Biology table: human development and age processes. Reproduction

16.12.2023

Exercise. Choose one correct answer.

1. Female gametes are called:
A. Follicles
B. Eggs
B. Sperm

2. Human germ cells contain:
A. 46 chromosomes
B. 50 chromosomes
B. 23 chromosomes

3. A female baby develops with the following combination of sex chromosomes:
A. XX
B. XY
V.YY

4. Male gametes are formed:
A. In the prostate gland
B. In the testes
B. In the vas deferens

5. Female gametes are formed:
A. In the fallopian tubes
B. In the uterus
B. In the ovaries

6. The development period of the egg is:
A. 30 days
B. 28 days
B. 25 days

7. Fertilization of the egg occurs:
A. In the fallopian tube
B. In the ovary
B. In the uterus

8. Implantation and development of the embryo occurs:
A. In the fallopian tube
B. In the ovary
B. In the uterus

9. A human zygote contains:
A. 23 chromosomes
B. 46 chromosomes
B. 92 chromosomes

10. Providing the embryo with nutrients and oxygen is carried out with the help of:
A. Placenta
B. Chorion
V. Amnion

11. The gestation period is:
A. 38 weeks
B. 40 weeks
B. 42 weeks

12. With the first cry, the child begins to actively function:
A. Circulatory system
B. Digestive system
B. Respiratory system

13. The child becomes an independent organism:
A. After cutting the umbilical cord
B. After the first breath
B. After the first feeding

15. The development of all primary teeth and the rapid growth of the child occurs during the period:
A. From 3 to 5 years
B. From 1 to 3 years
B. From 5 to 7 years

16. The growth and development of the body is completed:
A. At 10–15 years old
B. At 30–40 years old
B. At 16–21 years old

Exercise. Fill in the missing word.

1. Male and female organisms take part in sexual reproduction, producing sex cells:... and..., the fusion of which forms...
2. A human zygote contains... chromosomes, with the combination of sex chromosomes XX is born..., and XY –
3. Male gonads - ... synthesize germ cells..., the nutrition and development of which is provided by the seminal fluid produced by... the gland.
4. Eggs develop in..., in special vesicles -..., the maturation period is... days.
5. Fertilization occurs in the uterine..., the zygote is implanted into the wall..., where the multicellular...
6. Nutrition, respiration and metabolism of the embryo are provided by a special shell -..., developing from the villi..., the connection between the fetus and the mother’s body is carried out through... the cord.
7. The period of intrauterine development of the embryo is called... and lasts... weeks, during which the human embryo goes through the stages of development of its...
8. As a result of involuntary contractions... the child is born, with the first cry he is dealt with..., and after being cut off... he becomes an independent being.
9. A newborn baby exists thanks to... reflexes, the basis of its nutrition is... milk, and by 6 months they erupt...
10. In the period from 1 to 3 years, the child actively... and grows rapidly, at 12–16 years of age... maturation begins, and by the age of 21 all body systems reach their...

Like any living organism, a person is born, grows, reproduces, ages and dies. A person’s age is calculated from the moment of his birth. On average, human life expectancy in developed countries is 73 years for men and 77 years for women.

Birth. Before giving birth, a woman begins to experience labor pains - involuntary contractions of the uterus, which are helped by periodic contractions of the abdominal muscles. When a baby is born, its lungs expand and with its first cry it begins to breathe on its own.

After the baby is born, the umbilical cord (umbilical cord) is tied in two places and then cut between the bands. The child becomes independent.

Newborn and infant. This small but important period in a person’s life does not last long. A child up to a month is considered a newborn, and up to a year - an infant.

A newborn baby is weak and helpless. Thanks to innate reflexes, he sucks at his mother's breast. Within a month, his body weight increases significantly, and his movements become more complicated. The child can make grasping movements and master the basics of communication. During infancy, the baby grows especially quickly. At about 6 months, baby teeth begin to emerge. A number of organs (eye, inner ear) quickly reach almost adult size.

During this period, the child should receive adequate nutrition. Children best absorb the proteins, fats and carbohydrates of human milk, which is why breastfeeding is so important. In addition, mother's milk contains antibodies and thus protects the baby from many diseases.

Childhood. In the period from 1 year to 3 years, the child has all his milk teeth, he grows quickly and gains weight. The child’s speech and memory develop. He begins to navigate his surroundings and actively explores the world. During this period, play is of great importance for the baby.

