Human Sensory Organs and Effectors: Functions and Structures

The Eye

The eye receives light where the photoreceptors are located. Photoreceptors in the eye transform stimuli into electrical impulses and transmit the information to the optic nerve.

  • Lens: transparent and elastic organ
  • Retina: innermost layer, two types of photoreceptor cells (rods and cones)
  • Choroid: second layer, the iris appears colored. In the center of the iris there is an orifice called pupil.
  • Sclera: outermost layer, frontal part (transparent, forming the cornea)
  • Fovea: best visibility
  • Blind
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Pharmaceutical Processes and Techniques

Construction

The body of a double cone mixer consists of two cone-shaped sections joined to a central section. The rotational axis is perpendicular to the cone axis and passes through the central section. The blender body is held by two lateral supports, one of which is fitted with the driving motor.

Working

The double cone blender is attached to the two lateral supports to prevent movement of the mixture. The materials are then loaded, and the lid of the blender is closed. The equipment is then switched

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Understanding Immunity and Immune System Functions

a) Immunity is the state of resistance or protection of the organism to an infection caused by a particular antigen. The immune system is a complex network of cells and proteins that defends the body against infection. When talking about the organisms that take part in this system there are many.

Regarding the organs, they are divided into primary lymphoid organs and secondary lymphoid organs. Those included in primary lymphoid organs are the bone marrow and thymus. Indeed, cells of the immune system

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Homeostasis, Response, and Regulation in Living Organisms

Homeostasis

Homeostasis is the maintenance of a constant internal environment to ensure optimum conditions for enzyme and cellular function. It controls body temperature, blood sugar concentration, water levels, etc. Nervous and hormonal communication is involved in the automatic control system. All control systems have receptors (cells that detect stimuli), coordination centers (to process information), and effectors (the thing that brings about the response – muscle or gland).

Human Nervous System

Normal

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Understanding Human Circulation and Excretory Systems

Arteries

They take the blood from the heart and carry it towards other organs. They have thick elastic walls with smooth muscle tissue, to resist the high pressure of the heart pumping and control its diameter and capacity. As they branch into thinner vessels, they’re called arterioles.

Blood Plasma

Water with minerals, proteins, and a lot of other dissolved substances (nutrients, wastes, hormones…). About 55% of blood.

  • Erythrocytes (red blood cells): shaped as biconcave disks without a nucleus, they
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Plant Reproduction and Growth: Phloem, Xylem, and Tropisms

Phloem

The phloem moves food substances that the plant has produced by photosynthesis to where they are needed for processes such as:

  • Growing parts of the plant for immediate use
  • Storage organs such as bulbs and tubers
  • Developing seeds

Asexual reproduction generates offspring that are genetically identical to a single parent.

Step 1: After pollen has landed on the stigma, it goes a pollen tube down through the style to the ovary.
Step 2: The nucleus of the pollen grain travels down the pollen tube and

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