Solution:

Term for Chemical Secretions of Endocrine Glands Responsible for Changes in the Body

The chemical secretions of endocrine glands that are responsible for changes taking place in the body are called hormones.

Solution:

Definition of Adolescence

Adolescence is the period of life between childhood and adulthood. It is a time of significant physical, emotional, and psychological changes. During this phase, an individual undergoes puberty, which leads to sexual maturity. Adolescents develop new interests, form a sense of identity, and experience increased independence. It typically occurs between the ages of 10 and 19 years.

Solution:

What is Menstruation? Explain.

Menstruation is a natural biological process in females, where the lining of the uterus (womb) sheds if pregnancy does not occur. It is a part of the menstrual cycle, which typically lasts about 28 days, although it can vary from person to person. The process is also known as a period.

During the menstrual cycle, the body prepares for a possible pregnancy. The uterus builds up a thickened lining to support a fertilized egg. If fertilization does not happen, the body sheds this lining through the vagina, resulting in menstrual bleeding. This bleeding usually lasts for 3 to 7 days.

Menstruation is controlled by hormones like estrogen and progesterone. These hormones help regulate the release of eggs from the ovaries (ovulation) and the preparation of the uterus lining. Menstrual cycles typically begin during puberty and continue until menopause, which usually occurs around the age of 50.

The process of menstruation is a normal part of female reproductive health and occurs monthly, unless interrupted by factors such as pregnancy, illness, or hormonal imbalances.

Solution:

Changes in the Body that Take Place at Puberty

At puberty, various physical and hormonal changes occur in both males and females. These changes mark the transition from childhood to adulthood. The main changes that take place at puberty are:

• Growth Spurts: The body experiences rapid growth, and height increases significantly.
• Development of Secondary Sexual Characteristics: These include changes like the growth of body hair (underarms, pubic area), broadening of shoulders in males, and development of breasts in females.
• Changes in Voice: In males, the voice becomes deeper as the vocal cords grow longer and thicker. In females, the voice may become slightly deeper but not as drastically as in males.
• Menstruation (in females): The onset of menstruation (also called periods) marks the start of a female's ability to reproduce.
• Increased Sweating and Oil Production: The skin starts producing more oil, which can lead to acne, and there is an increase in sweat production.
• Development of Reproductive Organs: In females, the ovaries mature, and in males, the testes mature, leading to the production of eggs and sperm, respectively.
• Hormonal Changes: The body produces higher levels of sex hormones like estrogen in females and testosterone in males, which are responsible for the physical changes during puberty.
• Changes in the Brain: The brain undergoes development, affecting emotions, mood, and behavior.

Solution:

Endocrine Glands and Their Secreted Hormones

Solution:

What are Sex Hormones? Why are they Named So? State Their Function.

Sex hormones are chemical substances that regulate the development of sexual characteristics and the reproductive processes in the body. These hormones are produced mainly by the gonads (testes in males and ovaries in females), and their production is controlled by signals from the pituitary gland and hypothalamus.

They are named "sex hormones" because they play a key role in the development of sexual characteristics and reproductive function, which distinguish males from females. The primary sex hormones include:

• Testosterone: The main male sex hormone, responsible for the development of male secondary sexual characteristics like deep voice, facial hair, and muscle growth.
• Estrogen: The main female sex hormone, responsible for the development of female secondary sexual characteristics like breast development and the regulation of the menstrual cycle.
• Progesterone: A hormone in females that helps maintain pregnancy and regulates the menstrual cycle.

The function of sex hormones includes:

• Regulating the growth and development of sexual characteristics during puberty.
• Controlling the menstrual cycle in females.
• Supporting reproductive processes such as sperm production in males and egg maturation in females.
• Maintaining sexual behavior and fertility.

Solution:

(a) Adolescents should be careful about what they eat, because

(b) Reproductive age in women starts when their

(c) The right meal for adolescents consists of

Solution:

Adam's Apple

The Adam's apple is a prominent feature of the human neck, which is formed by the thyroid cartilage surrounding the larynx (voice box). It is more noticeable in males than in females due to the difference in the size of the larynx. The size of the Adam's apple increases during puberty in males due to the growth of the larynx, which deepens the voice. This growth is a secondary sexual characteristic, and it is influenced by the hormone testosterone.

Secondary Sexual Characters

Secondary sexual characters are traits that distinguish males from females but are not directly involved in reproduction. These characters develop during puberty and are influenced by sex hormones. In males, secondary sexual characteristics include the growth of facial and body hair, deepening of the voice (due to the Adam's apple), and increased muscle mass. In females, secondary sexual characteristics include the development of breasts, widening of the hips, and the beginning of menstruation. These characteristics help in distinguishing the sexes but are not directly involved in reproduction.

Sex Determination in the Unborn Baby

Sex determination in an unborn baby is controlled by the chromosomes inherited from both parents. Humans have 23 pairs of chromosomes, and one pair determines the sex of the baby. Females have two X chromosomes (XX), while males have one X and one Y chromosome (XY). During fertilization, the sperm carrying either an X or Y chromosome combines with the X chromosome of the egg. If the sperm carries an X chromosome, the baby will be female (XX). If the sperm carries a Y chromosome, the baby will be male (XY). This process determines the biological sex of the baby.

Solution:

Word game: Use the clues to write down the words.

Across

Down

Solution:

Both males and girls experience an abrupt increase in height throughout puberty. As we can see from the graph, girls are shorter than boys between the ages of 4 and 8. However, females' height suddenly increases and surpasses that of boys as soon as they enter the adolescent era, which lasts from 12 to 13 years. For boys, the rate of height gain rises in later years. Growth in both sexes often stabilizes after the age of 20.