Category: Biology

CSEC Study Guide 1

In this study guide series, you will be given a PDF file which will contain concise revisions on different topics in different subjects. You can choose whether or not to download the particular study guide based on the summary provided in the body of the post here. All the subjects below are in one file…...

Introduction to Reproduction in Animals

 Introduction to Reproduction in Animals In order for an animal to prevent its extinction, it needs to reproduce. Just as in the case of plants where there has to be male and female gametes, so it is in the case of animals. In fact, sexual reproduction in plants and animals are very similar. For the…...

Male Reproductive System

Male Reproductive System The diagram below shows the male reproductive system. Vas deferens (sperm duct) – transports sperm to the urethra. Bladder – stores urine. Urethra – carries urine and sperm to the penis where they are released. Penis – deposits sperm into the vagina and also gets rid of urine. Testis – one of…...

Female Reproductive System

Female Reproductive System In humans, as is the case with mammals, the females carry the developing offspring inside. Fallopian tubes (oviducts) – channels the egg down to the uterus. Fertilization occurs here. Ovary – produces and releases a mature egg each month. Uterus – protects and nourishes the developing baby. The endometrium lines the uterus.…...

The Menstrual Cycle and Pregnancy

The Menstrual Cycle and Pregnancy This cycle occurs in females only and happens on a monthly basis. A typical cycle is 28 days long and begins with menstruation (period). Changes in hormone levels make this cycle possible. The two hormones involved are oestrogen and progesterone. NOTE: the menstrual cycle is not the same thing as…...

Birth Control

Birth Control The term birth control (contraception) is quite self-explanatory. It involves means by which individuals try to regulate the occurrence of pregnancy. There are natural and artificial means of contraception. Natural methods of contraception include: -Rhythm method – sexual intercourse is limited to the ‘safe period’ of the menstrual cycle. -Withdrawal method – no…...

Introduction to Reproduction in Plants

Introduction to Reproduction in Plants Reproduction may be described as the process by which an offspring (new organism) is produced. Plants may reproduce asexually and sexually.  Some plants may utilize both means of reproduction depending on the circumstances. In asexual reproduction, there are usually no gametes involved and one plant will produce an offspring on…...

Natural forms of vegetative propagation

Natural forms of vegetative propagation Vegetative propagation involves artificial and natural means by which plants reproduce. Natural means of vegetative propagation includes: Runners/stolons: some plants produce long side shoots that develop roots, eventually forming a new plant. Example Strawberry, Spider plant. Leaves: some plants, such as the Leaf of Life, have young plants on their…...

Germination

Germination Germination is the process by which a seed develops into a seedling. Seeds germinate when they encounter suitable conditions. Some seeds may be dormant for very long periods before they start to develop into new plants. The conditions necessary for germination are: *Water- which activates the enzymes in the seed. *Oxygen- which is needed…...