The Gymnosperms and Angiosperms are groups of plants with seed, which means that they don’ t necessary acquire water for fertilization. These groups have made adaptations for sexual reproduction on dry land.

1) Gymnosperms (plants with the seeds are not enclosed in an ovary) have developed over the course of its evolution, structures that solved the main limitations present in the Pteridophytes in relation to sexual reproduction, in the terrestrial environment. The main changes that happened as an evolutionary adaptation to dry land are those on the seeds and pollen. The advantages of the seeds are: the storage tissue which sustains growth and a protective coat of the seeds. Seed is enveloped with the layers of hardened tissue which prevents desiccation. This is what frees reproduction from the need for a constant supply of water. <span>The sperm (male gamete) of gymnosperms</span> is enclosed in a pollen grain. Thi structure is protected from desiccation and can reach the female organs without dependence on water. Gymnosperms also developed structures called cupules to enclose and protect the ovule (the female gametophyte) which will develop into a seed upon fertilization.

2) Angiosperms are a group of plants which protect their seeds within an ovary called a fruit. Angiosperms have special evolutionary adaptations. For example, they produce their gametes in separate organs, usually in a flower, so the fertilization and embryo development takes place inside an anatomical structure. That provides a stable system of sexual reproduction largely sheltered from environmental fluctuations like water need.

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2 years ago

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Answer both A and B. Thank you.

Margarita [4]

Explanation:

a.catalase

b.It plays important roles in host defense and oxidative biosynthetic reactions. In addition there is growing evidence that at low levels, H2O2 also functions as a signaling agent, particularly in higher organisms.

<h2>hope it helps.</h2><h2>stay safe healthy and happy..</h2>

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2 years ago

¿Cuáles son los alimentos que contribuyen una fuente rica en vitaminas y minerales ? A) Cereales y tubérculos B) Leguminosas y f

tino4ka555 [31]

Answer:

todas las opciones son correctas

Explanation:

Las vitaminas y minerales son micronutrientes esenciales que deben ser consumidos a través de la dieta parra llevar a cabo funciones metabólicas y fisiológicas diarias. Es importante destacar que existe una excepción a esta regla: la vitamina D puede ser sintetizada por células de la piel mediante una adecuada exposición a la luz del sol. Todos los alimentos destacados en las opciones mencionadas son ricos en determinados grupos de vitaminas y minerales:

- Cereales: ricos en vitaminas del grupo B y minerales, principalmente fosforo y potasio

- Tubérculos (por ej., la papa y la batata): ricos en vitaminas A y C, y minerales, principalmente potasio, fósforo y magnesio

- Leguminosas: ricos en vitaminas del grupo B y vitamina C, y minerales tales como potasio, hierro y magnesio

- Frutas y Verduras: ricos en vitaminas de todos los grupos y minerales esenciales tales como potasio, hierro, magnesio, fósforo, calcio, zinc, etc.

- Carnes: ricos en vitaminas del grupo B y minerales, principalmente hierro, fósforo, calcio, potasio, magnesio selenio y zinc

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2 years ago