "radiala" because the body plan of cnidarians, such as jellyfish and sea anemones, is characterized by radial symmetry. This means that their body parts are arranged around a central axis, like the spokes of a wheel. They can be divided into equal halves in multiple planes, and any slice passing through the central axis will produce mirror image halves. This type of symmetry allows them to interact with their environment from all directions and enables efficient movement and feeding strategies.

Celenteratele sunt animale acvatice, iar respirația lor se realizează prin suprafata corpului, unde oxigenul dizolvat în apă este absorbit și dioxidul de carbon este eliminat. Această adaptare permite schimbul de gaze cu mediul înconjurător și asigură necesarul de oxigen pentru organismele celenterate.

The given statement states that intracellular digestion occurs in the gastric cavity under the action of digestive juices secreted by glandular cells. However, this statement is incorrect. Intracellular digestion actually occurs within the cells themselves, where enzymes break down food particles into smaller molecules. The correct answer is false because the statement is not accurate.

Meduza are tentacule, umbrela, oceli și alternarea generațiilor. Aceste caracteristici sunt specifice meduzelor și le diferențiază de alte organisme. Tentaculele sunt utilizate pentru hrănire și apărare, umbrela este structura în formă de clopot care le permite să se deplaseze în apă, ocelii sunt ochii simpli ai meduzelor și le ajută să detecteze lumină și umbre, iar alternarea generațiilor se referă la ciclul de viață al meduzelor, care include stadii de meduză și de polip.

The given correct answer is "Înmulțirea asexuată a polipului". This is because the question asks which stage of the life cycle of a jellyfish corresponds to the number 4. Looking at the options, "Înmulțirea asexuată a polipului" is the fourth stage mentioned in the list. The other stages mentioned before it are "Meduza tânără", "Zigotul", and "Planula". Therefore, the correct answer is the fourth stage, which is "Înmulțirea asexuată a polipului".

Celenterates are characterized by the presence of stinging cells called cnidocytes, which have the dual function of protection and attacking prey. These cells contain specialized structures called nematocysts, which can release venomous threads to immobilize or kill their prey. Therefore, the correct answer is "celulele urzicatoare" (stinging cells).