ملخص وأوراق عمل أحياء صف تاسع متقدم فصل أول
ملخص وأوراق عمل أحياء صف تاسع متقدم فصل أول
مرفق لكم ملخص وأوراق عمل أحياء صف تاسع متقدم فصل أول مناهج الامارات
معلومات المذكرة
- نوع الملف: ملف تلخيص
- المادة: أحياء
- الصف: التاسع متقدم
- الفصل الدراسي: الفصل الأول
- صيغة الملف: pdf متاح للتحميل
[highlight color=”blue”]صندوق تحميل الملف[/highlight]
Cellular Transport
the movement across the plasma membrane occurs through 2 basic processes: passive transport and active transport
Active transport is the movement of materials across the plasma membrane from an area of lower concentration to an area of higher concentration, with the use of energy from the cell
carrier-assisted transport (pumps)
carrier proteins embedded in the plasma membrane move ions
Example: The sodium-potassium ATPase pump
(Na+/K+ ATPase pump)
Transports 3 Na+ out of the cell and 2 K+ into the cell
vesicle-mediated transport
vesicles that fuse through the cell membrane moves large materials
Example: endocytosis and exocytosis
a vesicle is a small sac
enclose large materials and can pull
materials into or out of the cell
Endocytosis
a type of active transport that moves particles into a cell
Exocytosis
type of active transport that moves particles outside a cell
The difference in concentration of molecules across a space is called the concentration gradient
Active transport is the movement of materials against a concentration gradient and that i
requires the use of energy from the cell
ATP (adenosine triphosphate)
- adenine
- sugar
- 3 phosphate groups
Passive Transport is the movement of materials through the plasma membrane from an area of higher concentration to an area of lower concentration, that does not require energy from the cell
simple diffusion
movement of small or nonpolar molecules such as oxygen and carbon dioxide across the plasma membrane
osmosis
movement of water molecules across the plasma membra
Facilitated diffusion
movement of large or charged molecules, such as proteins and ions, through water-filled transport proteins
Based on the solute concentration, solutions can be categorized as isotonic, hypotonic, and hypertonic solutions
- Isotonic solution the concentration of solute is the same inside and outside the cell
- Hypotonic solution the concentration of the solute outside the cell is lower than it is inside
- Hypertonic solution the concentration of the solute outside the cell is higher than it is inside
Channel proteins
are like pores that open and close and allow ions to diffuse across the plasma membrane
Carrier proteins
carry large molecules, such as glucose, across the plasma membrane by changing shape after they bind to the molecule
At dynamic equilibrium,
the concentration of molecules is the same throughout the space. The movement of particles between the two sides still occurs, but the rate of movement is the same
Main factors that affect the rate of diffusion
A higher concentration can increase the number of collisions between the particles, and this increases the diffusion rate
A higher pressure can increase the collision between the particles, and this increases the diffusion rate
A higher temperature can increase the speed of collisions between the particles and this increases the diffusion rat
The Digestive Organs
Esophagus
a hollow muscular tube that connects the pharynx to the stomach
has smooth muscles that lines its walls
cm long 25
move the food from mouth to the stomach by peristalsis
Stomach
a hollow, muscular sac that connects the esophagus to the small intestine
has three overlapping layers of smooth muscles that line its walls
has capacity of 50 mL when empty and expands to 2 to 4 L when full
Small Intestine
a long tube that connects the stomach to the large intestine
the longest part of the digestive tract, about 7 meters long
has a diameter of 2.5 cm
has smooth muscles that lines its walls
Large Intestine
the final section of the digestive tract
about 1.5 meters long
has a diameter of 6.5 cm
includes the colon, the rectum, and the appendix
1- you swallow
2- the epiglottis covers your trachea
3- the food or drink goes down the esophagus
4- the cardiac sphincter closes after food enters your stomach
5- muscles in the stomach churn food and form chime
6- chime leaves your stomach through the pyloric sphincter
7- much of the chemical digestion takes place in the first part of your small infesting
8- the absorption of nutrients occurs villi in the small intestine
9- the large intestine absorbs water from the undigested food
10- solid waste exit the body through the anus
The Endocrine System
is composed of glands that produce and secrete hormones and functions as a communication system for the body
? What are endocrine glands
Endocrine glands are glands that release their hormones directly into the bloodstream
? What are hormones
Hormones are chemical messengers that travel in the bloodstream and act on target cells
Types of Hormones
Steroid Hormones
composed of lipids – cholesterol •
can easily pass through the plasma membrane because they are soluble in lipids •
bind to receptors inside the cell •
examples of steroid hormones include: estrogen and progesterone •
Amino Acid Hormones
composed of amino acids •
cannot easily pass through the plasma membrane because they are not soluble in lipids •
bind to receptors on the surface of the cell •
examples of amino acid hormones include: insulin and growth hormone •
Amino acid hormones initiate biochemical
pathway causing the cell to produce
the desired response
Steroid hormones act by
entering the nucleus and
activate specific genes
The Endocrine System & Homeostasis
Homeostasis in the body is maintained by internal feedback mechanisms called negative feedback
Negative feedback returns the system
to a set point once it deviates from it
Insulin and glucagon have opposite actions. They maintain the level of glucose in blood by a negative feedback loop
Thyroid and parathyroid hormones have opposite actions. They maintain the level of calcium in blood by a negative feedback loop
Diabetes
Type 1 Diabetes
little or no insulin is produced by the pancreas
appears by the age of 20
Type 2 Diabetes
the cells of the body do not respond to insulin
occurs after the age of 40