Puberty in girls begins at 11-12 years old, in boys a little later - at 12-13 years old. At this time, body proportions change, secondary sexual characteristics appear; In girls, the pelvis expands. hips are rounded, mammary glands are enlarged; In boys, the larynx begins to grow and the voice breaks.

Adolescence. At the age of 12-16, secondary sexual characteristics intensify in adolescents. Girls begin to menstruate: this is a sign that eggs have begun to develop and mature in the ovaries. By the age of 15-16, boys begin to grow hair on their face, body, and armpits, and involuntary discharge of sperm appears—emissions—the first sign of puberty in young men.

Adolescence. This age (16-21 years) coincides with the period of maturation. At this age, the growth and development of the body is basically completed, all organ systems practically reach their maturity.

The structure of the body in adulthood (22-60 years) changes little, but in the elderly (61-74 years) and senile (over 75 years) restructuring characteristic of these ages can be traced: metabolism slows down, and the performance of all organ systems decreases. An active lifestyle and regular physical exercise slow down the aging process.

It is not long before the embryo begins to look like a little person. Indeed, during intrauterine development, a person, like all other mammals, goes through the development of his biological species: at first he looks like a lancelet, then he resembles a small fish, then he develops the features of amphibians and reptiles. All these transformations occur quite quickly, and by the beginning of the 6th week from the moment of fertilization, the embryo already looks like a small man, although its length is only slightly more than 1 cm. The spine of the embryo during this period is still cartilaginous, but there are already hoops on the arms and legs, my heart starts beating.
When a person is born, the volume of his brain is very small. Most of the human brain is formed after birth. A newborn baby hears sounds well, but only after a year does he learn to accurately identify the sources of these sounds.
When a baby is born, he has virtually no motor skills, so he must first learn to hold his head up, then crawl, walk, etc. For most children, the main stages of motor skill development are as follows:
9 months - crawling;
1 year - begins to walk;
1.5 years - can walk well;
2.0 years - runs confidently;
3.0 years - learns to kick a ball;
4.0 years - can jump on one leg;
5.0 years - can walk along a line drawn on the ground;
6.0 years old - good at long and high jump.

As the body develops and the child matures, the proportions of his body change. The head becomes smaller in relation to the length of the body, while the legs and arms become relatively longer.

Test your knowledge

What are labor pains?
When does a child begin to navigate the environment?
What is characteristic of a newborn baby?
What period of a person's life does the infancy period cover?
When does puberty begin in girls?
What are the developmental features of adolescence?
What stage in a person's life coincides with the period of maturity?

Think

Why can't an unborn baby in its mother's body scream?

Human development is divided into the newborn and infant stages, childhood, adolescence and youth, mature, elderly and senile age.

1. What are labor pains?

Labor contractions are involuntary contractions of the walls of the uterus, facilitating the passage of the fetus through the birth canal and expulsion of the fetus during childbirth.

2. Remember how a person’s breathing is regulated. Knowing this, explain the trigger for the first breath of a newborn baby.

In a newborn baby, after ligation of the umbilical cord, gas exchange through the umbilical vessels, which carry oxygen-enriched blood to the fetus, stops. In the blood of a newborn, the amount of oxygen decreases and carbon dioxide increases, which irritates the chemoreceptors located in the area where the carotid artery originates. These receptors send exciting nerve impulses to the respiratory center, which triggers the mechanism of the first breath.

3. What is characteristic of a newborn baby?

The newborn period is considered the first month of a child’s life (according to other sources, the first 10 days of life). During this period, the child is weak and helpless. He has developed unconditioned reflexes (sucking, grasping, proboscis) and has not yet formed conditioned ones. All body systems are imperfect; there are no curves in the spine. The need for sleep is up to 21 hours a day. The child feeds on mother's milk.

4. How is breast milk better than artificial formula?

Mother's milk contains all the substances necessary for the growth and development of the child in a perfectly balanced form. In addition, mother's milk contains antibodies that protect the child from many infectious diseases in the first months of life, when the baby's immune system is still imperfect and cannot provide it on its own.

5.What period of a person’s life is called infancy?

The first year of a child’s life is called infancy. During this period, the child actively grows and develops, children sleep a lot and eat often. They feed on breast milk or artificial formula, hence the name of the period. By the end of the infancy period, all the curves of the spine are formed in the child, the child begins to walk, the first milk teeth appear, the child learns to walk and talk, and the first conditioned reflexes are formed.

