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.
You forgot to put the options, but i believe it is magma.
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I have absolutely no clue
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Each species has a specific identifying number of chromosomes. For example, a cat, <em>Felis catus</em>, has 38 chromosomes, while corn, <em>Zea mays</em>, has 20 chromosomes each chromosome carries specific genes that are unique to that chromosome.
Explanation:
Chromosomes vary in shape and number among living beings. For example, the bacterial chromosome is a unique circular molecule, while human beings have 46 lineal chromosomes arranged in pairs (23 pairs). The total number of chromosomes is specific to each species, and it is denoted as the "chromosomic dotation" of the species.
Genes are the hereditable units that transmit the information needed to specify traits, from parents to offspring, generation to generation. Genes are arranged in sequence in the chromosomes. A chromosome might contain hundreds of thousands of genes.
Genes vary in size and shape. They are composed of pairs of bases, and these sequences also vary in number, producing genes of different lengths. In general, genes code for proteins. Proteins create the organism tissues and perform or carry out specific functions in the organisms, controlling almost all processes and chemical reactions.
Each chromosome carries <u>specific</u> genes that code for <u>specific </u>proteins that have <u>specific</u> functions in the organisms. Each chromosome carries information to synthesize different proteins needed to accomplish a certain function. But <u>not all chromosomes carry the same gene sequences</u>. Only homologous chromosomes carry information for the same trait, but even this information is not necessarily the same. They might have the same gene but different alleles.
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No. If a women cant have a child, its just called female infertility refers to infertility in women. But they are still alive
