Download presentation
Presentation is loading. Please wait.
Published byGavin Fitzgerald Modified over 8 years ago
1
Sexual Reproduction Notes Take out a sheet of paper and prepare to take notes.
2
Reproduction ASEXUALSEXUAL Brainpop Requires only one organisms offspring that are identical to parent. In plants, it’s called vegetative reproduction. Requires two parents, a male and a female offspring are genetically different than the parents Requires the use of gametes, also known as sex cells
3
Plants that Produce Seeds TypesTypes of Seeds Gymnosperms Angiosperms Makes “naked” seeds. Seeds are not enclosed in a case (ex: pine trees) Needle-like or scale-like leaves. Deep Growing roots. Seed develops after fertilization. Produce flowers. Enclosed seeds Seed develops after fertilization.
4
Anatomy of a flower Draw and label the structure of the flower on page 393.
5
What is pollination? What is the female part of the flower called? What is the male part of the flower called? What happens when a pollen grain lands on the pistil of a flower? What does each fertilized ovule become? THE TRANSFER OF POLLEN FROM THE ANTHER TO THE PISTIL. PISTIL STAMEN IT TRAVELS THROUGH THE STYLE TO THE OVARY TO FERTILIZE THE EGG A SEED
6
Fertilization PLANTSANIMALS (INCLUDING HUMANS) What happens during fertilization? When does fertilization take place? Pollen grains Bee carrying pollen Plant ovary w/egg cells Human egg cell takes place when a sperm cell meets the egg cell; genetic information is exchanged. pollen is carried by wind, water, and animals to the stigma, the female part of the plant (stigma— part of the pistil) sperm joins egg after sexual reproduction
7
Reproduction PLANTSANIMALS (INCLUDING HUMANS) What if fertilization is successful? What if fertilization is unsuccessful? Gametes sexual reproduction requires male (sperm) and female (egg) gametes The zygote in plants forms an embryo and then a seed. The zygote in animals forms an embryo then a fetus. No seed or fruit is produced. the egg is evacuated. Animals go through a process known as menstruation.
8
Baby Growth & Development What structure carries nutrients between the mother’s placenta and the fetus? What is the purpose of the placenta? It is truly an amazing transformation. From a tiny fertilized egg (no bigger than the period at the end of a newspaper sentence) to a 7- 8 lb complete human being in a mere 280 days from the last menstrual period (approx. 265 days from conception). There is no comparable miracle in all of nature. Below is a month by month guide to fetal growth and development. Month 1 (0-6 weeks) Following conception, the cells divide rapidly and begin to form primitive organs (spinal cord, heart, etc). The embryo is 1/4 inch in length by 4 weeks (10,000 times larger than at conception). The heart begins to beat. The placenta begins to grow and makes a hormone (HcG) that is used to diagnose pregnancy. Month 2 (6-10 weeks) The embryo is now 1 1/8 inch by 8 weeks. The heart is beating and functioning. The eyes, nose, and teeth buds are formed and the embryo starts to move it’s arms and legs. Organs (spinal cord, stomach, liver, kidneys, etc) are quickly developing in structure. An ultrasound performed at this time can see the embryo. Umbilical cord To exchange substances between the fetus and the mother.
9
Baby Growth & Development Month 3 (10-14 weeks) The fetus is 2 1/2 to 3 inches long and weighs 1/2 to 1 oz. The hands, arms, legs, and toes are fully developed. Most organs have completed structural development but not all are functioning yet. Fetal movement can be seen on ultrasound (although not detected by the mother). Month 4 (14-18 weeks) The fetus is now 6-7 inches long and weighs 7 oz. The fingers and toes become more defined. The gender of the fetus can be clearly seen. The fetus exhibits reflex activity such as swallowing and the kidneys begin to make urine. The skin is thin and transparent. Month 5 (19- 23 weeks) The fetus has grown to 8-10 inches and now weighs 3/4 to 1 lb. Fetal hair begins to grow (including eyebrows and eyelashes) and fetal movement (“twitches”) may be felt by the mother. The organs continue to mature functionally but are still immature. Babies born at this time have a poor chance of survival. Month 6 (24-28 weeks) The fetus is now 12- 14 inches long and weighs 1 1/2 to 2 lbs. If born during this period, he/she has increasing chance for survival. Fetal hiccupping begins. Eye movement (opening and closing) begins. Babies can be seen on ultrasound sucking their thumbs.
10
Baby Growth & Development Month 7 (28-32 weeks) The fetus is now 14-17 inches long and weighs 2-3 1/2 lbs. The skin becomes less transparent as fat deposits develop under the skin and in other areas. Brain tissue is forming rapidly. He/She may respond to loud noises. Organs are almost fully mature except for the lungs. Cycles of sleep and wakefulness become more noticeable. Month 8 (32-36 weeks) The fetus has grown to 17-19 inches long and now weighs 3 1/2-6 lbs. This is the most rapid period of body growth. Hair follicles develop. If born, baby has excellent chance of survival. He/She begins to move down into the pelvis in preparation for birth. Month 9 (36-40 weeks) The fetus is now fully developed. He/She is 19-22 inches long and weighs 6-8 lbs. The lungs become mature and all organs are completely functioning. The head is deep into the pelvis, and false labor is common. The signal that begins labor is still not fully understood. It is clear that the fetus “signals” the uterus through production of hormones and proteins. Under the influence of these products, contractions begin and the long and miraculous journey from those few cells to your healthy newborn baby is completed. Editorial provided by Dr. Charles Ingardia, Director, Fetal-Maternal Medicine Obstetrics and Gynecology at Hartford Hospital.
11
The End
12
Gametes: sexual reproduction requires male and female gametes The male gametes are called sperm. - sperm carry the genetic traits from the father/male - in animals (including humans), sperm is produced in the testes - in plants, sperm is produced in the anther in and is encased in grains of pollen - sperm is ejected from the male (in humans, during sexual intercourse) to the egg of the female What are sperm?
13
The female gametes are called eggs. - eggs carry the genetic traits from the mother/female to the offspring - in animals (including humans), eggs are produced in the ovaries - in plants, ovaries are sectioned off into chambers called ovules - the ovary in plants develop into fruit - eggs are stored in the female organs until they are fertilized by the male’s sperm What are eggs? How do eggs differ in animals and plants?
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.