6. When does puberty begin in girls; in boys?

Puberty in girls begins at 11-12 years old, in boys a little later - at 12-13 years old. At this time, the proportions of the body change, secondary sexual characteristics appear: in girls, the pelvis expands, the hips are rounded, the mammary glands enlarge, female-type hair growth begins: pubis, armpits; in boys, the larynx begins to grow, the voice breaks, the skeleton begins to grow according to the male type: a wide shoulder girdle and a slowdown in the growth of the pelvic bones. During this period, children grow very quickly and gain weight. So, during this period, growth per year can increase by 20 centimeters! The size of internal organs increases and blood pressure increases.

7. What are the developmental features of adolescence?

At the age of 12–16 years, secondary sexual characteristics intensify in adolescents. In girls, menstruation appears (periodic discharge of blood from the genital tract): this is a sign that eggs have begun to develop and mature in the ovaries, and the amount of hair on the pubis and armpits increases. By the age of 15–16, boys begin to grow hair on their face, body, and armpits, involuntary discharge of sperm appears - wet dreams - the first sign of puberty in young men (they happen from 1 time every 1.5-2 months to 2-3 times a month). month). Through emission, the body is freed from excess seminal fluid and sexual tension.

8 What characterizes the period of maturity in a person’s life; elderly age; period of old age?

The structure of the body in adulthood (22–60 years, according to other sources from 21 to 60 years in men and up to 55 years in women) changes little; this period can also be characterized as a period of relative constancy and stability of body functions at the highest level of its development in its first half (up to 35 years) and a period of slow decline after 35 years, the period of maturity accounts for the greatest increase in human labor and social activity. In the elderly (61–74 years) and senile (over 75 years) changes in the body characteristic of these ages can be observed: metabolism slows down, the performance of all organ systems decreases, mental activity slows down, memory is impaired, the skin loses elasticity, age spots of varying degrees appear severity, signs of keratinization, wrinkles, first on the earlobes, bridge of the nose, chin and upper lip, later on the skin of the cheeks, forehead, neck, becoming deeper and more noticeable every year. In an elderly person, with rare exceptions, the figure, posture and gait noticeably change, which is associated with age-related changes in the joints, muscles and skeleton. The gait becomes heavy, slow, and in old age can become “shuffling.” All these processes are more pronounced in obese people.

9. There are known cases where children from infancy were isolated from human society and grew up among animals. When they got to people, these “Mowgli” children, aged 5 years or more, never learned to speak and read well. Explain why.

The lack of human communication in a child leads to abnormalities in the formation of brain cells and a slowdown in communication between its various areas, which are formed between the ages of 3 and 6 years. Social isolation in the first years of a person's life leads to severe emotional instability and mental retardation.

10. Why can’t an unborn baby in its mother’s body scream?

Sounds, including screams, are formed when air passes through the vocal folds, since the fetus does not breathe, it therefore cannot produce sounds.

187 Write down the definitions

Homologous chromosomes are

Answer:

Homologous chromosomes are chromosomes that contain the same linear sequence of genes and form pairs during meiosis.

A diploid chromosome set is

Answer:

A diploid chromosome set is a set of chromosomes contained in each cell of the body.

188 Look at the drawing. Write the names of the parts of the male reproductive system indicated by numbers

Answer:

Penis
Urethra
Foreskin
Testicle
Scrotum
Epididymis
Prostate
Vas deferens

189 List the organs that make up the female reproductive system

Answer:

Ovaries, fallopian tubes, uterus

190 Complete the offer

Male reproductive cells - Female reproductive cells -

Answer:

Male reproductive cells - sperm - are formed in the testicles. Female reproductive cells - eggs are formed in the ovaries.

191 Write down the definitions

Fertilization, zygote, placenta

Answer:

Fertilization- This is the fusion of an egg and a sperm.

Zygote is a germ cell that is formed as a result of fertilization

Placenta- over time, as the embryo grows, the placenta is formed from the surrounding membranes and vessels of the uterine mucosa

192 What are the structure and functions of the placenta?

Answer:

The placenta has the shape of a disk about 20 cm and a thickness of about 5 cm. In it, the blood vessels of the mother and the embryo come into contact without merging with each other. The placenta supplies the embryo with nutrients and oxygen. It also protects the embryo from foreign substances.

