Living Environment Grade 9 Regents Study Material

Living Environment Grade 9 Regents Study Material

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Topic 1: Cells

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Homeostasis

is the ability of an organism to maintain an internal balanced environment.

Failure to maintain homeostasis

Can result in sickness or death.

Metabolism

The sum of all the chemical reactions that occur within the cells of an organism.

Organic molecules

Contain skeleton structures with both carbon with hydrogen and oxygen.

Organic Molecule

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Carbohydrates (starch)

Basic Unit - (Lego Blocks):

Glucose (Simple Sugars)

Foods found:

Grains, vegetables, fruit

Proteins

Basic Unit - (Lego Blocks):

Amino Acid (20 kinds)

Foods found:

Meat, egg whites, beans

Lipids

Basic Unit - (Lego Blocks):

Fatty Acid & Glycerin

Foods found:

Animal fats, nuts, oils

Nucleic Acid

Basic Unit - (Lego Blocks):

Nucleotide

Foods found:

Small amounts in all foods

Organization of living things:

(smallest) cells->tissues->organs->organ systems-> organism (biggest)

Organelles

The small parts that make up a cell (each has at least one specific function)

A. Vacuoles

Stores waste and water (large in plant cells, small in animal cells)

B. Ribosome

(very small and is often represented by a dot) located on the ER or in cytoplasm. Ribosomes are where proteins are made (protein synthesis).

C. Mitochondria

(The Powerhouse of the cell where energy is made) the Site of cellular respiration is in plant and animal cells.

Formula for cellular respiration:

Glucose + oxygen -> carbon dioxide + water + ENERGY (ATP)

D. Chloroplasts

Only in plant cells: where the process of photosynthesis occurs.

Formula for photosynthesis

Sun's energy + carbon dioxide + water -> glucose + water + oxygen

E. nucleus

is the control center of the cell and contains DNA (the program or code of life)

F. cytoplasm

Is the liquid media that fills the cell.

6.cell membrane:

1.separates the contents of the cell from the outside environment

2.controls the transport of materials into and out of the cell (selective permeability)

3. Cellular communication: Recognize and responds to chemical signals by using receptor molecules.

7.Passive transport or diffusion

is the movement of molecules from areas of high concentration to areas of low concentration. (NO ENERGY USED)

8. Active Transport

moving a molecule from LOW concentration to a HIGH concentration (USES ENERGY in the form of ATP)

9. Human Body Systems

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Digestive

breaks down the food into nutrients and puts them into the blood stream.

Organs involved

mouth, esophagus, stomach, small intestine, large intestine, rectum

Organelles with the same function

Vacuole and Lysosome

Circulatory

Carries gasses and nutrients throughout the body

organs involved

heart, arteries, veins, capillaries

Organelles with the same function

Cytoplasm, ER or Golgi

Respiratory

exchanges carbon dioxide and oxygen

organs involved

lungs, alveoli, diaphragm

Organelles with the same function

Cell Membrane

Excretory

removes waste from the blood and then from the body.

Organs involved

kidneys, bladder, urethra

Organelles with the same function

cell membrane or vacuole

Nervous

FAST control the functioning of all body systems

organs involved

brain, spinal cord, nerve cells

Organelles with the same function

nucleus

Endocrine

SLOW control the functioning of all body systems

organs involved

Pituitary, thyroid, adrenal, pancreas, gonads

Organelles with the same function

Nucleus

Topic 2: Life Functions

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10. Control

Chemicals produced in the endocrine glands (HORMONES) and chemicals produced by nerve cells are primarily responsible for communication between cells.

Receptor sites

shapes that fit with the others.

Respiration

the process used by ALL organisms to produce energy by using oxygen to burn sugar in order to release energy in the form of (ATP).

Organelle used in this process:

Mitochondria

11. Digestion-

breaking large molecules down into smaller molecules.

1. Proteins

are broken down into Amino Acids.

2. Carbohydrates and Starches

are broken down into Simple Sugars.

3. Fats (Lipids)

are broken down to Fatty Acids & Glycerol

12. Transport -

-involves the movement of materials inside the cell as well as the movement between parts of a multicellular organism.

13. Excretion -

the removal of all waste produced by the cells of the body.

14. Synthesis

is the making or building of large molecules from smaller ones.

