Human performance

Classified in Biology

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HUMAN REPRODUCTION • It´s a sexual reproduction: two gametes (reproductive cells) from different sexes join together to produce a zygote which develops into a new individual. • Gametes are formed in the reproductive organs called gonads of the reproductive system. – Male gonads:Testes produce spermatozoa. – Female gonads : Ovaries produce ova. • The sex is the biological condition determined by the gonads. • The sexuality includes the sex, emotions, feelings, sex-related experiences not always related with reproduction.• Adolescence is a stage from 11 to 18 years old approximately. • It starts with puberty which marks the beginning of reproductive capacity. CHANGES DURING ADOLESCENCE • As a result of the secretion of sex hormones into the bloodstream. • Body growth. • Development of primary sexual characteristics that allow: – Girls: First menstruation. – Boys: First ejaculation. • Development of secondary sexual characteristics: – Girls: Growth of: sex organs, breasts and hips. Waist become thinner. Growth of hair in pubic and underarms areas. – Boys: Growth of: sex organs, shoulders, muscle mass. Drop in voice. Growth of hair in pubic , underarms areas, chest and face. • Psychological changes: Personality, independence, conflicts, sexual attraction, emotional crises, firm friendship. THE MALE REPRODUCTIVE SYSTEM :FUNCTIONS • It manufactures spermatozoa (male gametes). • It deposits spermatozoa in the female reproductive system. • It produces male sex hormones (testosterone). PARTS • Testes: Glands inside the scrotum. Made up of seminiferous tubules. They produce testosterone and spermatozoa. • Epididymis:It stores the spermatozoa while they mature. • Vasa deferentia: Connect the epididymis to the urethra. • Penis: Erectile tissue that grows when recives blood, becoming erect. The end (gland) is protected by the foreskin. ACCESORY GLANDS • They produce secretions that with spermatozoa make up the semen • Seminal vesicles. • Prostate. • Cowper´s glands. SPERMATOZOA
• Are small mobile cells that carry the hereditary information from the father. • PARTS: – Head: Cell nucleus with genetic material. – Mid-piece: With a lot of mitochondria to produce energy for movement. – Tail or flagellum: To move.

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