193 Explain the advantages of sexual reproduction over asexual reproduction

Answer:

With sexual interbreeding, genes are crossed, and they inherit the characteristics of both parents; with asexual, the offspring receive the genome of the parent and actually do not differ from it.

194 Describe the main stages of human development

Answer:

Birth- After birth, his umbilical cord is tied in two places and then cut between the bands. The child becomes independent.

Newborn- the child is weak and helpless. Thanks to innate reflexes, he sucks at his mother's breast. Within a month, its mass increases significantly, and movements become more difficult.

Infant- At this age, the baby grows especially quickly. At about 6 months, baby teeth begin to emerge. A number of organs (eyes, etc.) quickly reach almost adult size.

Childhood- In the period from 1 year to 3 years, all baby teeth erupt in a child. The child’s speech and memory develop. He begins to navigate the world around him.

Adolescence - At the age of 12-16, secondary sexual characteristics intensify in adolescents. By the age of 15-16, boys begin to grow facial hair, etc.

Adolescence- (16 - 21 years) coincides with the period of maturation. At this age, the growth and development of the body is basically completed, all organ systems practically reach their maturity.

Mature age- The body structure at this age (22 -60) will change little.

Elderly age- Old age (61 - 74 years) shows a restructuring characteristic of these organs: metabolism slows down, and performance decreases.

Senile age- (75 - 90 years)

Exercise. Choose one correct answer.

1. Female gametes are called:

A. Follicles

B. Eggs

B. Sperm

2. Human germ cells contain:

A. 46 chromosomes

B. 50 chromosomes

B. 23 chromosomes

3. A female baby develops with the following combination of sex chromosomes:

4. Male gametes are formed:

A. In the prostate gland

B. In the testes

B. In the vas deferens

5. Female gametes are formed:

A. In the fallopian tubes

B. In the uterus

B. In the ovaries

6. The development period of the egg is:

7. Fertilization of the egg occurs:

A. In the fallopian tube

B. In the ovary

B. In the uterus

8. Implantation and development of the embryo occurs:

A. In the fallopian tube

B. In the ovary

B. In the uterus

9. A human zygote contains:

A. 23 chromosomes

B. 46 chromosomes

B. 92 chromosomes

10. Providing the embryo with nutrients and oxygen is carried out with the help of:

A. Placenta

B. Chorion

V. Amnion

11. The gestation period is:

A. 38 weeks

B. 40 weeks

B. 42 weeks

12. With the first cry, the child begins to actively function:

A. Circulatory system

B. Digestive system

B. Respiratory system

13. The child becomes an independent organism:

A. After cutting the umbilical cord

B. After the first breath

B. After the first feeding

A. Up to 1 month

B. Up to 3 months

B. Up to 12 months

15. The development of all primary teeth and the rapid growth of the child occurs during the period:

A. From 3 to 5 years

B. From 1 to 3 years

B. From 5 to 7 years

16. The growth and development of the body is completed:

A. At 10–15 years old

B. At 30–40 years old

B. At 16–21 years old

Option 2

Exercise. Fill in the missing word.

1. Male and female organisms take part in sexual reproduction, producing sex cells:... and..., the fusion of which forms...

2. A human zygote contains... chromosomes; when sex chromosomes are combined, XX is born..., and XY is...

3. Male gonads - ... synthesize germ cells..., the nutrition and development of which is provided by the seminal fluid produced by... the gland.

4. Eggs develop in..., in special vesicles -..., the maturation period is... days.

5. Fertilization occurs in the uterine..., the zygote is implanted into the wall..., where the multicellular...

6. Nutrition, respiration and metabolism of the embryo are provided by a special membrane -..., developing from the villi..., the connection between the fetus and the mother’s body is carried out through... the cord.

7. The period of intrauterine development of the embryo is called... and lasts... weeks, during which the human embryo goes through the stages of development of its...

8. As a result of involuntary contractions... the child is born, with the first cry he is dealt with..., and after being cut off... he becomes an independent being.

9. A newborn baby exists thanks to... reflexes, the basis of its nutrition is... milk, and by 6 months they erupt...

10. In the period from 1 to 3 years, the child actively... and grows rapidly, at 12–16 years of age... maturation begins, and by the age of 21 all body systems reach their...