Human Bio

DNA meaning

the chemical that determines the characteristic you inherit

What can DNA code for?

For proteins to be made in cells and also control the characteristics you inherit.

what does DNA + protein = ?

Histones

Where is DNA located?

in the center of the nucleus cells and in the organelle (mitochondria)

Genes

coded sections of DNA that are located on each chromatid of the chromosomes. These can be a characteristic or trait.

Double helix

linked chain of ribose sugar and phosphate molecules

Mitosis

The process of cell division for growth and cell replacement (produces 46 chromosomes)

Meiosis

The process of cell division for reproduction. This process reduces the number of chromosomes in gametes.

Diploid number

The number of chromosomes present in the body cells of a diploid organism

Diploid organism

An organism that has two complete sets of chromosomes.

Number of chromosomes in a DIPLOID cell

46 chromosomes

Number of chromosomes in a HAPLOID cell

23 chromosomes

Process of mitosis

On mother cell divides to produce two daughter cells that are genetically identical to itself.

Male reproductive system

Responsible for sexual function and urination

Male sex cells

sperm that are produced in the testes

Sperm tails

enables them to move through the semen

Seminal vesicles

produces thick sugar rich fluid which provides energy for the sperm.

Testes

produces sperm

Scrotum

Where the testes are located. Keeps the testes at a slightly lower temperature than body temperature.

Vas deferens

tube through which sperm travels from the testes to the penis

Prostate gland

Secretes liquid that is added to sperm cells to form semen. Secreted fluid is alkaline and contains enzymes.

Urethra

The tube inside the penis through which semen leaves the male body

Follicle-stimulating hormone (FSH)

This hormone promotes the growth and development of the seminiferous tubules in the testes, where spermatogenesis occurs

Luteinising Hormone (LH)

Acts on specialised cells called the leydig cells in the testesm stimulating them to produce testerone. LH is particularly active during puberty.

Testosterone

The primary hormone involved in the development and maintenance of male reproductive tissues including testes and prostate.

Spermatogenesis

The process by which sperm cell production occurs.

Female reproductive system

The main function of the reproductive system is to produce eggs to grow, nurture and produce a baby.

Ovaries

Are the female sex organs and produce the female gamete, the ovum or egg.

Ovulation

The process in which an egg is released from an ovary.

Endometrium

The layer of tissue that lines the uterus

Cervix

A muscular, tunnel-like organ that is located in the lower part of your uterus connecting the uterus and the vagina.

Oogenesis

is the creation of an ovum (egg cell)

Zona pellucida

the thick transparent membrane surrounding a mammalian ovum before implantation

Corona radiata

The outmost layer of the ovum which acts as a protective shield to the central oocyte or egg cell.

Polar body

A cell that separates from an oocyte during meiosis and that contains a nucleus produced in the first or second meiotic division and very little cytoplasm.

Endometriosis

A disease in which tissue similar to the lining of the uterus grows outside the uterus.

Oestrogen

is the primarily produced by the developing ovarian follicles.

Progesterone

Primarily produced by the corpus leteum which forms from the remains of the ovarian follicle after ovulation.

Abstinence

protects people against STD’s from vaginal sex

STI’S

-Gonorrhoea

-Chlamydia

-Syphilis

Viral infections

-Genital Herpes

-Human immunodeficiency virus (HIV).

Caesarian Section

(C-section) is the surgical procedure to take out the babies out of the womb.

Embryo

Early stage in development of humans and other animals or plants.

Fertilisation

When the sperm and egg unite in one of the fallopian tubes to form a zygote.

Foetus

The unborn mammalian off-spring that develops from an embryo

Gamete

A haploid cell that fuses with another haploid cell during fertilisation in organisms that reproduce sexually.