Presentation on theme: "Chapter 8 Growth and Development Lesson 3 Heredity and the Life Cycle >> Main Menu Next >> >> Chapter 8 Assessment Click for: Teacher’s notes are available."— Presentation transcript:
Chapter 8 Growth and Development Lesson 3 Heredity and the Life Cycle >> Main Menu Next >> >> Chapter 8 Assessment Click for: Teacher’s notes are available in the notes section of this presentation.
chromosomes genes fetus prenatal care Tiny strands of matter that carry the codes for inherited traits The basic units of heredity What the developing unborn baby is known as from the eighth week until birth Special care to ensure that an expecting mother and the baby remain healthy
In this lesson, you will learn to explain how inherited traits are passed along. identify changes to the developing baby. recognize stages in the life-cycle.
Analyzing a Graphic Using this diagram as a guide, describe the stages of development before birth. After 3 months After 6 months After 9 months The Developing Baby
Heredity Heredity is the process by which parents pass certain traits to their children. Hair color and body build are examples of inherited traits.
Heredity Traits are passed along by chromosomes. chromosomes Tiny strands of matter that carry the codes for inherited traits Chromosomes are made up of genes. genes The basic units of heredity
Chromosomes and Fertilization Among each sperm’s 23 chromosomes, one alone determines the gender of the fertilized egg cell. An egg caries only an X chromosome. Sperm carry either an X or Y chromosome. If a sperm carries an X chromosome, a female will result. If a sperm carries a Y chromosome, a male will result.
Development Before Birth The newly fertilized egg travels down the fallopian tube to the uterus. The egg attaches itself to the wall of the uterus. The egg begins to be divided millions of times. The tissues, organs, and body systems are eventually formed.
The Developing Baby TimeSizeFeaturesDevelopment fertilizationmicroscopic arms, legs, fingers, toes, eyes, ears heart is beating; nervous system is forming; cannot survive outside uterus 6 months after fertilization about 14 inches long; weighs about 2 pounds hair, eyebrows, fingernails, toenails can move and kick; sucks thumb; can hear sounds; might survive outside uterus 9 months after fertilization 18–20 inches long; weighs 7–9 pounds smooth skin, fully developed organs eyes open and close; fingers can grasp; body organs and systems can now work on their own; ready for birth
The Developing Baby In the uterus, the fetus receives oxygen and nutrients through a tube called the umbilical cord. fetus What the developing unborn baby is known as from the eighth week until birth
The Developing Baby Throughout pregnancy, an expectant mother needs prenatal care. prenatal care Special care to ensure that the expectant mother and the baby remain healthy Prenatal care includes eating healthy foods, getting enough rest, and seeing the doctor regularly.
The Life Cycle The life cycle is divided into six major stages. InfancyChildhoodAdolescence Early Adulthood Middle Adulthood Late Adulthood Age 1Ages 1–11 Ages 12–18 Ages 19–30 Ages 30–60 Ages 60+
What I Learned Vocabulary Define chromosomes. Lesson 3 Review
What I Learned Recall How many chromosomes are there in most cells of the human body? What is the one exception? Lesson 3 Review
What I Learned Identify Name two developments that may take place during early adulthood. Lesson 3 Review
Thinking Critically Explain What determines whether a baby will be male or female? Lesson 3 Review
Thinking Critically Apply Yvonne hopes to become a lawyer when she reaches adulthood. What skills can she develop now during her teens to help her achieve her career goals? Lesson 3 Review
Chapter 8 Growth and Development Lesson 3 Heredity and the Life Cycle Click for: End of >> Main Menu >> Chapter 8 Assessment