9.5 Human Biology PDF

9.5: Human Biology Key topics: Definitions The Kidney Male & Female reproductive organs Fertilisation Factors affecting pregnancy Diploids & Haploids (The sex of a baby) Definitions: Renal → relating to the kidneys Excretion → the process of eliminating or expelling w...

9.5: Human Biology Key topics: Definitions The Kidney Male & Female reproductive organs Fertilisation Factors affecting pregnancy Diploids & Haploids (The sex of a baby) Definitions: Renal → relating to the kidneys Excretion → the process of eliminating or expelling waste Filtration → a biological operation that results in the separation of solid matter from a liquid Urea → a colorless substance formed by the breakdown of protein in the liver Urine → liquid waste produced by the kidneys, contains urea and uric acid DNA → the genetic information inside the body’s cells that helps make people who they are Chromosomes → a structure found inside the nucleus of most living cells, carrying genetic information in the form of genes. Each cell normally contains 23 pairs of chromosomes. Characteristics → the distinctive features or traits of an organism Trait → a characteristic of an organism passed down through its genes. Traits can be physical, like eye color or hair color. Fusion → a process where two or more cells combine to form a single cell or structure. Important for organ development, immune response, and sexual reproduction. Fertilization → the process where a male sperm fuses with a female egg to form a zygote (a fertilized egg) , marking the development of a new organism Egg → a reproductive cell produced by the female ovaries. Contains the genetic material and nutrients needed to develop an embryo. Sperm → the male reproductive cell, formed in the testicle. Unites with an egg to form an embryo Gamete → a reproductive cell, such as a sperm or egg (sex cells) Inheritance → the process of passing genetic traits from parents to their offspring, such as hair color or eye color. XX → the notation for a female’s sex chromosomes. (a pair of identical X chromosomes) XY → the combination of sex chromosomes that determine as male biological sex Fetus / Foetus → an unborn offspring that develops and grows inside the uterus (womb) of humans. Offspring → the young produced by a living organism. (a child) Development → the process by which a fertilized egg gradually transforms into a complex, fully formed organism. The Kidney: MRS GREN: Movement Respiration Sensitivity Growth Reproduction Excretion Nutrition Structure of the Kidney: The main job of the kidneys is to remove waste from the blood and return the cleaned blood back into the body That is why the kidneys need to have a rich blood supply  The kidneys also remove acid that is produced by the cells of the human body and maintain healthy balance of water, salts, and minerals. Kidneys produce urine, which contains water (about 95%), salts, urea, uric acid, and other waste products (ammonia, creatinine) Kidney failure: Kidney failure can be caused by diabetes, as high blood sugar levels can damage the small blood vessels in the kidneys, and high blood pressure, as uncontrolled high blood pressures can put excessive strain on the kidneys. A person with kidney failure will die if not treated as it can cause a buildup of dangerous levels of waste and fluid in the body. There are solutions to kidney failure: Kidney dialysis Peritoneal dialysis Kidney transplant Male & Female reproductive organs: The female organs: The male organs: Fertilisation: Egg cells: Key words; yolk, nucleus, jelly coat, cortical granules Yolk produces energy for division Nucleus usually has 23 chromosomes, contains half of the genetic information needed to make a baby Jelly coat protects the eeg and gives sperm nutrients when it passes through Cortical Granules  hardens after a sperm has passed through to stop more sperm cells from entering the egg Sperm cells: Key words; tail, mid-piece, nucleus, acrosome Tail for swimming Mid-piece has lots of mitochondria to power the sperm Nucleus contains half the genetic information for reproduction Acrosome helps the sperm fertilise an egg Factors affecting pregnancy: Alcohol Can cause birth defects and result in fetal alcohol spectrum disorders (FASDs). This can occur in a person who was exposed to alcohol during pregnancy, and effects can include physical problems and problems with behavior and learning. Smoking Can increase the risk of miscarriage and preterm birth; and babies could be born with a low birth weight or certain birth defects. Could also be linked to sudden infant death syndrome (SIDS). Drugs Can cause miscarriage, preterm birth, and birth defects. The baby could also go through drug withdrawal shortly after birth, called neonatal abstinence syndrome, which is very painful. Anything a mother consumes, the baby also consumes. The sex of a baby: Making gametes: The sex of a baby is determined: We can use a Punnet square to determine the PHENOTYPE and GENOTYPE of a baby. The PHENOTYPE is the physical characteristics that we see The GENOTYPE is the genes that are found in the nucleus. Diploids → a cell or organism that contains two complete sets of chromosomes, with one set coming from each parent Haploids → a cell or organism that contains only one set of chromosomes Dominant and recessive: Genotype → the genetic makeup of an organism in terms of alleles (a different version of a gene) Phenotype → the observable features of an organism. Dominant alleles (expressed in capital letters)→ allele is expressed if present Recessive alleles (expressed in lowercase letters) → allele is only expressed when no dominant allele of a gene is present.