15. Photosynthesis

is the process of storing the energy from the sun in the chemical bonds of glucose (sugar)

Organelle used in this process:

Chloroplast

Formula for Photosynthesis:

Sun + Carbon Dioxide + Water --------enzymes----> Glucose + Oxygen + Water

Where is photosynthesis carried out?

Chloroplasts of Producers (plants)

16. Cellular Respiration occurs

in the Mitochondria of All Organisms both plants and animals.

Formula for Cellular Respiration:

Glucose + Oxygen ----enzymes-----> Carbon Dioxide + Water + Energy (ATP)

17. Enzymes

-special proteins that affect the rate of chemical reactions.

Enzymes are

catalysts used in digestion and synthesis.

Enzyme reaction rates are affected by:

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1. Shape-

"Lock and Key Model" if it is the wrong shape it will not work.

2. Temperature-

each enzyme works best at a specific temperature.

3. Ph-

- each enzyme works best at a specific ph.

18. Dynamic Equilibrium is

a steady state-balance- : HOMEOSTASIS

19. Negative Feedback -

controls hormone levels to maintain homeostasis.

Analogy = Thermostat;

as the temperature in your house goes up, the thermostat turns your heat off; as the temperature goes down, the thermostat turns on. This maintains a balance or a comfortable home.

pancreas

secretes INSULIN

A good example is how our body regulates the amount of sugar in our blood:

When glucose (sugar) levels are above normal the pancreas secretes INSULIN. This hormone prompts glucose to move from the blood into body cells, resulting in a lower glucose level in the blood. Another hormone secreted by the pancreas (glucagon) works in the opposite way. When the glucose level in the blood is too low, this hormone prompts the release of glucose stored in the liver which raises BLOOD SUGAR LEVEL.

20. Our Skin and Circulation Systems are

the body's primary defense against disease-causing pathogens. (Immunity) via White blood cells

21. Surface Receptor Protein-

a molecule found on the cell membrane that the immune system recognizes as either part of the body or an outside invader.

Antigens are

the receptor proteins on the membrane of pathogens (germs).

22. Antibodies are

special proteins produced by the white blood cells that can be thought of as your body's army to fight diseases.

1. Antibodies have specific shapes that fit over specific antigens

2. When an antibody fits into the antigen (receptor on the pathogen) it blocks communication preventing the germ from reproducing and making you sick.

23. Immunity is

our body's ability to fight disease.

Once you have been exposed to a specific virus, white blood cells remember the antigens and produce antibodies that

prevent you from getting sick from the same virus for the second time.

24. Vaccination is

composed of a weakened or dead virus that triggers our white blood cells to produce antibodies to fight a specific pathogen.

25. Diseases are

caused pathogens (virus, bacterium, and fungus)

TOPIC 3: REPRODUCTION

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26. Cell Division

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Two types:

mitosis and meiosis

Mitotic division

-Asexual reproduction

-ONE cell division 1 ->2

-Parent cell divides equally to produce 2 identical daughter cells

-Genetic makeup identical to parent 2n - Diploid #

-Function: To produce Identical cells used for growth and repair.

Meiotic division

-Sexual reproduction

-TWO cell divisions 1 -> 4

-Parent cell divides twice to produce either 4 sperm cells or (female) 3 polar bodies + 1 Egg (ovum)

-Genetic makeup 1/2 of the parent cell 1n - Haploid #

-Function: To produce sex cells with 1⁄2 of the species chromosome number.

Mitosis is

used for growth, repair and asexual reproduction.

Meiosis

occurs only in the male and female gonads and solely produces gametes.

27. Gonads

are the sex glands. (Ovaries and Testis)

28. Gametes

are sex cells that unite in fertilization to form a ZYGOTE.

29. Zygote

is a fertilized egg.

30. Fertilization

is when a male and female gamete unit.

If the gametes each have 23 chromosomes, then what does their zygote have?

46

31. Differentiation

is the process that transforms developing cells into specialized cells with different structures and functions.

Tissues

are specialized groups of cells.

32. Human female reproductive system:

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1. Vagina

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2. Uterus

is where the baby develops

3 Ovaries

are the female gonads that produce the egg and important female hormones.

The Placenta

-is the organ that is attached to the baby via the umbilical chord and provides nutrients, oxygen to the fetus and removes waste through the process of diffusion.

-Mother and baby's blood does not mix!